Practitioner Issue 2

Published by the Florida Association of Equine Practitioners, an Equine-Exclusive Division of the FVMA

Issue 2

•

2020

ANATOMY AND IMAGING OF THE EQUINE FOOT AND DIGIT W. RICH REDDING DVM, MS, DACVS

FORE AND HIND PROXIMAL SUSPENSORY INJURY KURT SELBERG MS, DVM, DACVR

SUCCESS AND FAILURE IN THE ADVANCEMENT OF EQUINE REHABILITATION PROTOCOLS TRACY A. TURNER

DVM, MS, DACVS, DACVSMR

IMPROVING PRACTICE PROFITABILITY AMY L. GRICE

VMD, MBA

EXECUTIVE COUNCIL

The President's Line Hello fellow practitioners,

RUTH-ANNE RICHTER

BSc (Hon), DVM, MS FAEP COUNCIL PAST PRESIDENT

rrichter@surgi-carecenter.com

ADAM CAYOT DVM

adamcayot@hotmail.com

AMANDA M. HOUSE DVM, DACVIM

housea@ufl.edu

COREY MILLER DVM, MS, DACT

cmiller@emcocala.com

ANNE L. MORETTA VMD, MS, CVSMT, CVA

maroche1@aol.com

I hope that this COVID-19 pandemic has had minimal adverse effect on your families, friends, and businesses. Our association did a phenomenal job getting our profession classified as an essential business so that, if we felt comfortable doing so, we could continue to practice. Events like this demonstrate the value of membership and the importance of supporting our professional organizations. I feel fortunate to be an equine practitioner. Interacting with horses, colleagues, and owners has kept me in a good place mentally throughout this ordeal — I hope it has done the same for you.

With the summer, there is hope that we can return to a lifestyle resembling normalcy.

We can take advantage of the weather and enjoy outdoor activities with our families and friends, while following the recommendations and mandates intended to keep us safe and stop the spread of the coronavirus. We hope we will be able to resume all of our normal equestrian activities soon.

This issue of The Practitioner has some excellent, pertinent articles in it. In every issue, we strive to include papers with practical tips that we can implement right away in our practices. It’s the dissemination of articles like these that keeps our knowledge fresh and our practices on the cutting edge.

In the veterinary field, we are constantly striving for excellence — and we look forward to normalcy — so we can once more come together to learn and network.

Our Ocala Equine Conference is scheduled to proceed as planned in January with some modifications for personal safety added. It is an exceptional program with quality speakers presenting the newest information. As always, it is being held at a great venue that will allow you to both relax and network with other veterinarians.

JACQUELINE S. SHELLOW

Thank you for your strength and dedication and the resolve that you have shown in these difficult times. We appreciate you, our FAEP members; our educational partners who give us incredible support; and the FAEP/FVMA staff for all their help.

Thank you everyone. We will continue to learn, grow, and excel together.

jackie@shellow.com

Best wishes,

DVM, MS REPRESENTATIVE TO FVMA EXECUTIVE BOARD

Armon Blair, DVM FAEP Council President PHILIP J. HINKLE EXECUTIVE DIRECTOR

phinkle@fvma.org

If anyone is feeling too stressed or mentally unwell, please do not hesitate to reach out to colleagues, friends, or the FAEP (call 800.992.3862).

Opinions and statements expressed in The Practitioner reflect the views of the contributors and do not represent the official policy of the Florida Association of Equine Practitioners or the Florida Veterinary Medical Association, unless so stated.

Placement of an advertisement does not represent the FAEP’s or FVMA’s endorsement of the product or service.

FAEP | 7207 MONETARY DRIVE, ORLANDO, FL 32809 | PH: 800.992.3862 | FAX: 407.240.3710 | EMAIL: INFO@FVMA.ORG | WEBSITE: WWW.FAEP.NET

2 The Practitioner

Issue 2 • 2020

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6/8/20 9:48 AM

ANATOMY AND IMAGING

of the Equine Foot and Digit W. RICH REDDING | DVM, MS, DACVS

Some of this content was presented at a previous AAEP focus meeting and is reprinted with permission.

The vast majority of lamenesses that occur in the horse originate in the foot. Clinical examination is an essential part of any lameness examination and frequently directs the clinician to an area that is suspected as the source of pain. However, diagnostic analgesia is necessary to isolate the source(s) of pain and to more accurately direct diagnostic imaging. Interpretation of diagnostic analgesia of the foot can be difficult due to the significant overlap of these blocks. Inaccuracies in analgesia techniques can also occur due to diffusion of the local anesthetic proximally along the nerve or out of the distal interphalangeal joint/navicular bursa. Diagnostic imaging becomes even more important to further define the cause of the lameness originating in the foot.

Anatomy of the Foot The Hoof

The hoof is a highly keratinized stratified squamous epithelium.

The external surface of the hoof wall has fine parallel lines that extend from the coronary border to the solar border. These lines are the horn tubules, which grow distad from their origin from the basal layer of cells (stratum germinativum) of the coronary epidermis, which cover the papillae of the coronary corium.

There are also raised transverse ridges in the hoof wall parallel to the coronary band (perpendicular to the horn tubules), which is an indication of the variable growth activity of the hoof wall (influenced by environmental and internal factors). The external surface of the hoof wall is divided into three topographical regions: the dorsal region at the toe, which blends medially and laterally into the quarters, which blends into the rounded heels.

The hoof wall is thickest at the toe and thins through the quarters to the heels. The wall reflects upon itself at the heels to form the bars, which are continuous with the sole and are separated from the frog by the paracuneal grooves. The frog is made up of a central groove and two crura. The frog is expanded palmarly and covered by periople to form the bulbs of the heel. The tubular horn and intertubular horn of the frog epidermis is less highly keratinized and has a higher moisture content (50%). Merocrine glands secrete onto the surface of the frog.

Imaging techniques available to the equine practitioner include radiography, ultrasonography, thermography, nuclear scintigraphy, computed tomography, and magnetic resonance imaging. To best utilize all of these imaging modalities, the clinician should develop a good working knowledge of the anatomy of the foot.

The clinician must also have an appreciation of the advantages, disadvantages, and limitations of each imaging modality as well as the appearance of the anatomy and pathophysiology characteristic to each technique. With many of these imaging modalities, it is necessary to appreciate the anatomical appearance of many of these structures in cross section, sagittal section, and frontal section.

With each imaging modality, normal anatomical variations exist, and it is important that the clinician recognize these variations as The internal surface of the hoof wall is excavated proximally by normal to prevent an inaccurate diagnosis. The opposite limb can the coronary groove. The groove is perforated by innumerable and should be used for comparison, while recognizing that disease small openings, which receive the papillae of the coronary corium. can occur at the same location in the opposite foot. Successful Below the coronary groove, the wall bears about 600 epidermal management of foot lameness requires the clinician to incorporate lamellae each with approximately 100 secondary lamellae. These all the information at their disposal, from the clinical examination epidermal lamellae interdigitate with the dermal lamellae of the to the imaging results, in order to develop an accurate diagnosis laminar corium. The laminar corium blends with the subcutis and these further blend into the periosteum of the parietal surface of and to choose the most appropriate treatment. the distal phalanx. Histologically, the hoof wall is divided into the This paper is divided into a discussion of the detailed, normal stratum externum, stratum medium, and stratum internum. The anatomy of the foot1,2 and the imaging techniques frequently stratum medium makes up the bulk of the hoof wall. Cells from utilized to assess the foot. The discussion on imaging will highlight the actively proliferating stratum germanitivum of the laminar the advantages and limitations of the various imaging modalities epidermis form the epidermal lamellae of the stratum internum, which moves distad. The junction of the stratum internum with in defining the normal anatomy. the horn of the sole is the white line.

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The hoof wall is nourished by the subjacent corium, which is a collagenous connective tissue with an extensive arterial supply with a capillary network of large diameter capillaries and interconnecting venous sinuses. Blood vessels of the corium cushion the foot upon impact. The corium is the specially modified and highly vascular continuation of the connective tissue layer of the skin. It supplies attachment and nutrition to the hoof wall. The corium is divided into five regions: perioplic, coronary, laminar, solar, and frog.

The germinal layers of the epidermis cover the corium and produce the horny components of the hoof.

Distal Interphalangeal Joint & Navicular Apparatus

Figure 1. The bones of the digit including the proximal phalanx, middle phalanx, distal phalanx, and the navicular bone looking dorsal to palmar.

Photo courtesy of Dr. W. Rich Redding.

Figure 2. The bones of the digit including the proximal phalanx, middle phalanx, distal phalanx, and the navicular bone looking lateral to medial.

Photo courtesy of Dr. W. Rich Redding.

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The bones of the distal limb that make up the digit include the distal phalanx (P3), the middle phalanx (P2), the proximal phalanx (P1), and the navicular bone. The distal interphalangeal (DIP) joint is a complex joint positioned at the distal aspect of the digit encased in a horny hoof capsule (Figures 1 and 2). The DIP articulation includes the middle phalanx, the distal phalanx, and the navicular bone. The proximal interphalangeal (PIP) articulation is made up of the middle phalanx (P2) and the proximal phalanx (P1).

The boney column of the DIP joint exists primarily within the dorsal half of the foot while the energy dissipating soft tissue structures (frog, digital cushion, cartilages of the distal phalanx, and the associated venous sinusoids) of the foot reside in the palmar half. The distal phalanx is a uniquely shaped pyramidal bone with three surfaces: the articular, the parietal, and the solar surfaces. The proximal aspect of the distal phalanx has two large concave glenoid cavities that articulate with the condyles of the head of the middle phalanx. The middle phalanx has a palmar flattened area that articulates with two shallow depressions on the dorsoproximal aspect navicular bone (NB). The NB also articulates on its distal border by means of a transverse facet with the distal phalanx. The dorsal aspect of the joint is bounded (crossed) by the common digital extensor tendon (CDET) or long digital extensor tendon (LDET) in the hind limb as it courses to its attachment on the extensor process of P3. The fibrous joint capsule blends with the digital extensor tendon and the collateral ligaments of the DIP joint. The relatively short medial and lateral collateral ligaments (CL) of the DIP joint originate more dorsally from the distal aspect of P2 and incline somewhat palmar/plantar to insert on depressions on either side of the extensor process of the distal phalanx. The CLs widen as they course distally and are partially covered by and attached to the collateral cartilages of the foot. These ligaments are oriented vertically (perpendicular to the ground surface) rather than parallel to the axis of the limb. They support the DIP joint during movement, primarily in the sagittal plane but also in the frontal and transverse planes. More proximally on the digit, the collateral suspensory ligaments (CSLs) attach to the depressions on the distal end of the extremities of distal P1 and extend to the proximal margin of the NB.

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is far more extensive than the dorsal pouch and is made up of a proximal and distal pouch.

Deep Digital Flexor Tendon

Figure 3. The navicular suspensory apparatus includes the medial and lateral collateral suspensory ligaments (CSL) of the navicular bone and the distal sesamoid impar ligament (DSIL).

Photo courtesy of Dr. W. Rich Redding.

The caudal aspect of the joint is more complex because of the navicular suspensory apparatus. The navicular apparatus includes the navicular bone (NB), the collateral suspensory ligaments of the navicular bone (CSL), the distal sesamoidean impar ligament (DSIL), the navicular bursa, the deep digital flexor tendon (DDFT), and the distal digital anular ligament. The distal navicular bone is shuttle shaped and has two borders, two surfaces (flexor and articular), and two extremities. The navicular suspensory apparatus forms a strong, somewhat elastic sling that supports the NB to the back of the DIP joint and is thought to function to maintain a constant angle of insertion and the mechanical advantage of the DDFT onto P3. The CSLs arise from the distal surface of P1 (see above) pass in a distopalmar direction, attaching to P2 to insert on the extremities of the NB. The DSIL extends from the distal margin of the NB to the flexor surface of the termination of the DDFT (Figure 3). The DDFT flattens and expands medial to lateral over the flexor surface of the NB coursing to its insertion with the DSIL onto the entire flexor surface of P3. These parallel fibers of dense connective tissue are separated by loose connective tissue, within which are many sensory nerves and numerous blood vessels.

The DIP joint has a large dorsal pouch, which blends with the common digital extensor tendon (CDET) dorsally and the CLs abaxially. The DIP joint also has a palmar pouch, which is more extensive and is subdivided into a proximal palmar and a small distal palmar pouch. The proximal palmar pouch can extend dorsally around the palmar aspect of the collateral ligaments. Of clinical significance, the lateral limits of the proximal pouch extend to the abaxial surfaces of the cartilages of the P3. The palmar pouch

6 The Practitioner

The DDFT courses distally in the pastern after coursing through the fetlock canal. The DDF and SDF are surrounded by the digital flexor tendon sheath (DFTS) proximal to the fetlock and the DDF is surrounded by the DFTS as it courses through the pastern to the distal aspects of the digit (Figure 4). The DDFT courses through the fetlock canal as an oval structure that begins to expand in a medial to lateral direction. The DDFT becomes bilobed as it progresses distally. The DDF is surrounded by the two rings of the SDFT called the macula flexoria (MF). The proximal ring is more robust and exists proximal to the fetlock canal while the distal ring is thinner and exists in the mid pastern. The fibers of both rings of the MF are continuous with the SDF tendon. At the mid-pastern area, just distal to the distal ring of the MF, there is a vinculum that attaches to the dorsal aspect of the DDF in the central depression between the two lobes. The DDF tendon continues to widen medial to lateral as it courses more distally before passing over the NB. There is a proximal digital anular ligament (PDAL) and a distal digital anular ligament (DDAL) that holds the DDF tendon centrally in its course through the pastern (Figure 5).

The DFTS extends further distally on the dorsal surface of the DDFT than on the palmar surface. The dorsal aspect of the DFTS comes in close contact with the navicular bursa and DIP joint and is separated from these by the so called “T” ligament. The T-ligament is a fibrous connection between the DDFT and the middle of the palmar surface of P2. The navicular bursa lies

Figure 4. Superficial flexor and deep digital flexor tendon are surrounded by the digital flexor tendon sheath in the digit. The superficial flexor tendon branches just proximal to the pastern joint and inserts on distopalmar P1 and proximopalmar P2. The deep digital flexor tendon courses to its attachment on P3.

Image provided by Dr. Andy Parks and copyrighted by The Glass Horse.

Issue 2 • 2020

of adipose tissue and small amounts of fibrocartilage. A venous plexus is interposed between the proximal aspect of the cartilages and the digital cushion. The digital cushion extends from the DDFT to the cuneate corium. The digital cushion extends palmarly and forms the base of each of the heel bulbs.

Advantages and Limitations of Imaging the Foot Clinical Examination

Figure 5. The SDF & DDF tendons are surrounded by the primary anular ligament at fetlock and the proximal digital anular ligament and distal digital ligament in the pastern.

Image provided by Dr. Andy Parks and copyrighted by The Glass Horse.

between the DDFT and the flexor surface of the NB. The DDFT continues to course distally, expanding to a fan-like shape before inserting on the facies flexoria and semilunar crest of the P3. The dorsal portion of the DDFT blends with the DSIL immediately before insertion on to the facies flexoria of the P3. The navicular bursa lies between the DDFT and the DSIL initially, until these two structures begin to blend together before inserting on the semilunar crest of P3. The DDFT has a dorsal fibrocartilaginous pad that supports pressure on the transverse prominence of the proximopalmar aspect of P2.

Cartilages of the Distal Phalanx & Digital Cushion

The cartilages of the P3 are fibrocartilaginous structures that lie adjacent to, and are attached to, the dorsal aspect of the CLs and the dorsal aspect of the palmar processes of all feet. The cartilages are attached to adjacent structures by several ligaments including the P1, P2, P3, and the CDET/LDET. The proximal aspect of the collateral cartilages project above the coronary band and are palpable in the palmar/plantar aspect of the foot. The cartilages can have a variable shape and size as well as varying degrees of ossification. When ossification occurs it typically progresses proximad from the attachment of the cartilage. The palmar/ plantar aspect of the cartilages is perforated by veins. A complex relationship exists between the cartilages and the digital cushion. It is thought that their combined role is energy dissipation associated with the concussion of the foot with the ground.

The region between the cartilages of the P3 is occupied by the digital cushion, which is a modification of the subcutis. It is made up of poorly vascularized fibroelastic tissue, which contains depots

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The clinical examination is the most important aspect of any lameness evaluation. A thorough clinical examination will determine the most appropriate course of action for the rest of the lameness workup. Imaging should not be performed until the completion of the clinical examination. The clinical examination should begin with a visual assessment of the horse while the horse stands quietly in its stall and while it stands evenly on firm, level ground. Observations should include the horse’s stance; muscle symmetry; enlargements of joints, tendons, or ligaments; and any conformational defects that might predispose to lameness.

Specific evaluation of the feet should include a thorough visual assessment including foot shape, symmetry, and type of shoeing.

Once the limb is lifted off the ground, the wear patterns of the hooves and/or shoes should be noted and hoof testers applied to each foot in a systemic manner. Lameness suspected to originate in the foot should have provocative tests of the foot (hoof extension stress test, frog pressure test) performed and these can be quite useful in further defining the source of pain. A thorough lameness examination should include observation of the horse at a walk and trot in hand on a hard and soft surface. Distal and proximal limb flexion tests are performed to exaggerate lameness and isolate a painful response associated with a particular joint.

A more complete discussion of the examination of the foot will be presented in another section of this paper as well as the inaccuracies of these flexion tests. At this stage, a presumptive diagnosis is made directing the clinician to perform the most appropriate ancillary diagnostic tool.

Ancillary Diagnostics

The clinician should attempt to confirm the source of pain by utilizing diagnostic anesthesia. There are many inaccuracies that can occur with regional and intra-articular/bursal anesthesia.

Numerous recent studies pertaining to anesthetic techniques of the foot should be reviewed to understand the current concepts of what may or may not be blocked by these different blocks and these will be discussed in another section of these proceedings.3,4 Once the foot has been identified as the cause of lameness and the pain localized, diagnostic imaging techniques should be utilized to assess internal structures of the foot. Imaging techniques that are utilized in the horse include radiography (plain film, computed, and digital), ultrasonography, thermography, scintigraphy, computed tomography, and, more recently, magnetic resonance imaging.

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Every lameness examination associated with the foot should have a radiographic examination. If the radiographic examination does not reveal any significant boney abnormalities, then an ultrasonographic examination should be performed to evaluate the soft tissue structures available to this imaging technique.

When radiographic and ultrasonographic examinations are unable to elaborate a significant abnormality, then nuclear scintigraphy, computed tomography, and magnetic resonance imaging should be considered. The advantages and disadvantages of each modality should be weighed against the risks and expense before proceeding.

Radiography

Radiography of the digit is the most common imaging study performed by the equine clinician. As always, the clinician should utilize the information gained from the clinical and lameness exam to direct the radiographic examination. Good radiographic technique and an understanding of the relationship of limb position, cassette position, and x-ray tube angle is critical.5,6 Inadequate foot preparation, inappropriate projections, and motion (of the animal and/or the examiner) create artifacts that compromise the diagnostic quality of the radiographic study. These correctable technical problems, if not addressed, can cause major errors in interpretation. In addition, good radiographic technique requires detailed knowledge of the anatomy of the foot and an understanding of the pathophysiology of the diseases. There are many sites that might appear to be a manifestation of disease but are simply normal variation in anatomy or occur because of an abnormal oblique projection. For example, nutrient foramen locations can be variable but are characterized by a slight lifting of the endosteum not seen with fractures. Enthesis, which is new bone at sites of attachment of tendon, ligaments, and joint capsules to bone surfaces, can appear similar to reactive new bone.

However, the clinician must recognize that certain sites of enthesis can occur commonly without clinical manifestation of lameness.

This is particularly true at the dorsal aspect of P2 and the extensor process of P3. Other incidental findings associated with the foot include the dorsal notch in the toe of P3 (crena) and various stages of ossification of the collateral cartilages (side bones). Anatomical specimens and textbooks can be quite helpful in understanding the radiographic appearance of a structure that can appear on a radiograph due to a change in the radiographic positioning.

within the hoof capsule, a block is necessary to elevate the foot off the ground and place the central beam at or just above the solar surface of the foot. When looking at the navicular area, the central beam should be directed just below the coronary band midway between the toe and the heels. Special techniques are helpful to detail specific areas and include contrast arthrography of the DIP and/or PIP joints, stress radiographs, navicular bursagrams, digital venograms, and fistulagrams. It may be helpful to place radiopaque markers at specific locations on the hoof wall (most commonly barium paste is coated on the dorsal hoof wall at the toe for a laminitis study) to demonstrate the relationship of the hoof wall and distal phalanx.

Acute injuries may not initially demonstrate a radiographically apparent abnormality. However, it may take a period of 5-7 days before the inflammatory reaction causes resorption or production of enough bone to be evident radiographically. Therefore, it may be necessary to repeat the radiographic study after a sufficient period of time before declaring that a radiographic abnormality doesn’t exist. Distal phalanx fractures are frequently not apparent on initial radiographic study but become apparent on later examinations.

Ultrasonography

Diagnostic ultrasonography is a two-dimensional, real-time imaging technique that utilizes the transfer and propagation of sound waves into soft tissue. Ultrasonography has proven to be very effective at evaluating soft tissue structures of the palmar/plantar metacarpus/metatarsus of the distal limb in the horse.7-9 However, when used in combination with radiography, ultrasonography can supply more information about any number of orthopedic problems than when each modality is used alone. In horses with lameness in the foot, ultrasonography can be quite valuable when the radiographic study is inconclusive and the presumed injury is soft tissue in nature. Ultrasonography can also be particularly useful when the radiographic survey of the foot demonstrates an abnormality but further evaluation of the soft tissues of this area is needed. The structures in the equine foot that can be examined with ultrasonography include the DDFT, CSL of the NB, the DSIL, the DDAL, the navicular bursa, the NB (flexor surface, proximal and distal borders), the palmar/plantar surface of P3, the CLs of the DIP, and the digital cushion. However, the examiner must recognize that the various tissue types and tissue orientation (specifically the tendon and ligament fibers) can significantly affect the transmission and reception of sound. For example, the exterior hoof wall has very low water content and acts as a barrier to sound transmission while the frog has higher water content (than the hoof wall) and can transmit sound. The standard ultrasonographic examinations of the foot will be discussed in another section.

The clinician should perform a standard radiographic examination consisting of a minimal number of projections. A standard radiographic study of the foot should include a dorso 00 palmar (D0Pr), lateromedial, dorso 65o proximal-palmarodistal oblique (D45Pr-PaDiO P3 technique), dorso 65o proximal-palmarodistal oblique (D65Pr-PaDiO coned down navicular technique), palmaro 40-75o proximal-dorsodistal oblique (Pa45Pr-PaDiO navicular skyline), and a dorso 45o proximal-palmarodistal oblique (D45Pr- The accuracy of ultrasonography depends on the skill and PaDiO). These will be discussed in detail in another section of experience of the operator both during image acquisition and these proceedings. Special projections may be necessary to image interpretation. The operator must understand some basic highlight an area to confirm that a structure is indeed abnormal sound-tissue interactions and recognize how this will affect the or to demonstrate a specific anatomical area more completely. As information and misinformation (artifacts) created during the a rule, the central beam should be directed at the area of interest. examination. To be of maximum diagnostic quality, the sound For example, when looking at the position of the distal phalanx beam should be perpendicular to the fiber orientation of the 8 The Practitioner

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tendon or ligament being examined. However, because the course of the deep digital tendon is not perpendicular to the windows normally utilized to image within the foot, it is impossible to obtain the 900 beam angle to the fibers of the deep flexor tendon through the existing windows (frog and bulbs of the heel). A lack of a perpendicular beam angle to the DDFT in the foot creates significant beam angle artifact (hypoechoic artifacts within the DDFT) seen most often on transverse images. This beam angle artifact compromises the accurate interpretation of architectural change. Image acquisition is further complicated by lack of an adequate window for sound transmission. The examination of many of the soft tissue structures within the foot is limited to the proximal aspect of the structure present above the horny hoof capsule or through the frog. Access through the frog can be influenced by environmental conditions, which influence the water content of the frog. Dry conditions may require soaking the foot to increase sound transmission and the quality of the image.

In addition, the horse with chronic lameness associated with the foot will frequently have an atrophied frog, further limiting the window available to evaluate the internal structures of the foot. Furthermore, MR studies of the foot have demonstrated that most of the DDF lesions are more abaxial either in the medial or lateral lobes and probably not apparent during the ultrasonographic examination.

Nuclear Scintigraphy

Nuclear scintigraphy has become routinely utilized in the horse for detection of orthopedic disease.10-12 A radiopharmaceutical is injected into the intravenous system and is distributed throughout the body. Technetium pertechnetate is bound to a pharmaceutical called methylene diphosphonate (MDP).

Methylene diphosphonate binds to osteoblasts that are actively remodeling bone. By doing this, the radioactive technetium is deposited at the site of osteoblastic activity and, as the radioactive material decays, it emits a gamma ray. This gamma radiation escapes the body for external detection and measurement by a scintillation camera. The camera detects the gamma radiation and a dedicated computer creates an image of radiation distribution.

This makes scintigraphy an especially valuable tool to diagnose early orthopedic injury. Musculoskeletal scans are divided into vascular phase, pool phase, and bone phase (first pass, soft tissue, and osseous). An area of increased uptake of radiopharmaceutical can indicate active inflammation in pool phase images and bone modeling in bone phase images. The metabolic rate of bone significantly influences the uptake of the radiopharmaceutical during the osseous phase; this makes younger animals in training ideal candidates for scintigraphy. Older, mature animals that have minimal bone turnover and are not actively training are poor candidates. In the appropriate candidate, nuclear imaging of bone disease is very sensitive to the detection of bone modeling but is less specific at defining the specific site of involvement. To assist with localization of lesion(s), the scans should be acquired in two planes (lateral and dorsopalmar) and should be compared to the opposite foot. The main drawback to nuclear medicine is that the images generated are extremely sensitive to disease, but not very specific. It is difficult to know the clinical importance of the lesions identified or whether these lesions are acute or chronic. Active

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bone remodeling after an incomplete stress fracture can persist for up to two-three years after the injury. Also, perineural and intra-articular anesthesia can cause increased vascularity to the regions injected and provide false positive results for several days after the procedure.

It must be recognized that there are limitations in interpreting the uptake of radiopharmaceutical in the foot of the horse.8 Image interpretation is subjective and bone modeling does not always equate with pathological conditions or pain. Some conditions in the foot, such as navicular disease, occur bilaterally, making it difficult to compare bone modeling between the feet. Regions of interest (ROI) analysis can reduce some of the subjectivity of interpretation of the foot.8 In particular, the two areas of most clinical concern in the foot are the navicular bone and the insertion site of the deep digital flexor tendon on the distal phalanx, which are in close apposition. ROI analysis allows these areas to be compared to the uptake in the toe region.

Scintigraphy examinations must always be combined with radiographic and ultrasonographic evaluation. The indications for nuclear scintigraphy in the horse with foot lameness include: when there is localization of pain to the foot region but no radiographic or ultrasonographic evidence of a problem; an acute onset of lameness thought to be due to a fracture but without radiographic evidence of a fracture; intermittent lameness that cannot be reproduced to perform anesthesia of the digit; lameness in several limbs making local anesthesia interpretation difficult; and finally, in the assessment of the significance of equivocal radiographic abnormalities. Again, increased radionuclide uptake does not always equate to clinical significance, emphasizing that interpretation of nuclear scintigraphic images without reference to the clinical examination and other imaging results can potentially be misleading.

Computed Tomography

In some cases of foot lameness, radiography, ultrasonography, and nuclear scintigraphy may not be helpful in defining the anatomic origin of the lameness. In addition, some changes seen with these imaging modalities may need more definition. At this point, the clinician has a choice between computed tomography (CT) and magnetic resonance imaging (MRI). Computed tomography can detect more subtle density differences than radiography, making it a much more sensitive tool to evaluate boney disease. Cross-sectional imaging allows visualization of the bones of the foot in much more detail than with conventional radiography.13 CT uses a rotating X-ray beam to penetrate body tissues and generates multiple slice tomographs, which can be utilized to develop a three-dimensional rendering of the area of interest. Newer 8-16 multi-slice CTs are able to acquire the study in minutes, allowing the clinician to read the study, develop a strategy for repair of a fracture, and perform surgery within the same anesthetic period. Multi-planar reformatting can yield better anatomic orientation of an area and provide for more sensitive detection and characterization of disease extension. CT is more sensitive to detecting changes of bone contour and has proven to be particularly useful in the evaluation of stress-induced bone

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Figure 6. Cross-sectional anatomy specimen at the level just proximal to the navicular bone. The DDF and the suspensory ligament of the navicular (CSL) are seen just palmar to the middle phalanx and the proximal aspect of the collateral ligaments of the DIP joint.

Photo courtesy of Dr. W. Rich Redding.

Figure 7. MRI image at the same location as Figure 6 representing a cross-sectional anatomy specimen at the level just proximal to the navicular bone. The DDF and the suspensory ligament of the navicular (CSL) are seen just palmar to the middle phalanx and the proximal aspect of the collateral ligaments of the DIP joint. This is a proton density sequence from a 1.5 tesla Siemens Symphony MR system.

Photo courtesy of Dr. W. Rich Redding.

remodeling, focal bone lesions, and defining fracture configuration prior to fracture repair. However, CT requires general anesthesia to acquire the images or sequences. The foot is ideal for CT evaluation because of the complex anatomic arrangement with the superimposition of the distal and middle phalanx and the navicular bone significantly compromises image interpretation. However, the soft tissue detail in CT is deficient when compared to MRI. The use of intravascular contrast agents can enhance the soft tissue detail but is not comparable to the soft tissue detail obtained with MRI.

remodeling will change the proton content and density, and, thus, the MRI characteristics of that particular tissue. Therefore, MR can demonstrate structural and physiologic alterations within the tissues early in the course of disease, before they are detectable by most other imaging modalities.

MRI has proven to be the gold standard for the diagnosis of musculoskeletal injuries in human medicine and now in the horse.

It provides superior anatomical detail and contrast resolution.

The images are displayed as a cross-sectional tomographic slice of Magnetic Resonance Imaging the area of interest (Figures 6 and 7). The slice thickness may be Magnetic resonance imaging (MRI) is the most recent imaging tool as thin as 1.5 mm and can be acquired in any plane. Knowledge of available to evaluate occult lamenesses originating from the distal normal anatomy and ‘normal’ variations is mandatory. The paired limb of the horse.14-17 MRI images are produced by reconstruction limb should be imaged to allow comparisons of the anatomical of a data set that is produced by an MR scanner. The MR scanner appearance of all structures. Like all other imaging techniques, consists of a powerful magnet (.3 to 1.5 tesla) that generates a static it is necessary to confirm the presence of a lesion seen in one magnetic field. Essentially, MRIs image protons in hydrogen atoms, plane by visualization of that lesion in the orthogonal plane. The which are present in all animal tissue. Protons in hydrogen line objective of MRI is to generate contrast between pathological and up when placed in the magnetic field. Multiple radiofrequency normal tissue. Generally, pathologic tissues have more hydration (RF) coils, placed around the area of interest, send and receive RF than normal tissue and this results in an increase in signal on T2 pulses. The brief RF pulse alters the orientation of hydrogen atoms weighted images and a decreased signal (often hard to detect) on within the magnetic field. As the protons relax or precess, they emit T1 weighted images. It is easier to see bright pathology against measurable energy that is measured by the scanner. In short, MR a dark background of normal tissue. MRI has generally high produces a grey-scale image of hydrogen protons in tissues. The sensitivity and high negative predictive value, but its specificity number and density of these protons in the different tissue types varies depending on the condition and the weighting of the particular MR sequence will produce a MR signal of different intensity. The protons in hydrogen exist in There are several major disadvantages of using MR in equine many different microenvironments and concentrations in the body orthopedics. The cost of performing an MR on the horse is quite and MR techniques measure these differences. For example, tissues high. MR should not be used as a screening study but should with low numbers of protons appear dark on all image sequences. be utilized as a problem-solving tool. Careful clinical evaluation In addition, tissue alterations caused by inflammation and tissue with diagnostic anesthesia, radiography, and ultrasonography

10 The Practitioner

Issue 2 • 2020

should be performed prior to MR. Once the area of interest is defined, the horse must be positioned with the area of interest in the isocenter of the magnet. With low field systems, this requires heavy sedation; with high field systems, general anesthetized is required. Based on the inherent problems with anesthesia in the horse, a finite time constraint must be enforced, which will limit the number of sequences performed. There is a steep learning curve necessary to understand the technology used to generate the diagnostic images (especially with high field strength systems) as well as to read the MR studies and apply this information to managing the problems identified.

Conclusion

Lameness associated with structures inside the foot can be difficult to accurately define. A careful, detailed, clinical examination of the foot including timed and sequential nerve and/or joint blocks is often necessary to further isolate the region that is the source of pain. Knowing the region that is the source of pain can help direct the clinician in choosing the most appropriate diagnostic tool. Diagnostic imaging techniques that are available to the clinician include radiology, ultrasonography, nuclear scintigraphy, computed tomography, and magnetic resonance imaging. Determining the specific structure(s) involved, may require that these imaging techniques be utilized alone or in combination. A good working knowledge of normal anatomy and normal variations of anatomy in the foot are critical to achieving an accurate diagnosis. Errors in interpretation can occur with each of these imaging techniques. Errors are often the result of correctable technical problems or due to a lack of knowledge regarding the normal anatomy of this area. Accurately defining the structure(s) involved leads to the employment of the most appropriate treatment strategy and the best chance for a return to soundness.

References:

8. Sage AM, Turner TA. Ultrasonography of the soft tissues of the equine foot. Equine Vet Educ, AE, August 2002, 278-283.

9. Grewal, JS; McClure, SR, et al. Assessment of the ultrasonographic characteristics of the podotrochlear apparatus in clinically normal horses and horses with navicular syndrome. J Am Vet Med Assoc, Vol 225, No. 12, December 15, 2004.

10. Ross MW, Stacy VS. Nuclear medicine. In Diagnosis and management of lameness in the horse, Dyson & Ross.

Saunders, 2003, 198-212.

11. Dyson SJ. Subjective and quantitative scintigraphic assessment of the equine foot and its relationship with foot pain, Equine Vet J; 2002, 34, 2, 164-170.

12. Dyson SJ, Pilsworth RC, Twardock AR, Martinelli MJ. Equine Scintigraphy, Equine Vet J LTD 2003, 77-96.

13. Peterson PR, Bowman KF. Computed tomographic anatomy of the distal extremity of the horse, Vet Radiology, Vol 29, 4, 1988; 147-156.

14. Dyson, S, Murray, R, Schramme, M, Branch, M. (2003) Lameness in 46 horses associated with deep digital flexor tendonitis in the digit: diagnosis confirmed with magnetic resonance imaging. Equine Vet J. 35, 681-690.

15. Schneider RK, Gavin PR, Tucker RL. What MRI is teaching us about navicular disease? In Proceedings Am Assoc Equine Pract, 2003:49;210-221 16. Dyson S, Murray R, Schramme M. Lameness associated with foot pain: results of magnetic resonance imaging in 199 horses (January 2001-December 2003) and response to treatment. Equine Vet J 37:113-121, 2005.

17. Dyson S, Murray R, Schramme M, et al. Collateral desmitis of the distal interphalangeal joint in 18 horses (2001-2002).

Equine Vet J 36:160 -166, 2004.

W. Rich Redding, DVM, MS, DACVS

1. Kainer RA. Clinical Anatomy of the Equine Foot. Vet Clinics of N Amer; Eq Practice- Vol 5, No 1, April 1989, 1-27.

2. Sisson, S. Equine osteology. In: The Anatomy of Domestic Animals. 5th ed., W.B. Saunders Co., Philadelphia. 1975, 273-279.

3. Schumacher J, Schumacher J, Schramme MC, et al.

Diagnostic analgesia of the equine forefoot.: Equine Vet Educ, June: 199-206, 2004.

4. Schumacher J, Steiger R, Schumacher J, et al. Effects of analgesia of the distal interphalangeal joint or palmar digital nerves on lameness caused by solar pain in horses. Vet Surg, 29:54-56, 2000.

5. Park RD. Radiographic examination of the equine foot. Vet Clinics N Amer; Equine practice, Vol 5, 5, 47-66.

6. Dyson S. Radiography and Radiology, In Diagnosis and management of lameness in the horse, Dyson & Ross.

Saunders, 2003, 153-166.

7. Busoni V, Denoix JM. Ultrasonography of the podotrochlear apparatus in the horse using a transcuneal approach: technique and reference images. Vet Rad & Ultrasound, Vol 42, 6, 2001, 534-540.

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Dr. W. Rich Redding is a clinical professor at North Carolina State University-College of Veterinary Medicine. After studying and graduating from the University of Florida in 1983, he developed a deep appreciation for the performance horse. Over his career he has developed a keen interest in lameness, diagnostic imaging, and orthopedic surgery in the performance horse. Initially in private practice, first in Lexington, Kentucky, and then in Middleburg, Virgina, he decided to pursue residency training in surgery at Iowa State University. This was followed by another stint in private practice emphasizing surgery referral practice for five years in the Twin Cities area of the Midwest. He then came to North Carolina State in 1995. Since joining the staff at North Carolina State, he has continued to explore new techniques in musculoskeletal imaging with a special focus on ultrasound and MRI in the sport horse.

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Issue 2 • 2020

FORE AND HIND PROXIMAL SUSPENSORY INJURY KURT SELBERG | MS, DVM, DACVR

Fore and hind limb lameness due to bony and soft tissue pathologic changes in the metatarsus and metacarpus are common and affect many breeds and disciplines.1-3 In sport horses, the proximal aspect of the muscle interosseous medius, also known as the suspensory ligament, is a welldocumented source and an often scrutinized area of the sport horse. Ultrasound and radiography are typically the first diagnostic imaging test performed to confirm clinical suspicion of disease localized to the proximal metacarpus/carpus and metatarsus/ tarsus.

HINDLIMB:

The bulk of the hind suspensory ligament originates on the plantaroproximal aspect of the third metatarsal with proximal fibers originating on the fourth tarsal bone. At its proximal extent, the origin is bilobed and valentine or trapezoid in shape, composed of fat, muscle, and tendinous tissues.4 Despite the frequency of this injury, diagnosis can be challenging as horses can vary in their presenting signs, and the often-bilateral nature of the disease confounds the diagnosis. The overlap with clinical signs associated with lameness, originating primarily from the tarsus, also confounds clinical diagnosis.5,6 Ultrasound and radiography are often used as primary modes of injury diagnosis in fore and hind limb suspensory ligament disease.

Ultrasound approach has progressively changed for the hind and suspensory ligament. Initially, weightbearing plantar approaches were used, then plantaromedial with on and off angle images, a plantaromedial non-weight bearing, and now a more plantar non-weight bearing approach is used in combination with examination form plantaromedial and lateral (Figure 1).7,8 Imaging/pathologic findings associated with the hind suspensory ligament vary. Pathologic changes may include one or more finding, including diffuse enlargement, dorsal or plantar margin tearing, diffuse fiber damage, fibrosis/scarring, and osseous changes. Persistent hypoechoic areas, regardless of the angle of beam incidence, are typically indicative

Figure 1. Non-weight bearing plantar approach for ultrasound investigation of the proximal metatarsus. Photo courtesy of Dr. Kurt Selberg.

of areas of fiber damage. The dorsal margin and bone-ligament interface are the most common areas injured. These types of injury typically don’t have much, if any, enlargement. Variations in anatomy do occur and are important to recognize. For example: there is a hypoechoic region both on and off angle approximately just distal to the origin of the suspensory ligament. This site may be confused for a central tear. A central tear is not common in the hind proximal suspensory ligament.

Focal or diffuse areas of increased echogenicity independent of angle of incidence are consistent fiber abnormalities (Figure 2). The dorsal aspect

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Figure 2. Lateral is to the left. Images are in non-weight bearing on (left image) and off (right image) angle images. There is a persistent area of hyperechoic fiber at the dorsolateral aspect consistent with suspensory ligament injury. The medial bone margin is focally irregular, consistent with enthesopathy. Note: The suspensory ligament does not appear enlarged. Photo courtesy of Dr. Kurt Selberg.

of the suspensory ligament is a common area of injury, often without diffuse enlargement. Measuring the cross-sectional area (CSA) can be helpful for comparing the size to the opposite limb. However, as mentioned, injuries may not have concurrent enlargement.

Measurements on the cross-sectional area of the hind suspensory ligament are not standardized for each breed and, initially, did not measure the entire ligament in a weight bearing horse.7 The normal CSA for a warmblood may not be the same as a reining Quarter Horse. For the warmblood, this may be up to 2.5 cm;7 for the Quarter Horse, it may be 1.8 cm.2 For these reasons, it is more helpful to use imaging characteristics to assess size and margin. These features of the hind limb include: loss of the normal space between the dorsal margin of the suspensory ligament and plantar bone margin, displacement of the medial plantar vessels, and extension of the ligament beyond the plantar confines of the splint bone (Figure 3). As a consequence, using the CSA only may result in underdiagnosis or, potentially, over diagnosis — pitfalls that exist in all interpretation.

Pathologic changes to the bone can occur in addition to ligamentous pathologic change or can be the primary abnormality. Abnormalities can include bone resorption, proliferation, and avulsion fragmentation.

The plantar non-weight bearing approach to evaluate the bone is equally important with the soft tissues.

Bone is also angle dependent, similar to tendons and ligaments. This means that if you are not perpendicular to the bone, the returning echo may not display as a hyperechoic line (Figure 4). Bone marrow lesions, assessed on MRI, are also common. This modality is particularly good for assessing changes to surface, cortical, and medullary portions. However, ultrasound can be superior for identifying small avulsions and enthesopathies. This is in part due to acoustic shadowing from fragmentation, good contrast between bone and ligament structures, and thin tissue sampling. The axial margins of MT2 and MT4 should 14 The Practitioner

Figure 3. Lateral is to the left in a non-weight bearing plantar approach. There is marked enlargement of the proximal aspect of the suspensory ligament.

The plantar margin extends beyond the margin of the second and fourth metatarsal bones (arrows). The medial plantar vasculature is displaced medial and plantar (arrowhead). Photo courtesy of Dr. Kurt Selberg.

also be evaluated for proliferative changes that could impinge on the suspensory ligament.

FORELIMB:

The forelimb suspensory ligament, similar to the hind, has the majority of its origin on the third metacarpus bone and smaller tendinous fibers extending proximal to the distal row of carpal bones. The proximal aspect of the suspensory ligament is bilobed. The lateral aspect is round compared to the ovoid medial portion. Located along the palmar onethird of the ligament are central areas of fat and muscle (Figure 5).

Imaging findings are similar to the hindlimb with dorsal margin fiber disruption, irregularity of the bone at the origin, and diffuse enlargement Issue 2 • 2020

Figure 4. Lateral is to the left. The left ultrasound image is from plantaromedial. Note the bone margin is ill-defined. The right image is from a plantar approach in non-weight bearing. The third metatarsal bone is hyperchoic. A focal area of mineral is in the centrodorsal aspect of the suspensory ligament (arrow). This may represent dystrophic mineralization or an avulsion fragment. Photo courtesy of Dr. Kurt Selberg.

with palmar displacement of the fat and muscle. Central tear and fiber disruption in the proximal aspect of the suspensory ligament are extremely rare. However, these types of lesions can occur with low frequency in the body of the suspensory ligament.

Typically, injuries in the proximal aspect of the suspensory ligament are best seen in an unweighted ultrasound scanning approach. In the forelimb, it is important not to flex the limb so that there is an acute angle between the radius and metacarpus.

A wide angle with the limb closer to the ground is ideal (Figure 6). This will allow the proximal most aspect of the suspensory ligament to be interrogated with relative ease, especially the bone-ligament interface where a majority of injuries occur.9 This technique is important in show jumping horses, where a lesion—especially bone resorption—may only be about 1 cm distal to the carpometacarpal joint (Figure 7).

Figure 6. Non-weight bearing ultrasound approach. Note the limb held with the foot close to the ground creating a wide (>90) angle between the antebrachium and metacarpus. This allows the proximal aspect of the suspensory to be interrogated with greater ease.

Photo courtesy of Dr. Kurt Selberg.

Figure 5. Lateral is to the left. The suspensory ligament lateral lobe is rounder and slightly thicker than the more oblong medial lobe. There is fat and muscle along the palmar one-third of the ligament (arrows). Photo courtesy of Dr. Kurt Selberg.

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In both the fore and the hind suspensory ligament injury, it is important to remember that the bone margin may remain irregular; the suspensory ligament often retains some of the initial imaging features of the injury for years, even after a return to function. The follow up exam just before a return to full function is often most critical to look for new areas of injury if the lameness relapses. Prognosis varies for a return to function, with forelimb injuries typically having better rates of return than hind suspensory injuries. The prognosis seems as though it is unrelated to the severity of the injury;9,10 however, this may change with larger imaging studies.

The proximal aspect of the suspensory ligament is a challenging area to diagnose injury. Multiple scanning techniques are often employed to make a final diagnosis. The plantar and palmar FLORIDAAEP |

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Figure 7. Lateral is to the left in a non-weight bearing image of the proximal metacarpus. In the left image, there is focal moderate bone resorption at the proximopalmaromedial aspect of the third metacarpal bone (arrow). This is at the origin of the suspensory ligament about 1.5 cm distal to the carpometacarpal joint. The right image is obtained 2 cm distal to the left image and is relatively normal.

Photo courtesy of Dr. Kurt Selberg.

non-weight bearing approaches seem to be the most effective at visualizing lesions. Correctly characterizing the lesions helps guide and target treatment options.

References: 1. Brokken M, Schneider R, Sampson S, Tucker R, Gavin P, Ho C. Magnetic resonance imaging features of proximal metacarpal and metatarsal injuries in the horse. Vet Radiol Ultrasound. 2007;48(6):507-517.

2. Barrett MF, Manchon PT, Hersman J, Kawcak CE. Magnetic resonance imaging findings of the proximal metacarpus in Quarter Horses used for cutting: Retrospective analysis of 32 horses 2009-2012. equine vet j. 2018;50(2):172-178. doi:10.1111/evj.12746.

3. Barrett MF, Selberg KT, Johnson SA, Hersman J, Frisbie DD. High field magnetic resonance imaging contributes to diagnosis of equine distal tarsus and proximal metatarsus lesions: 103 horses. Vet Radiol Ultrasound. 2018;59(5):587596. doi:10.1111/vru.12659.

4. Lempe-Troillet A, Ludewig E, Brehm W, Budras KD, Winter K, Edinger J. Magnetic resonance imaging of plantar soft tissue structures of the tarsus and proximal metatarsus in foals and adult horses. Vet Comp Orthop Traumatol. 2013;26(3):192-197. doi:10.3415/ VCOT-12-06-0072.

5. Dyson S. Diagnosis and Management of Common Suspensory Lesions in the Forelimbs and Hindlimbs of Sport Horses. 2007;6(3):179-188. doi:10.1053/j. ctep.2007.08.004.

6. Equine BJ5ACAA, 2006. Review of equine distal hock inflammation and arthritis. pdfssemanticscholarorg 7. Bischofberger AS, Konar M, Ohlerth S, et al. Magnetic resonance imaging, ultrasonography and histology of the suspensory ligament origin: a comparative study of normal anatomy of warmblood horses. equine vet j.

2006;38(6):508-516.

8. DACVR NMWD, PhD J-MDD. Imaging of the Equine Proximal Suspensory Ligament. Vet Clin North Am Equine Pract. 2012;28(3):507-525. doi:10.1016/j.cveq.2012.08.005.

metacarpus in Quarter Horses used for cutting: Retrospective analysis of 32 horses 2009-2012. equine vet j. 2017;50(2):172-178. doi:10.1111/evj.12746.

10. Norvall AP, Allen AK, Johns S, Giguere S, Selberg KT. Diagnosis, treatment, and outcome of hindlimb proximal suspensory desmopathy in sport horses: 75 cases (20082014). 2015.

Kurt Selberg, MS, DVM, DACVR

Kurt Selberg is a North Idaho native where his family owned a Quarter Horse ranch. After completing his doctorate in veterinary medicine from Washington State University, he completed an equine sports medicine internship at Virginia Equine Imaging in Middleburg, Virginia. He received his training in diagnostic imaging from Colorado State University and is a diplomate of the American College of Veterinary Radiologists. Following his residency, he completed a fellowship in advanced imaging with training from Colorado State University and from musculoskeletal radiologists in Fort Collins, Colorado. He was an assistant professor of equine diagnostic imaging at the University of Georgia for four years before returning to an equine diagnostic imaging position at Colorado State University in September 2016. His area of interest is the equine athlete and musculoskeletal diagnostic imaging.

Dr. Selberg is a certified member and lecturer at many of the International Society of Equine Locomotor Pathology (ISELP) continuing education events. He is also a FEItreating veterinarian. Most recently, he was the on-site imaging consultant for the 2018 World Equestrian Games. Aside from radiology, he also enjoys skiing, jiu jitsu, fishing, and spending time with good friends and family. He has a lovely wife Katie, two children, and two yellow dogs.

9. Barrett MF, Manchon PT, Hersman J, Kawcak CE. Magnetic resonance imaging findings of the proximal 16 The Practitioner

Issue 2 • 2020

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SUCCESS AND FAILURE IN THE ADVANCEMENT OF

EQUINE REHABILITATION PROTOCOLS TRACY A. TURNER | DVM, MS, DACVS, DACVSMR

Human physical therapy describes the care and services provided by or under the direction of a licensed physical therapist. In human medicine, physical therapists are regarded as clinicians. They engage in an examination process that includes taking the patient/ client history, conducting a systems review, and performing tests and measures to identify potential and existing problems. Based on their judgments, physical therapists provide interventions, conduct reexaminations, and modify interventions as necessary to achieve anticipated goals and expected outcomes. They are the only professionals who provide physical therapy examinations, evaluations, diagnoses, prognoses, and interventions based on the physical therapist's examination and evaluative process.

Equine rehabilitation is the application of an all-new diagnostic algorithm to our horses. It focuses upon soft tissues rather than bone and joint. It involves special tests that allow for determination of specific tendinopathies and soft tissue abnormalities. The use of objective outcome measures will be absolutely necessary, if this area is to grow. Emphasis in rehabilitation therapy is on meeting goals that are functional for the patient. The goals of rehabilitation include the restoration, maintenance, and promotion of optimal function and quality of life as they relate to movement disorders. Equine rehabilitation is in its infancy.

It is an exciting time, but we must progress carefully and look toward those with experience in this specific area. However, this does not mean that we ignore those who have been working in the field of rehabilitation for decades. These individuals may not have formal backgrounds in equine rehabilitation but have learned by trial and error what works and what doesn’t. These people may include veterinarians that have had a special interest in rehabilitation over the years but can also include technicians who have been working on the racetrack or with performance horses in charge of the rehabilitation protocols.

During rehabilitation from lameness, physical therapy may include manual techniques, an exercise-based conditioning program to activate and strengthen specific muscles, aquatic therapy, and the use of various modalities such as therapeutic ultrasound and laser. This article addresses specific areas of equine rehabilitation that fall within the realm of veterinary physical therapy and that are supported by evidence-based research.

These techniques are based in movement and locomotor sciences and the underlying concept of motor control, which is central to understanding rehabilitation from musculoskeletal injuries.

Who should be doing the rehabilitation work? The person to oversee the protocol should be the veterinarian, however the 18 The Practitioner

Horse that is almost exclusively using its forelimbs to stay both afloat and above the water. Photo courtesy of Dr. Tracy A. Turner.

veterinarian should seek advice from those who know the science of rehab and look to develop a team approach. The veterinarian will not be the one doing the rehab protocol on a daily basis, but rather the one to help organize the general protocol. The owner or a technician will typically be doing the day to day work of the rehabilitation, not unlike in the human health care system.

Rehabilitation takes time. In chronic cases, it took time for the problem to show up; therefore, it is going to take time to fix the problem. Not only does the primary problem need to be solved, but rehabilitation to improve the secondary problem of poor biomechanics must also be solved so that there is a lower chance of reinjury. In acute cases, such as trauma, the time required for rehabilitation may be shorter if there are no secondary mechanical problems that inhibit the healing process.

Rehabilitation utilizes manual therapies and therapeutic modalities. Some basic research has been done on some modalities, but more work is necessary to determine the effects these therapies have on the equine body. Through this type of basic research, the groundwork will be laid not only to determine when it would be appropriate to use a particular therapy but also the intensity and duration of treatment. For instance, under what circumstances should therapeutic ultrasound be used? Electrical stimulation?

Shockwave? Magnetic or electromagnetic therapy? Massage? It is the combination of basic research and clinical experience that will be needed to develop protocols for these modalities.

Issue 2 • 2020

Treatment and Prevention of Equine Back Pain

Back pain is recognized as a common and important cause of poor performance in athletic horses, which has stimulated clinical and research interest in the diagnosis and treatment of equine back pain. There is extensive literature describing the clinical manifestations, pathoanatomical diagnoses, treatment, and rehabilitation of back pain in people. It is known that low back pain is associated with persistent inhibition of activity in the deep spinal stabilizer muscles, specifically the multifidus and transversus abdominis. Within a matter of days after an injury such as a herniated disc, neurogenic atrophy is evident in the multifidi at the affected spinal level on the ipsilateral side.1 After back pain resolves, the atrophied muscles do not usually resume normal activation patterns unless specific therapeutic exercises are prescribed. The use of these exercises has been shown to reduce the one-year recurrence rate from 80% to about 30%.2

Flexing and extending the limb can help assess the range of motion in the joints. Photo courtesy of Dr. Tracy A. Turner.

Back pain in horses appears to follow the human model in that affected horses have atrophy of the multifidus on the affected side(s) and resolution of back pain is not necessarily accompanied by reactivation or hypertrophy of the multifidus. This is in contrast to the response of the superficial and easily palpable longissimus muscle, which may go into spasm as it attempts to compensate for the loss of spinal stability. However, the attachments of the longissimus dictate that it is more effective in moving the spine than in stabilizing the individual inter-vertebral joints. Loss of the stabilizing influence of the multifidus allows micro-motion of the intervertebral joints, which predisposes horses to the development of degenerative joint disease.

How will the process look? The process starts with an accurate Anecdotal reports suggest that dynamic mobilization exercises diagnosis and an accurate assessment of the injury. In addition, (baited stretches) performed in flexion or lateral bending are an overall assessment of the horse’s secondary or compensatory beneficial in athletic horses with back pain. The principle of these problems must be performed. This should also include an exercises is that a bait, such as a piece of carrot, is used to entice assessment of hoof balance. This will require multiple imaging the horse to move the chin to a specific position.3 The exercises modalities including MRI, ultrasound, and also radiography. In are performed in cervical flexion with the chin moving to the addition, a physiologic imaging modality like thermography may chest, between the carpi or between the fore fetlocks, in cervical be very useful in identifying the secondary problems. extension and in lateral bending to the left and right sides with the chin moving to the girth, hip, flank, or tarsus/hind fetlock.

The next step is to determine the most appropriate therapy and determine if any modality will help the healing process. This must The beneficial effect of these exercises is based on the need to be followed by the development of a protocol to restore function. activate the deep spinal musculature (multifidi) to stabilize the This is not merely healing the original injury but restoring the thoracolumbosacral spine as the head and neck assume a variety range of motion and strength. This would require a correction of extreme positions. The benefits have been confirmed in two of secondary issues as well as a correction of hoof balance issues. research studies both of which used ultrasonography to show This will require the development of new techniques to measure significant increases in the cross-sectional area of the multifidus the range of motion of horses as well as measuring strength. muscles in response to performing baited stretches regularly over This is not to mention difficulties determining the healing of a period of time. In the first study, eight school horses performed secondary issues. baited stretches five days/week for three months without any other exercise. There were significant increases in multifidus Rehabilitation of performance horses is unique because the rider CSA bilaterally at T10, T12, T14, T16, T18, and L5 together position must also be part of the solution. Rehabilitation requires with significant improvements in left:right symmetry at each of the integration of many people to make it work, which is not these spinal levels.3 A second study, conducted in race-training unlike most areas of veterinary medicine. Some people that will Thoroughbreds, found a significant increase in multifidus CSA at need to understand the rehabilitation process include the owner, T16 in horses that performed baited stretches daily for six weeks trainer, saddle fitter, farrier, nutritionist, and barn manager. in addition to their regular training program. This increase did Rehabilitation is not just the use of machines and modalities; it not occur in controls subjected to the same training program is the knowledge of how to use them in an appropriate protocol. without baited stretches.5 WWW.FAEP.NET |

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It is recommended that baited stretches be used both prophylactically and therapeutically. Three to five daily repetitions of each exercise appear to be adequate to restore or maintain activity and strength of the multifidus.

Proprioceptive Stimulation

Following recovery from orthopedic injury, gait deficits may persist due to soft tissue stiffness, muscle atrophy, altered neuromotor coordination patterns, or inhibition of specific muscles. These deficits do not necessarily resolve spontaneously with normal exercises and training.6 During rehabilitation, physical therapy is used to restore function in terms of range of joint motion (ROM), muscle activation, and muscular coordination and strength. Muscle strength and endurance are improved by increasing the intensity or number of repetitions, respectively, of exercises targeted at recruiting specific muscles.

Sometimes a muscle becomes inhibited as a consequence of a minor trauma involving pain or capsular distension. This type of inhibition usually involves the deep stabilizing muscles of a joint rather than the prime movers. The result is joint instability that predisposes to degenerative changes due to micromotion of the joint. A well-documented example in the human field is the development of patellofemoral pain following a minor pathology such as distension of the femorotibial joint. This leads to altered knee joint proprioception and changes in the activation sequence of the different heads of quadriceps femoris. Vastus medialis obliquus, which is a deep stabilizer of the knee, shows delayed onset of activity leading to a wide range of effects including maltracking of the patella and loss of strength in the external rotators and abductors of the hip. Evidence-based studies support the use of physiotherapeutic treatment targeting vastus medialis obliquus through taping, bracing, and various forms of therapeutic exercise.7 In horses, little is known about the deep stabilizing musculature in locations other than the spine and there are no evidence-based reports of the effect of therapeutic exercises on specific muscles

Thermograph shows the horse out of the water, note the increased heat over the muscles of the forelimb.

Photo courtesy of Dr. Tracy A. Turner.

in the limbs. However, there have been reports of the effect of techniques that change the range of motion of the joints through stimulation of muscle activity.

Trot poles. Trotting over poles is used therapeutically to restore full ranges of joint motion in the limbs. The kinematics and kinetics associated with trotting over poles on the ground (11 cm high) and raised poles (20 cm high) have been reported. 8,9 Peak heights of the fore and hind hooves increased significantly and progressively from no poles (fore: 13.8±3.8 cm; hind: 10.8±2.4 cm) to low poles (fore: 30.9±4.9 cm; hind: 24.9±3.7 cm) and to high poles (fore: 41.0±3.9 cm; hind: 32.7±4.0 cm).

Peak hoof heights when trotting over poles were higher than with tactile bracelets or leg weights. All joints of the fore and hind limbs contributed to the increase in hoof height through increased swing phase flexion.

There were no changes in peak vertical force or in the degree of fetlock extension when trotting over poles, suggesting that loading of the musculoskeletal tissues is comparable with that associated with trotting on level ground at the same speed.

This makes it unlikely that trotting over poles will jeopardize the recovery process by over-loading the limbs. Peak forelimb braking force increased, and the transverse impulse changed from being directed medially when trotting on level ground to laterally directed when trotting over poles. This was interpreted as a mechanism to enhance balance and suggests that the adductor musculature is being recruited.

Compression boots: apparatus that compresses distal to proximal, increasing the limb temperature and, therefore, the circulation in the forelimb. Photo courtesy of Dr. Tracy A. Turner.

20 The Practitioner

Unlike the use of proprioceptive stimulation devices, in which the effects decrease over time due to habituation, the horse is required to elevate the hooves to ensure clearance whenever poles are present. The need to raise the limbs sufficiently to clear the poles and to adjust the step length so the hooves are placed accurately also requires visuomotor coordination, which suggests an application in rehabilitating neurological cases.

Issue 2 • 2020

3. Stubbs NC, Kaiser LJ, Hauptman J, et al. Dynamic mobilization exercises increase cross sectional area of musculus multifidus. Equine Vet J 2011;43:522-529.

4. Stubbs NC, Clayton HM. Activate your horse's core. Sport Horse Publications, 2008:Mason, MI. 5. Tabor GF, Johansson C, Randle H. The effects of dynamic mobilization exercises on the multifidus muscle in thoroughbred racehorses, In: 8th International Equitation Science Conference, Edinburgh, Scotland, 2012:64.

6. Van Harreveld PD, Lillich JD, Kawcak CE, et al. Clinical evaluation of the effects of immobilization followed by remobilization and exercise on the metacarpophalangeal joint in horses. Am J Vet Res 2002;63:282-288.

Whole body thermal image. Thermography can be used to assess changes in circulation caused by devices or exercise. The author finds this a very helpful tool in the diagnosis and assessment of rehabilitation. Photo courtesy of Dr. Tracy A. Turner.

Measurement of Success and Failure

In the equine field, we have a tendency to measure outcome simply by whether the horse returns to its previous level of work.

While this is practical in nature, the fact is horses get better or not.

There are numerous studies showing the effects of surgery or other therapies on these outcomes. But when considering the goals of rehabilitation, we must ask: is this the correct question? The goals of rehabilitative therapy are to improve strength, flexibility, and endurance. It is predicated on the healing of the injury and the restoration of the injured area to “normal.”

If we are to measure success or failure, we need to make the appropriate measure. If we are going to develop or modify protocols, we need to measure correctly. How do you measure strength in a horse? How do you measure flexibility? Is range-ofmotion an appropriate measure for flexibility? If so, what are the normal parameters. Finally, what is the measure of endurance?

How much endurance does an occupation need?

Success occurs for many reasons: surgery or other therapies have successfully healed the issue; the extent of the injury was not as serious as a different case; owner compliance (this cannot be stressed enough); and stoicism of the horse. The point is that the success or failure of rehabilitation cannot be measured by the horse’s return to a previous level of work but should be judged (measured) on whether the goals were achieved.

References: 1. Hodges P, Holm AK, Hansson T, et al. Rapid atrophy of the lumbar multifidus follows experimental disc or nerve root injury. Spine 2006;31:2926-2933.

2. Hides JA, Jull GA, Richardson CA. Long-term effects of specific stabilizing exercises for first-episode low back pain. Spine 2001;26:E243-248.

WWW.FAEP.NET |

7. Crossley K, Bennell K, Green S, et al. A systematic review of physical interventions for patellofemoral pain syndrome. Clinical journal of sport medicine: official journal of the Canadian Academy of Sport Medicine 2001;11:103-110.

8. Brown S, N C Stubbs, L J Kaiser, M Lavagnino, H M Clayton Swing Phase Kinematics of Horses Trotting Over Poles Equine Vet J . 2015 Jan;47(1):107-12. doi: 10.1111/ evj.12253. Epub 2014 Apr 9.

9. Clayton HM, Stubbs NC, Lavagnino M. Stance phase kinematics and kinetics of horses trotting over poles.

Equine Vet J. 2015 Jan;47(1):113-8. doi: 10.1111/evj.12251.

Epub 2014 Apr 7.

Tracy A. Turner, DVM, MS, DACVS, DACVSMR Dr. Tracy A. Turner received his DVM degree from Colorado State University in 1978 and interned at the University of Georgia. He completed a surgical residency and master’s degree at Purdue University.

He has served on the faculties of the University of Illinois, University of Florida, and the University of Minnesota.

He joined Anoka Equine Clinic in Elk River, Minnesota in 2004 and started his own practice in 2016 (Turner Equine Sports Medicine and Surgery), where he practices sports medicine, lameness, and surgery. Dr. Turner's primary areas of research interest have focused on equine lameness with interest in equine podiatry and thermography. He has spoken nationally and internationally on lameness topics.

He has written more than 100 peer-reviewed manuscripts, more than 250 non-peer-reviewed papers, and more than 30 book chapters on equine lameness, podiatry, and thermography. Dr. Turner is a diplomate of the American College of Veterinary Surgeons, a diplomate of the American College of Sports Medicine and Rehabilitation, and is a Fellow of the American Academy of Thermology.

He is an active member of the AVMA, the AAEP, the American Horse Council, and the Minnesota Horse Council.

FLORIDAAEP |

@FLORIDA_VMA | The Practitioner 21

There’s nothing else like it.

Over the past 30 years, Adequan® i.m. (polysulfated glycosaminoglycan) has been administered millions of times1 to treat degenerative joint disease, and with good reason. From day one, it’s been 2, 3 the only FDA-Approved equine PSGAG joint treatment available, and the only one proven to.

Reduce inflammation Restore synovial joint lubrication Repair joint cartilage Reverse the disease cycle When you start with it early and stay with it as needed, horses may enjoy greater mobility 2, 4, 5 over a lifetime. Discover if Adequan is the right choice. Talk to your American Regent Animal Health sales representative or call (800) 458-0163 to order.

BRIEF SUMMARY: Prior to use please consult the product insert, a summary of which follows: CAUTION: Federal law restricts this drug to use by or on the order of a licensed veterinarian. INDICATIONS: Adequan® i.m. is recommended for the intramuscular treatment of non-infectious degenerative and/or traumatic joint dysfunction and associated lameness of the carpal and hock joints in horses. CONTRAINDICATIONS: There are no known contraindications to the use of intramuscular Polysulfated Glycosaminoglycan. WARNINGS: Do not use in horses intended for human consumption. Not for use in humans. Keep this and all medications out of the reach of children. PRECAUTIONS: The safe use of Adequan® i.m. in horses used for breeding purposes, during pregnancy, or in lactating mares has not been evaluated. For customer care, or to obtain product information, visit www.adequan.com. To report an adverse event please contact American Regent, Inc. at (800) 734-9236 or email pv@americanregent.com.

Please see Full Prescribing Information at www.adequan.com.

www.adequan.com 1 Data on file.

2 Adequan® i.m. Package Insert, Rev 1/19.

3 Burba DJ, Collier MA, DeBault LE, Hanson-Painton O, Thompson HC, Holder CL: In vivo kinetic study on uptake and distribution of intramuscular tritium-labeled polysulfated glycosaminoglycan in equine body fluid compartments and articular cartilage in an osteochondral defect model. J Equine Vet Sci 1993; 13: 696-703.

4 Kim DY, Taylor HW, Moore RM, Paulsen DB, Cho DY. Articular chondrocyte apoptosis in equine osteoarthritis. The Veterinary Journal 2003; 166: 52-57.

5 McIlwraith CW, Frisbie DD, Kawcak CE, van Weeren PR. Joint Disease in the Horse.St. Louis, MO: Elsevier, 2016; 33-48.

All trademarks are the property of American Regent, Inc. © 2020, American Regent, Inc. PP-AI-US-0372 02/2020

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FLORIDAAEP |

@FLORIDA_VMA | The Practitioner 23

IMPROVING PRACTICE PROFITABILITY AMY L. GRICE | VMD, MBA

The path to improving profitability requires you to maximize your revenue and minimize your expenses. This is based on the profit equation:

Revenue – Expenses = Profit The Importance of Profit

Veterinarians are empathetic, kind, and giving human beings.

Often, they feel that making a profit, particularly connected to others’ misfortune, is wrong. However, the viability and value of a practice is markedly impacted by its profitability. Profit is necessary to pay loan payments and interest, to fund employees’ pay raises, to purchase equipment, to build practice value beyond the fair market value of the business’s assets, and as an incentive to own a business. Profit is highly dependent on the owner’s decisions on pricing, inventory management, discounting, and expense management.

There are only three ways to make more money in a veterinary business: • Work more - increase the number of hours you work.

• Charge more - increase the fees you charge or the revenue you earn for the hours you work (spend more of your time on the most profitable services).

• Spend less - decrease the expenses incurred while doing the work.

24 The Practitioner

Many veterinary business owners look proudly at the amount of gross revenue their practice produces, and neglect to look at their profitability. The value of a practice depends on its profitability. Many professional service businesses (engineers, accountants, dentists, etc.) have profit margins of 20% or more, and veterinarians should aspire to have this level of return as well.

Similar businesses in the same industry, in the same location, can have very different valuations because they can have very different profitability. Many practice owners need the sale of their practice to help fund their retirement; unfortunately, many are surprised at the time of retirement that their practice is worth much less than they expected. While these practices may have high revenue, they may have very limited profit. Low profit equals low value. A consistent history of robust profit supports a high value for the sale of a practice.

Issue 2 • 2020

Figure 1. Changes to EBITDA because of a 5% increase in fees.

The Profit and Loss Statement

The profit and loss statement lists and categorizes the various revenues and expenses that result from operating a business during a given period - a year, a quarter, or a month. The sum of revenues (+) and expenses (-) represents a company's net income or net loss during that period. The broad categories of expenses in a veterinary practice include cost of professional services (drugs, supplies, laboratory, etc.), payroll and employee costs, administrative costs, collection costs, and facility and equipment costs. When these expenses are subtracted from revenue, the result is net ordinary income, or EBITDA (earnings before interest, taxes, depreciation, and amortization). Items paid from this profit include taxes, loan principal and interest payments, discounts, employee raises and bonuses, new equipment bought with cash, and a return on investment for being a business owner.

Kelly Lyons and Murray Lyons’ book, The 1% Difference, details how small changes to the profit & loss statement can have a big impact on profitability. Although it is not intuitive, a 1% change to revenue or expenses can change bottom line results by much more than 1%. Increased profitability often does not require big changes. It is equally important to note that small changes in your income statement can affect your business in a negative way too. A small decrease in revenue or a small increase in expenses can have a marked negative effect on profit.

WWW.FAEP.NET |

FLORIDAAEP |

@FLORIDA_VMA | The Practitioner  25

Figure 2. Changes to EBITDA because of a 5% increase in fees when unprofitable.

As an example, we will utilize the income statement of a hypothetical ambulatory equine practice that has a gross revenue of $2,000,000 (Figure 1). This practice has typical expenses and a net ordinary profit of 9.95% before the fee increase. A 5% increase in fees results in a $100,000 (50.3%) increase in EBITDA, from $198,900 to $298,900. Thus, for each 1% increase in fees, there was a 10% multiplier on the bottom line!

The lower the profit is, the bigger the impact an increase in revenue will have. If we look at a practice that has no profit at all (Figure 2), increasing fees by 5% will increase EBITDA by over 8000%. Increasing revenue through increases in fees has the greatest single impact to the bottom line.

Applying 5% changes to other aspects of the income statement by reducing different categories of expenses has an impact greater than 5%, but nothing increases EBITDA like increasing fees. The key to the best profitability lies in reducing expenses, maximizing revenue by collecting for all the work you do, and charging fees appropriate for your level of professional education.

26 The Practitioner

Concept of Revenue Wholeness

Revenue has a significant effect on profitability, as many practice expenses are fixed and do not increase with the amount of revenue earned. Once these fixed expenses are paid, along with the variable expenses of drugs, supplies, and employee wages, additional revenue creates higher profits. When a practice owner or manager examines financial reports, expenses sometimes appear to be excessive as a percentage of the total revenue when compared to external benchmarks or even to previous practice performance. The natural reaction is to immediately want to cut costs. However, because many costs are relatively fixed and most of the practice’s variable expenses are crucial to earning revenue, it is often the revenue that must increase in order for the percentage of expenses to decrease. While paring unnecessary or excessive expenses is appropriate, remember that you must spend money to make money.

Practice owners sometimes lose sight of the fact that managing and maximizing revenue provides the best opportunity to increase profitability. Increased revenue does not always have to come from working more hours or charging higher prices, sometimes it comes from achieving revenue wholeness. Revenue

Issue 2 • 2020

wholeness is defined as capturing all the fees and value that are provided when services are rendered, or products are sold.

loss. It is important to keep this in mind when you decide on product pricing and when you are writing invoices.

Revenue wholeness is the single most important driver of healthy revenue, healthy expense percentages, and healthy profit. The importance of capturing all the potential value of your practice’s activities is illustrated below (Figure 3). When revenue potential leaks away through a failure to charge for all services or products, or through discounting, the effect can be catastrophic.

Invoice auditing can be used to uncover revenues that may have been missed. Invoice auditing is simply a review of what was charged compared with what was actually done at the appointment. This strategy will uncover missed revenue opportunities and will allow you and your team to see where you must pay closer attention. Simply by making everyone aware of how easily charges are missed, you will affect the outcome. If you are failing to capture an average of 10-20% of your revenue, think of the effect that is having on your profit.

Achieving Whole Revenue

Invoice review can identify charges that were missed for services performed and medications dispensed. Before finalizing an invoice, have your assistant review it for errors if you prepared it and vice-versa. If you are alone, write the invoice before you clean up, and then, afterward, recheck it a second time before finalizing it. Methodically review the sequence of the call’s events, examination, or day of hospitalization. Sedation administered, supplies dispensed, and medications are a large source of missed charges in most practices.

Because dispensed items cost the practice money and, in many cases, have a small mark-up, you may need to sell several of the item in the future just to break even if you forget to bill for the item even once. For example, if you have a dispensed medication that costs you $30 and you sell it for a 40% markup ($42) in order to compete with online pharmacies, you will make $12 over your cost on each bottle. That means if you fail to charge for one bottle, you need to sell two-and-a-half more bottles just to recoup your

The invoice auditing process starts with a review of a group of invoices. An invoice group may be chosen based on particular criteria. For instance, you could choose to audit a particular area of the practice (e.g. surgical cases, outpatient cases, farm call cases), a particular person/group of people involved (e.g. Doctor A, Technician B, interns), or all invoices during a particular block of time or day of the week (e.g. weekends). Compare the invoice items with what is in the medical records and note any discrepancies in fees not charged and/or discounts that were given that did not meet the criteria of your planned discount strategies.

This will show the difference in the invoice as it should have been charged from the actual in both dollars and as a percent of the total. Reviewing 15-30 invoices will provide a typical picture of what percentage of the full potential revenue is being missed. You will also determine what types of revenue are most commonly missed, such as dispensed medications, bandages, or second

Figure 3. Effect on EBITDA when there is a failure to capture “whole” revenue.

WWW.FAEP.NET |

FLORIDAAEP |

@FLORIDA_VMA | The Practitioner 27

doses of sedation. This exercise reveals low-hanging fruit and can instantaneously increase your revenue.

A further step that can be taken to address revenue wholeness involves medical record auditing. Medical record auditing is the process of reviewing presenting complaints and the course of medical actions offered and accepted. It is always a good idea for veterinarians working in the same practice to have similar diagnostic and treatment plans for common clinical presentations. Client confidence and trust is enhanced when a practice has congruity in their operating procedures. The same criteria as outlined above, along with a particular diagnostic code or presenting complaint can be utilized for the audit. Failure to offer an array of available diagnostic and treatment choices can truncate your revenue potential.

Not achieving revenue wholeness can have drastic effects on your practice’s profitability. Ways to increase your revenue capture include awareness, invoice review, invoice auditing, medical records review, and minimizing discounts. Failure to capture all the revenue from the work you do has marked effects on the profit your practice earns. Because profit affects practice value, the ability to fund equipment purchases, the chance to give raises, owner compensation, and the viability of the business, it is essential to maximize revenue collection from the work you do and minimize expenses.

Amy L. Grice, VMD, MBA

The results of auditing medical records should provide good collaborative fuel for robust discussion among the veterinary team. While equine veterinarians value independent decisionmaking, collaboration to form broad standards of care will strengthen the practice brand measurably. As a practice owner, it is important to know that the patient-client care provided is in alignment with the mission, values, and vision of the practice.

Medical record auditing is a snapshot of this performance.

Dr. Grice was an ambulatory equine practitioner in the Hudson Valley of New York for 25 years, and served as the managing partner of the 13 doctor equine referral hospital in Rhinebeck, New York. At the end of 2014, she retired from clinical practice to concentrate on veterinary business consulting and moved her residence to Virginia City, Montana.

Many times, lost revenue comes from discounting. Discounting can be planned or unplanned. Planned discounting is a marketing strategy to drive revenue. However, unplanned discounting can cause a serious erosion of profit. It can be very hard to control your urge to offer a discount in the face of emotional situations where you feel compassion and a desire to help the clients and patients you care about. Typically, veterinarians give discounts when clients are not expecting one. Sometimes our immediate reaction to a complaint or conversation about fees is to offer a discount when compassionate listening and validation may be all the client really needs. Remember that your practice will not remain viable if you do not make a profit. Your staff and your family depend on your practice’s profitability for their future. As a veterinarian, you must have empathy, but there is no requirement that you must live in poverty!

Dr. Grice received her B.A. in biology from Wellesley College in Massachusetts and completed her veterinary education at the University of Pennsylvania's School of Veterinary Medicine in 1990. She earned her MBA with a concentration in ethical leadership from Marist College School of Management in 2014.

Planning for compassionate discounting may take the form of an “Angel” fund that clients can donate to, or a certain dollar figure that each veterinarian may use for discounting each year.

Veterinarians typically come to their career because of a love for animals, so having a mechanism for providing compassionate care is essential for feeding their soul. Other planned discounting can drive business and cash flow during slow seasons. For example, you may waive farm calls for routine dental services performed during winter months.

Think about these questions: • Where is your practice failing to capture all of the revenue that you produce?

• How much revenue do you think your practice is failing to capture?

28 The Practitioner

Dr. Grice is a member of the American Association of Equine Practitioners, where she served on the board of directors from 2015-2018, and currently serves on several task forces. She is currently serving as a member of the AVMA Economic Strategy Committee. Dr. Grice is a frequent speaker at educational seminars for veterinarians both nationally and regionally, as well as facilitating regional Decade One networking groups for veterinarians early in their careers. In addition, she collaborates with industry partners to bring business education to veterinarians and consults with a diverse range of veterinary businesses. Dr. Grice aids with transitions of ownership, strategic planning, financial projections, and other solutions for private practitioners.

Issue 2 • 2020

BECOME AN

Educational Partner!

When you become an educational partner, you:

CLASS-LEADING EQUINE WELLNESS SOLUTIONS Zoetis offers the vital products your practice needs from vaccines to dewormer products.

• Support the advancement of the equine veterinary profession • Gain the trust and support of members • Your logo will be advertised ▶ online ▶ in The Practitioner & at our educational events

For more information on becoming an Educational Partner, please contact the FAEP at 800.992.3862 or email info@fvma.org.

Offering for Sale Equine Practice on the Space Coast

• • • •

A very unique opportunity 2 Doctor turnkey operation with office, barn, treatment area, and paddocks.

2019 gross revenue of $670K Digital-Xray and Ultrasound Great opportunity to expand and capitalize on the resurgence of the Space Coast.

Contact Dr. Richard Alker for further practice information.

850.814.9962 or Richard@tpsgsales.com Showcase Properties of Central Florida, Broker All trademarks are the property of Zoetis Services LLC or a related company or a licensor unless otherwise noted. © 2019 Zoetis Services LLC. All rights reserved. GEQ-00533

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What’s your vision for the future of your practice?

Questions to ask as you enter discussions with potential partners.

NO.

01

Is it the right culture fit for your team?

As you begin considering your options for selling your practice, it’s important to find a partner aligned with your values, respectful of the individuality of what you’ve built, and equipped to grow your business, while your team and culture remain intact.

Ask around to find out which buyers have the best reputation for investing in the animal health care profession, and the equine community specifically.

NO.

02

Do the partnership options make sense?

Because selling your practice is such a personal decision, you’ll want to understand what types of options are available, and to what level they can tailor the terms to meet your needs.

YO U R O P T I O N S: • Selling 100% or staying onboard in a joint venture

• Selling your property or renting it to the buyer

• Providing the opportunity for your associates to buy in

NO.

03

How comprehensive are the support services?

As you contemplate transitioning your business, you’ll want to know every aspect is covered. Seek out a partner with a dedicated team seasoned in everything from marketing and recruiting, to IT, HR, accounting, taxes, legal and more. Ask about access to capital for new equipment and renovations as well.

Connect with us at 888.767.7755 and info@nva.com or visit us at nva.com.

NVA has over 800 partnerships in the US, Canada, Australia, New Zealand and Singapore. Our veterinarians provide a full range of medical and surgical services, and our passionate, visionary local hospital and pet resort leaders embody NVA’s unique entrepreneurial spirit. We’d be more than happy to talk through your questions and concerns. You can reach us at 888.767.7755 | info@NVA.com.

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