PEDIATRICS
• Fractures that are unique to children:
Greenstick fractures are the most common fracture pattern in children. They are an incomplete fracture at the metaphysis-diaphysis junction with one cortex remaining intact.
Torus fractures are also called ‘buckle’ fractures and are also at the metaphysis-diaphysis junction. They are typically the result of compressive forces.
Salter-Harris Fractures
▶ Fractures involving the growth plate can lead to growth complications: don’t miss these!
▶ Salter-Harris fractures are frequently seen in the long bones of children
▶ An easy mnemonic: SALTER
◆ Type I = Slip (fracture of the physis); may look normal on xray
◆ Type II = Above (fracture above physis)
◆ Type III = Lower (fracture below physis)
◆ Type IV = Through (fracture through metaphysis, physis, and epiphysis)
◆ Type V = ERasing the growth plate – this is the worst type as
disruption of the growth plate causes disruption of growth
A 7 year old child presents after jumping off of a five foot ladder and landing on his feet. He is unable to bear weight due to pain. X-rays of his foot are unremarkable; the ankle is shown below. Which of the following is the most likely diagnosis?
A) Salter-Harris type 1
B) Salter-Harris type 2
C) Salter-Harris type 3
D) Salter-Harris type 5
E) None of the above
Answer: D
Explanation: X-rays are often negative with type 1 and type 5 injuries. A missed diagnosis of a type 5 fracture carries the worst prognosis as it can prevent further bone growth. Type 5 fractures are rare and typically follow direct axial compression.
• In general, it’s more common for children to have an injury to the bone than the ligament. Have a low threshold to obtain imaging studies in children and be wary of routinely diagnosing ‘sprains’.
• Child abuse should be considered in any pediatric fracture, in
particular:
▶ Bucket handle or ‘chip’ fracture = epiphyseal fractures from a child being grabbed/shaken; can be bilateral and most involve the tibia or femur
▶ Mid-shaft humerus fracture (supracondylar fractures are usually accidental, but mid-shaft fractures require a lot of force)
▶ Mid-shaft tibia fracture (distal tibia fractures are less suspicious)
▶ Vertebral compression fractures
▶ Rib fracture = in particular the lateral and posterior parts of a rib
A skeletal survey is a series of x-rays of most of the major bones of the body and should be done in all cases of suspected child abuse. It consists of: AP views of the arms, forearms, hands, thighs, legs, feet, abdomen, and pelvis; AP and lateral views of the cervical, thoracic, and lumbar spine as well two views of the skull.
When you think about fingertip infections in the ER, there are three things that should come to mind:
1) Paronychia – infection around the nail fold most commonly caused by S. aureus. Besides drainage, treatment typically includes oral antibiotics.
2) Felon – infection of the distal pulp again most commonly caused by S. aureus. If left untreated, it can lead to osteomyelitis or tenosynovitis. Most patients require drainage and antibiotics. Drainage of felon: make a lateral fingertip incision (meaning the thumb and fifth finger are incised radially, and others are done on the ulnar side)
3) Herpetic whitlow – painful lesion at the fingertip caused by HSV. It’s typically seen in dishwashers and dental hygienists and unlike the other two, drainage will lead to spread of infection. Put the scalpel away!
• Boutonniere deformity: extensor tendon central slip
Meaning? The joint is stuck in PIP flexion and DIP hyperextension
Why does it happen? It can be due to an injury (laceration, jammed finger) or a chronic condition like arthritis What should I do? Splint the PIP joint in extension
If not treated promptly, the deformity can become permanent (surgery may be necessary)
• Mallet Finger
▶ Extensor tendon rupture or avulsion fracture at base of distal phalanx
▶ Caused by forced flexion of DIP often from a direct blow to the tip of the finger (for instance a basketball ‘jamming’ the fingertip)
▶ Treatment: splint distal tip in extension
• Jersey Finger
▶ Avulsion of the FDP at the level of the DIP joint (tendon retracts to the level of the PIP and may be palpated on exam)
▶ Frequently involves the ring finger and causes all fingers to
contract as a result
▶ Treatment: surgical repair
A bodybuilder presents after dropping a dumbbell on his little pinky finger approximately 36 hours ago. X-rays are negative for fracture. Which of the following is the most appropriate management?
A) Reassurance and discharge
B) Trephination
C) Trephination and antibiotics
D) Remove the nail, repair any nailbed laceration, and reattach the nail loosely
Answer: B
Explanation: Patients with subungual hematomas and pain should undergo trephination for pain relief if the injury is less than 48 hours old. Beyond 48 hours, most hematomas have clotted and trephination is unlikely to be of benefit. Of note, small nailbed lacerations with an intact nail are not an indication for nail removal.
An 18 year old male presents to the ER with pain in his right thumb. He was playing football and the ball came in faster than he expected – when he went up for the catch it bent his thumb back. He now has difficulty pinching his thumb and index fingers together. Which of the following is most likely injured?
A) Flexor digitorum superficialis
B) Radial collateral ligament
C) Ulnar collateral ligament
D) Extensor tendon
E) Median nerve
Answer: C
Explanation: This patient likely has ‘gamekeeper’s thumb’, also known as ‘skier’s thumb’. The hallmark symptom is weakness of the pincer grasp. If the ulnar collateral ligament is completely torn, surgery may be required and Stener lesions may develop. If partially torn, the ligament may heal with rest and a thumb spica splint. Gamekeeper’s thumbs are often associated with avulsion fractures at the base of the thumb as well.
Gamekeeper’s thumb: > 30° joint laxity when radial stress is applied to the thumb MCP
• Metacarpal Fractures
▶ Metacarpal neck fractures warrant reduction if angulation is more than:
10 degrees in index or middle finger
20 degrees in ring finger
◆ 40 degrees in small finger
▶ Boxer’s fracture = fracture of the neck of the 5th metacarpal
▶ Always assess metacarpal neck fractures for rotational deformity
Have the patient make a fist and see if the fingers cross – if the fingers overlap at all, this ‘rotational deformity’ should be corrected as it can lead to real disability
How does one reduce a metacarpal neck fracture?
After appropriate anesthesia, place the finger parallel to the floor. The MCP joint should be flexed to 90 degrees so that the finger is pointing downwards. Put downward pressure on the metacarpal shaft while applying upward pressure to the phalange.
Open metacarpal fractures do not necessarily require that the patient make a stat trip to the OR for irrigation/washout. If there is no evidence of gross contamination, it may be reasonable to perform a good thorough bedside irrigation and discharge the patient home with antibiotics and close followup. This is different from the way long bone fractures are managed: an open long bone fracture traditionally needs urgent washout.
Be familiar with the difference between a Bennet’s Fracture and a Rolando Fracture:
• Bennet’s Fracture
▶ Fracture at base of 1st metacarpal
▶ Intra-articular
• Rolando Fracture
▶ Fracture at base of 1st metacarpal
▶ Comminuted intra-articular
Fight bite: when a fist strikes teeth, the guy with that fist needs antibiotics. If he has a fracture he probably needs IV antibiotics for an open fracture. Fight bites are highly prone to infection since the extensor tendon and MCP joints are relatively avascular and therefore have limited ability to combat infection. The 3rd MCP joint of the dominant hand is most often affected. If left untreated, these can lead to tenosynovitis.
Ever wish there were some criteria to identify who might have
tenosynovitis? Thankfully, Dr. Kanavel felt the same way:
• Kanavel’s signs for flexor tenosynovitis
▶ Fusiform swelling, ‘sausage digit’
▶ Finger stuck in flexed position
▶ Pain with extension (earliest sign)
▶ Tenderness along the flexor tendon
• High Pressure Injection Injury (for instance a paint gun injection into the hand) – don’t fall asleep on these! They may appear benign early but can rapidly lead to compartment syndrome or ischemia. Get an xray, start antibiotics, and call the orthopedist
Boards likes to ask for the ‘next best step’ even when you would do multiple things at once. If given the choice, consult orthopedic surgery first.
• What to do if someone accidentally injects an epi-pen into their fingertip?
◆ Apply topical nitroglycerin paste to the affected area, place a glove over the paste, and place the hand in warm water (vasodilation)
◆ If still painful, inject phentolamine locally. Some sources say to go straight to the phentolamine so if you see a question about this, phentolamine is probably the answer they’re looking for.
WRIST
• Colles Fracture
▶ Most common fracture in adults age > 50
▶ Distal radius fracture with dorsal displacement
▶ Frequently associated with an ulnar styloid fracture
▶ Important to assess median nerve for injury
▶ Treatment: closed reduction
• Smith Fracture
▶ ‘Reverse Colles’
▶ Distal radius fracture with volar displacement
▶ Treatment: closed reduction
• Barton’s Fracture
▶ Distal radius fracture with dislocation of radiocarpal joint
▶ Most common fracture-dislocation of the wrist
▶ Most will require external fixation/surgical treatment
A 50 year old woman was chasing her cat and tripped over another cat. She fell onto an outstretched hand to avoid landing on a third cat. The fourth cat called 911 and she is now in your ER. She has anatomic snuffbox tenderness and x-rays are unremarkable. Which of the following is most appropriate?
A) Discharge home with reassurance
B) If the patient still has pain, recommend an MRI to evaluate for ligamentous injury
C) Consult orthopedic surgery
D) Splint the patient and have them follow up
Answer: D
Explanation: The scaphoid is the most frequently fractured carpal bone, but it is prone to not healing well due to its unique blood supply. Blood supply to the bone is from distal to proximal – since most fractures occur in the
middle 1/3rd of the scaphoid, many fractures are prone to avascular necrosis. This is why even patients with negative x-rays but suspicion for scaphoid fracture should have a thumb spica splint placed and outpatient follow-up.
Most people already know that the scaphoid is the most frequently fractured carpal bone.
Did you know the triquetrum is the second most frequently fractured?
• Scapholunate Dissociation
▶ Most common ligamentous injury of the hand
▶ > 3 mm separation is suggestive of scapholunate dissociation
▶ > 5 mm separation between scaphoid and lunate confirms the diagnosis
▶ Treatment: thumb spica splint, orthopedic referral for operative repair
• A frequently seen and frequently missed distinction is that of a lunate from a perilunate dislocation:
▶ Lunate Dislocation: lunate is displaced but the capitate is still aligned Perilunate Dislocation: lunate is aligned but all other
carpal bones are displaced
Perilunate dislocations classically have a ‘pie-shaped’ lunate on the AP view.
But the real diagnosis is made on the lateral film…
In the first image the lunate itself is dislocated anteriorly. In the second image, all the bones around the lunate (PERI-lunate) are dislocated posteriorly
• Carpal Tunnel Syndrome
▶ Entrapment of the median nerve
▶ Risk factors: pregnancy, diabetes, hypothyroidism, rheumatoid arthritis Phalen’s sign = hyperflexion of both wrists → paresthesias in median nn Tinel’s sign = tapping volar wrist → paresthesias in median nn
▶ Both Phalen’s and Tinel’s have poor sensitivity and specificity.
▶ Most sensitive finding: abnormal sensation of the distal tip of the index finger
▶ In general, sensory findings present much earlier than motor ones
▶ Treatment: splint, NSAIDs, steroid injections, surgery
• Guyon’s Canal Syndrome
▶ Guyon’s canal is formed by a ligament connecting the pisiform to the hamate and contains the ulnar nerve
▶ Symptoms: numbness/tingling in ulnar distribution
▶ Caused by repetitive trauma (bicyclists holding handlebars, players holding golf clubs or baseball bats)
▶ Treatment: splint, surgery for decompression
• DeQuervain’s Tenosynovitis
▶ Overuse of the extensor pollicis brevis and the abductor pollicis longus
▶ Finkelstein’s test = ulnar deviation of fist reproduces pain
▶ Treatment: splint, NSAIDs
A well-known alcoholic patient presents to the ER with wrist drop. He says he was out celebrating last night because it was his birthday. So what do you think happened? He probably partied a little too hard and passed out while sleeping on his arm all night – compressing his radial nerve. Prognosis? It can take days to years for the wrist drop to resolve depending on the extent of the compression. Treatment is to splint the wrist in extension.
