Vertebral Columns International Society for the Advancement of Spine Surgery
Spring 2017
Boca Raton Resort & Club, Home of ISASS17
In This Issue FUSION Cellular Bone Allografts in Spinal Fusion: Where Are We Now?........... 3 CERTIFICATION Update on ABNS Exams........................................................................ 7 NEW TECHNOLOGY Adopting New Technologies & Techniques...........................................9 IMPROVEMENT What It Means to Be a “Spince Center of Excellence”.........................11
Editor in Chief Kern Singh Editorial Board Matthew Colman, MD Jeffrey Goldstein, MD Jonathan Grauer, MD Hamid Hassanzadeh, MD Safdar Khan, MD Mark Kurd, MD Yu-Po Lee, MD Vikas Mehta, MD John O’Toole, MD Alpesh Patel, MD Sheeraz Quereshi, MD Kris Siemionow, MD Seth Williams, MD Publisher Jonny Dover
Vertebral Columns is published quarterly by the International Society for the Advancement of Spine Surgery. © 2017 ISASS. All rights reserved. Opinions of authors and editors do not necessarily reflect positions taken by the Society. This publication is available digitally at https://vertebralcolumns.com. ISSN 2414-6277. 2
Vertebral Columns • Spring 2017
FUSION
Cellular Bone Allografts in Spinal Fusion: Where Are We Now? Nikhil Jain, MD Safdar N. Khan, MD Spinal fusions account for more than 400,000 spinal surgeries performed in the US annually with an estimated national bill of more than $33,000,000,0001. Parallel to this growth over the years has been the enthusiasm to find an ideal bone graft for fusion. An ideal graft must possess three properties for bone fusion – osteoconduction, osteoinduction and osteogenesis. Despite the fact that the “gold standard” autograft has all these properties, its use has largely fallen out of favor due to the inherent complications of its harvest2-5. Commonly used alternates for autologous bone graft (ABG) include, but are not limited to allograft, demineralized bone matrix (DBM), ceramics, and recombinant human bone morphogenetic protein (rhBMP). There are advantages and limitations of ABG and its substitutes which influence a surgeon to select a particular graft in different settings of spinal fusion6,7. However, one major drawback common to all ABG substitutes is that neither of them possess all three properties essential for bone fusion. With the advent of stem cell technology and its emergence into clinical practice, one such product has been made available for spinal fusion, i.e cellular bone allograft matrix (CBM). CBM is allogenic bone graft containing viable mesenchymal stem cells (MSCs) and/or osteogenic cells, and currently these account
for more than 17% of all bone grafts being used8. The model of MSCs with an osteo-conductive carrier has been proven in a number of animal studies9-24 and clinical trials25-37. Presumably so, as all three properties (osteoconduction, osteoinduction and osteogenesis) essential for bone fusion are present in this hybrid. Five products that are commercially available at present, include; Osteocel Plus (NuVasive, San Diego, CA, USA)38, Trinity Evolution (Orthofix, Lewisville, TX, USA)39, Cellentra Viable Cell Bone Matrix (VCBM) (Biomet, Warsaw, IN, USA)40, AlloStem (AlloSource, Centennial, CO, USA)41, and ViviGen (LifeNet Health, Virginia Beach, VA and DePuy Synthes Spine, Raynham, MA, USA)42. A comparative analysis of technical specifications has been given in Table 1. (Partly adapted from Skovrlj et al.8). Whereas four of these products attribute their efficacy to MSCs and osteoprogenitor cells, ViviGen has viable osteoblasts, osteocytes and bone lining cells. From in-vitro studies, they claim that these cells work faster than MSCs as they are already in a primed state for bone formation43. Orthofix released Trinity Elite (Orthofix, Lewisville, TX, USA) in 2013, a third generation allograft with viable cells and claim to have 100,000 MSCs out of a minimum total of 500,000 cells/cc44. Out of the limited data on clinical use of CBMs, Osteocel plus
has probably been evaluated the most. Kerr EJ 3rd et al25, in their retrospective review of 52 patients reported solid arthrodesis in 92.3% cases of multiple lumbar interbody fusion procedures using Osteocel plus as fusion substrate. In another retrospective review of 26 patients to determine the role of Osteocal plus in minimally invasive transforaminal lumbar interbody fusion (MITLIF), a fusion rate of 92.3% at 12 months follow up was found28. Tohmeh AG et al27 found 90.2% fusion of 61 XLIF levels at 12 months in their prospective trial using Osteocel plus. Eastlack RK et al29 also reported 92% fusion at 24 months with Osteocel plus and PEEK cage in single level ACDF and concluded that it is a reasonable alternate to other bone graft substitutes. In a non-industry sponsored study by McAnany et al37, a retrospective review of matched cohorts (n=57) was done evaluating the use of Osteocel plus as graft substitute against ABG as control in ACDF. They found a lower (insignificant) fusion rate with Osteocel plus as compared to control (87.7% vs 94.7%). A limitation of this study was that surgeries using Osteocel plus were done at a different institution than control group. All the above studies did not report any graft related adverse events. Vanichkachorn J et al36 assessed the clinical and radiological outcomes of 31 patients undergoing single level ACDF using Trinity
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Evolution (TE) as graft substitute. They found a 93.5% fusion rate at 12 months, and even in high risk groups 85 to 100% fusion rates were present. Out of all adverse events,
More clinical trials evaluating the safety and efficacy of CBMs are underway, results of which are currently not available45-48.
support their use in spine fusion. Furthermore, there are differences in the source, age of donor, harvest, processing, and MSC concentration of these products. These differenc-
Table 1. Comparative analysis among five commercially available CBMs Product
Osteocel Plus38
Trinity Evolution39
Cellentra VCBM40
AlloStem41
ViviGen42
Manufacturer
Nuvasive, Inc.
Orthofix
Biomet
AlloSource
LifeNet Health (represented by Depuy Synthes Spine)
Source of MSCs
Cadaver bone
Cadaver bone
Cadaver bone
Cadaver adipose tissue
Cadaver bone
Average donor age at harvest (y)
18-44
30
n/a
50
Cut off age 60 – Men 50 - Women
Time to processing after donor’s death (h)
≤72
≤72
≤72
n/a
≤48
Total cells/cc (Cryopreserved product)
3 Million
≥250,000
≥250,000
66,255
≥16,000 viable cells, *post thaw
MSCs/cc MSC %
n/a 68
≥1000 n/a
n/a n/a
66,255 100
*Does not claim efficacy due to MSCs. Has viable osteoblasts, osteocytes and bone lining cells.
Shelf life (mo)
60
60
18
60
6 (at local hospital or surgery center)
Recommended time to implantation after thaw (h)
≤6
≤2
≤4
n/a
≤2
Osteoconductive carrier
Cancellous bone chips
Demineralized bone
Cancellous bone matrix
Demineralized bone
Cortical cancellous chips and Demineralized bone
Osteoinductive cytokines
Naturally occurring in bone
Naturally occurring in bone
BMP-2, 4, Naturally occurring in bone 7; VEGF; TGF-b; PDGF; IGF1; FGF
Naturally occurring in bone
Cost/cc (approximate)
$460
$540
$620
n/a
they reported five that could possibly be attributed to TE. Two were related to unresolved pain, two to numbness and one related to posterior neck pain. Subsequently two resolved and three were present intermittently. 4
$540
Skovrlj B et al8 published a review article critically evaluating the technical specifications, data supporting use, FDA regulations, cost and pitfalls of five commercially available CBMs and concluded that although these appear to be safe, there is not enough evidence on efficacy to
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es have been shown to influence the activity and survivability of MSCs in a number of studies17,49-55, hence will serve as a potential pitfall for surgeons in selecting a particular product for use. A comparative study evaluating all these products in a single spinal fusion model will
establish any difference in efficacy and safety profile among these commercially available CBMs. Given the immense development of biologics in the field of spinal surgery, from a surgeon’s point of view there still remain unanswered questions regarding the use of CBMs. Foremost are efficacy and safety. Studies till now have shown promising results and no adverse events (definitely attributable to CBMs) have been reported. These products have bypassed the FDA premarket review as they claim to meet all FDA criteria under section 36, 21 CFR Part 12718. Unfortunately, products that take years or even decades to develop must go through a similar protracted clinical phase before they establish their position conclusively. What is needed for CBMs also, is to establish safety and efficacy in all settings of spinal fusion by way of non-industry sponsored, well designed randomized controlled trials. Only years and years of positive outcomes data will support the industry’s “lofty” claims. Another important aspect amidst this changing economy of health care is cost. Companies that are investing millions of dollars in developing and bringing such products to the market will want to sell them at a premium price. The cost for these products is similar to, or more than other graft substrates8. With current fusion techniques there is still a 10-15 % pseudoarthrosis rate56, presumably the direct and indirect costs involved with revisions is huge. If CBMs can significantly decrease pseudoarthosis rate (especially in multi-level cases), the total financial burden associated with spinal fusion can be cut substantially. Appropriate cost-utility and benefit analysis will eventually
establish whether these products reduce morbidity and societal cost associated with spinal fusion. Only responsible use and honest reporting of data from all clinical trials will provide an unbiased evaluation of use, and safety profile. What we definitely do not want, is to get carried away by the industry driven momentum and come at a controversial BMP “déjà vu”. Cellular bone matrix has the potential to be an ideal bone graft substitute, but only time will give us the answer we are looking for. References
1. Rajaee SS, Bae HW, Kanim LE, Delamarter RB. Spinal fusion in the United States: analysis of trends from 1998 to 2008. Spine (Phila Pa 1976). 2012 Jan 1;37(1):67-76. 2. Arrington ED, Smith WJ, Chambers HG, et al. Complications of iliac crest bone graft harvesting. Clin Orthop Relat Res 1996;326: 300–9. 3. Banwart JC, Asher MA, Hassanein RS. Iliac crest bone graft harvest donor site morbidity. A statistical evaluation. Spine 1995;20: 1055–60. 4. Summers BN, Eistein SM. Donor site pain from the ileum: a complication of lumbar spine fusion. J Bone Joint Surg Br 1989;71: 677–80. 5. Howard JM, Glassman SD, Carreon LY. Posterior iliac crest pain after posterolateral fusion with or without iliac crest graft harvest. Spine J 2011;11:534–7. 6. Kannan A, Dodwad SN, Hsu WK. Biologics in spine arthrodesis. J Spinal Disord Tech. 2015 Jun;28(5):163-70. 7. Fischer CR, Cassilly R, Cantor W, Edusei E, Hammouri Q, Errico T. A systematic review of comparative studies on bone graft alternatives for common spine fusion procedures. Eur Spine J. 2013 Jun;22(6):1423-35. 8. Skovrlj B, Guzman JZ, Al Maaieh M, Cho SK, Iatridis JC, Qureshi SA. Cellular bone matrices: viable stem cell-containing bone graft substitutes. Spine J. 2014 Nov 1;14(11):276372. 9. Cinotti G, Patti AM, Vulcano A, Della Rocca C, Polveroni G, Giannicola G, Postacchini F. Experimental posterolateral spinal fusion with porous ceramics and mesenchymal stem cells. J Bone Joint Surg Br. 2004 Jan;86(1):135-42. 10. Cui Q, Ming Xiao Z, Balian G, Wang GJ. Comparison of lumbar spine fusion using mixed and cloned marrow cells. Spine (Phila Pa 1976). 2001 Nov 1;26(21):2305-10. 11. Curylo LJ, Johnstone B, Petersilge CA, Janicki JA, Yoo JU. Augmentation of spinal arthrodesis with autologous bone marrow in a rabbit posterolateral spine fusion model. Spine (Phila Pa 1976). 1999 Mar 1;24(5):434-8; discussion 438-9. 12. Goldschlager T, Rosenfeld JV, Ghosh P, Itescu S, Blecher C, McLean C, Jenkin G.
Cervical interbody fusion is enhanced by allogeneic mesenchymal precursor cells in an ovine model. Spine (Phila Pa 1976). 2011 Apr 15;36(8):615-23. 13. Gupta MC, Theerajunyaporn T, Maitra S, Schmidt MB, Holy CE, Kadiyala S, Bruder SP. Efficacy of mesenchymal stem cell enriched grafts in an ovine posterolateral lumbar spine model. Spine (Phila Pa 1976). 2007 Apr 1;32(7):720-6; discussion 727. 14. Huang JW, Lin SS, Chen LH, Liu SJ, Niu CC, Yuan LJ, Wu CC, Chen WJ. The use of fluorescence-labeled mesenchymal stem cells in poly(lactide-co glycolide)/hydroxyapatite/ collagen hybrid graft as a bone substitute for posterolateral spinal fusion. J Trauma. 2011 Jun;70(6):1495-502. 15. Kai T, Shao-ging G, Geng-ting D. In vivo evaluation of bone marrow stromal-derived osteoblasts-porous calcium phosphate ceramic composites as bone graft substitute for lumbar intervertebral spinal fusion. Spine (Phila Pa 1976). 2003;28:1653–8. 16. Lopez MJ, McIntosh KR, Spencer ND, et al. Acceleration of spinal fusion using syngeneic and allogeneic adult adipose derived stem cells in a rat model. J Orthop Res. 2009;27:366–373. 17. Minamide A, Yoshida M, Kawakami M, et al. The use of cultured bone marrow cells in type I collagen gel and porous hydroxyapatite for posterolateral lumbar spine fusion. Spine (Phila Pa 1976). 2005;30:1134–1138. 18. Miyazaki M, Zuk PA, Zou J, et al. Comparison of human mesenchymal stem cells derived from adipose tissue and bone marrow for ex vivo gene therapy in rat spinal fusion model. Spine (Phila Pa 1976). 2008;33:863–9. 19. Muschler GF, Matsukura Y, Nitto H, Boehm CA, Valdevit AD, Kambic HE, Davros WJ, Easley KA, Powell KA. Selective retention of bone marrow-derived cells to enhance spinal fusion. Clin Orthop Relat Res. 2005 Mar;(432):242-51. 20. Nakajima T, Iizuka H, Tsutsumi S, Kayakabe M, Takagishi K. Evaluation of posterolateral spinal fusion using mesenchymal stem cells: differences with or without osteogenic differentiation. Spine (Phila Pa 1976). 2007;32:2432–2436. 21. Shamsul BS, Tan KK, Chen HC, Aminuddin BS, Ruszymah BH. Posterolateral spinal fusion with ostegenesis induced BMSC seeded TCP/HA in a sheep model. Tissue Cell. 2014 Apr;46(2):152-8. 22. Wang T, Dang G, Guo Z, Yang M. Evaluation of autologous bone marrow mesenchymal stem cell-calcium phosphate ceramic composite for lumbar fusion in rhesus monkey interbody fusion model. Tissue Eng 2005;11:1159–1167. 23. Wheeler DL, Fredericks DC, Dryer RF, Bae HW. Allogeneic mesenchymal precursor cells (MPCs) combined with an osteoconductive scaffold to promote lumbar interbody spine fusion in an ovine model. Spine J. 2016 Mar;16(3):389-99. 24. Wheeler DL, Lane JM, Seim HB 3rd, Puttlitz CM, Itescu S, Turner AS. Allogeneic mesenchymal progenitor cells for posterolateral lumbar spine fusion in sheep. Spine J. 2014 Mar 1;14(3):435-44. 25. Kerr EJ, Jawahar A, Wooten T, Kay S, Cavanaugh DA, Nunley PD. The use of
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osteo-conductive stem-cells allograft in lumbar interbody fusion procedures: an alternative to recombinant human bone morphogenetic protein. J Surg Orthop Adv 2011;20:193–7. 26. Johnson RG. Bone marrow concentrate with allograft equivalent to autograft in lumbar fusions. Spine (Phila Pa 1976). 2014 Apr 20;39(9):695-700. 27. Tohmeh AG, Watson B, Tohmeh M, Zielinski XJ. Allograft cellular bone matrix in extreme lateral interbody fusion: preliminary radiographic and clinical outcomes. ScientificWorld Journal 2012;ID263637. 28. Ammerman JM, Libricz J, Ammerman MD. The role of Osteocel Plus as fusion substrate in minimally invasive instrumented transforaminal lumbar interbody fusion. Clin Neurol Neurosurg 2013;115:991–4. 29. Eastlack RK, Garfin SR, Brown CR, Meyer SC. Osteocel Plus cellular allograft in anterior cervical discectomy and fusion: evaluation of clinical and radiographic outcomes from a prospective multicenter study. Spine (Phila Pa 1976). 2014 Oct 15;39(22):E1331-7. 30. Gan Y, Dai K, Zhang P, Tang T, Zhu Z, Lu J. The clinical use of enriched bone marrow stem cells combined with porous beta-tricalcium phosphate in posterior spinal fusion. Biomaterials. 2008 Oct;29(29):3973-82. 31. Bansal S, Chauhan V, Sharma S, et al. Evaluation of hydroxyapatite and beta-tricalcium phosphate mixed with bone marrow aspirate as a bone graft substitute for posterolateral spinal fusion. Indian J Orthop 2009;43:234–9. 32. Niu CC, Tsai TT, Fu TS, et al. A comparison of posterolateral lumbar fusion comparing autograft, autogenous laminectomy bone with bone marrow aspirate, and calcium sulphate with bone marrow aspirate. Spine 2009;34:2715–9. 33. Kitchel SH. A preliminary comparative study of radiographic results using mineralized collagen and bone marrow aspirate versus autologous bone in the same patients undergoing posterior lumbar interbody fusion with instrumented posterolateral fusion. Spine J 2006;6:405–12. 34. Hart R, Komzák M, Okál F, Náhlík D, Jajtner P, Puskeiler M. Allograft alone versus allograft with bone marrow concentrate for the healing of the instrumented posterolateral lumbar fusion. Spine J. 2014 Jul 1;14(7):1318-24. 35. Ajiboye RM, Hamamoto JT, Eckardt MA, Wang JC. Clinical and radiographic outcomes of concentrated bone marrow aspirate with allograft and demineralized bone matrix for posterolateral and interbody lumbar fusion in elderly patients. Eur Spine J. 2015 Nov;24(11):2567-72. 36. Vanichkachorn J, Peppers T, Bullard D, Stanley SK, Linovitz RJ, Ryaby JT. A prospective clinical and radiographic 12-month outcome study of patients undergoing single-level anterior cervical discectomy and fusion for symptomatic cervical degenerative disc disease utilizing a novel viable allogeneic, cancellous, bone matrix (trinity evolution™) with a comparison to historical controls. Eur Spine J. 2016 Feb 5. 37. McAnany SJ, Ahn J, Elboghdady IM, Marquez-Lara A, Ashraf N, Svovrlj B, Overley SC, Singh K, Qureshi SA. Mesenchymal stem
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cell allograft as a fusion adjunct in one- and two-level anterior cervical discectomy and fusion: a matched cohort analysis. Spine J. 2016 Feb;16(2):163-7. 38. NuVasive. Bone Grafting Solutions. Osteocel Plus. Available at: http://www.nuvasive. com/patient-solutions/bone-grafting. 39. Orthofix. Trinity Evolution. Available at: http://web.orthofix.com/Products/Pages/ Trinity-Evolution.aspx. 40. Biomet. Cellentra VCBM (viable bone cell matrix). Available at: http://www.biomet.com/ wps/portal/internet/Biomet/HealthcareProfessionals/products/spine/osteobiologics/. 41. Allosource. AlloStem Cellular Bone Allograft. Available at: http://www.allosource. org/products/allostem-cellular-bone-allograft/. 42. DePuy Synthes. ViviGen Cellular Bone Matrix. Available at: https://www.depuysynthes.com/hcp/spine/products/qs/vivigen-cellular-bone-matrix. 43. Data on file. LifeNet Health. 44. Trinity Elite. Technical Monograph. Available at: http://web.orthofix.com/Products/Products/Trinity%20ELITE/Trinity-ELITE-Technical-Brief.pdf. 45. U.S National Institutes of Health. Cellentra Viable Cell Bone Matrix (VCBM) Anterior Cervical Discectomy and Fusion Outcomes Study (VCBM/MaxAn). Available at: https:// clinicaltrials.gov/ct2/show/NCT02182843. 46. U.S National Institutes of Health. Osteocel® Plus in Posterior Lumbar Interbody Fusion (PLIF). Available at: https://clinicaltrials.gov/ ct2/show/study/NCT00941980. 47. U.S National Institutes of Health. Osteocel® Plus in Anterior Lumbar Interbody Fusion (ALIF). Available at: https://clinicaltrials.gov/ ct2/show/NCT00948831. 48. U.S National Institutes of Health. Safety and Efficacy Study of NeoFuse in Subjects Undergoing Multi-Level Anterior Cervical Discectomy and Fusion. Available at: https:// clinicaltrials.gov/ct2/show/NCT01106417. 49. Hernigou P, Mathieu G, Poignard A, Manicom O, Beaujean F, Rouard H. Percutaneous autologous bone-marrow grafting for nonunions. Surgical technique. J Bone Joint Surg Am. 2006 Sep;88 Suppl 1 Pt 2:322-7. 50. Cuomo AV, Virk M, Petrigliano F, Morgan EF, Lieberman JR. Mesenchymal stem cell concentration and bone repair: potential pitfalls from bench to bedside. J Bone Joint Surg Am. 2009 May;91(5):1073-83. 51. Klingemann H, Matzilevich D, Marchand J. Mesenchymal Stem Cells - Sources and Clinical Applications. Transfus Med Hemother. 2008;35(4):272-277. 52. Ragni E, Viganò M, Parazzi V, Montemurro T, Montelatici E, Lavazza C, Budelli S, Vecchini A, Rebulla P, Giordano R, Lazzari L. Adipogenic potential in human mesenchymal stem cells strictly depends on adult or foetal tissue harvest. Int J Biochem Cell Biol. 2013 Nov;45(11):2456-66. 53. Grabowski G, Robertson RN. Bone allograft with mesenchymal stem cells: A critical review of the literature. Hard Tissue 2013 Mar 22;2(2):20. 54. Muschler GF, Nitto H, Boehm CA, Easley KA. Age- and gender-related changes in the cellularity of human bone marrow and the prev-
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alence of osteoblastic progenitors. J Orthop Res. 2001 Jan;19(1):117-25. 55. Wu W, Niklason L, Steinbacher DM. The effect of age on human adipose-derived stem cells. Plast Reconstr Surg. 2013 Jan;131(1):2737. 56. Hustedt JW, Blizzard DJ. The controversy surrounding bone morphogenetic proteins in the spine: a review of current research. Yale J Biol Med. 2014 Dec 12;87(4):549-61.
CERTIFICATION
Update on ABNS Exams
Vincent Traynelis, MD Professor of Neurosurgery A. Watson Armour III & Sarah Armour Presidential Chair Department of Neurosurgery Rush University Medical Center Chicago, IL The American Board of Neurological Surgery (ABNS) administers three separate and distinct examinations. Two must be successfully completed to obtain Board Certification and the third is necessary to maintain certification. The ABNS has worked to improve these examinations in a number of areas over the last several years. The purpose of this communication is to provide a broad review and update on each. The reader is referred to the Bylaws, Rules and Regulations which are posted on the ABNS website (www.abns.org) for all of the important granular details associated with these examinations and Board Certification. The Primary Exam The first examination is the Primary Examination or what is also commonly referred to as the written exam. This must be completed while in residency. It is administered once a year at the training programs. The Primary Examination effort was directed by Mark Hadley for the last several years and now Carl Heilman will assume responsibility for overseeing this
endeavor. Dr. Hadley produced an examination consisting of properly constructed and vetted questions spanning the spectrum of Neuroanatomy, Neuroscience, Neuropathology, Neuroimaging, Clinical Neurology, Fundamental Clinical Skills/ Critical Care, Core Competencies, and Neurosurgery. He was the catalyst for the recent transition from a written book to an online format and provided the oversight for the change to occur in a smooth fashion. This new format allows for the expansion of visual data which are so important to our specialty. The exam consists of 375 questions and that number will not change in the immediate future. What will change is that the number of Neuroscience and Clinical Neurology questions will decrease and the number of Critical Care and Neurosurgery questions will increase reflecting what is more relevant to the practice of Neurosurgery. There is also a desire to link the Primary examination to the SNS (Society for Neurological Surgery) Matrix. Currently it is about 75% aligned with this tool. Alterations and additions to the Matrix and modifications of the test should improve the congruency of the two with time with the idea that the examinee could utilize the Matrix as an accurate and focused study guide. The Oral Examination The oral examination is the last event in the initial Certification process, which begins with neuro-
surgical residency in an ACGME accredited program and passage of the Primary Examination for credit. Alan Cohen directed this effort for a number of years and now it is in the hands of Doug Kondziolka. The oral examination explores knowledge and judgment in clinical neurosurgical practice after an applicant has been an independent practitioner. The oral examination is accomplished in a series of face-to-face examinations involving the applicant, current and former Directors of the Board, and/ or guest examiners. The applicant is presented a series of clinical vignettes, using clinical descriptions, radiographs, computerized images, anatomical models and/or diagrams. The examiners grade the applicant on specific tasks including diagnostic skills, surgical decision making and complication management. The oral examination covers a broad range of neurosurgery practice: (a) intracranial neurosurgery; (b) complex spine surgery; and (c) other areas, i.e., neurology, neurocritical care and pediatric surgery, etc. Candidates must pass each of the three subjects of the examination in order to achieve an overall passing score. The oral examination is administered twice a year. Commencing in the Spring of 2017, the ABNS certifying oral examination will still consist of three sessions but they will be modified as follows: Session one will test the candidate’s fund of knowledge and competency on general neurosurgery. Session two will test the candidate’s competen-
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cy on elements of his/her focused surgical practice. Each candidate will indicate their choice prior to the examination from a list of focused practice selections. Session three will be a case based examination consisting of 5-8 cases selected from the 150 cases submitted by the candidate during the credentialing process. Each candidate will prepare a PowerPoint using an ABNS slide template for each case that contains the clinical history, physical examination, key imaging, diagnosis and management, surgical coding, early result and follow-up. The candidate must pass all three sessions to become ABNS certified.
modules a Diplomate may choose to take ( i.e. General Neurosurgery, Spine, etc.) Two years ago the test administration changed so that a Diplomate could take it at any site with internet access and the test was “open book”. The surveys following these changes revealed an overwhelming amount of enthusiasm for the new format. One point in the surveys that was not so positive was the relevancy of the questions. The ABNS has responded to that important feedback and going forward the examination will change.
Part III of MOC (the examination) will be a novel adaptive learning tool beginning in 2017 in an effort The ABNS believes that evaluatto make it educationally beneficial, ing a candidate’s practice and the more relevant and efficient. The cases performed by the individual primary goal for changing the is a more appropriate means of 2017 Part III MOC is to provide assessing competency. It should updated “evidence based” core lessen the stress of preparation for neurological surgery knowledge in the candidate and still allow the an educationally effective format. ABNS to judge the quality of care The other goal is to augment our delivered so the value of CertificaDiplomates’ safe practice of neution is maintained and the public is rological surgery through a tool protected. that engages the participant in an active learning process using a web Maintenance of Certification (MOC) based format. The prior “all or Examination nothing 200+ question exam” will MOC was directed by Vincent be replaced with an instrument that Traynelis for the last 5 years and it will promote engagement, safety, is now overseen by Sander Connol- and learning at the Diplomates own ly. Currently each Diplomate must speed, without pressure. The web successfully complete this exam based learning tool can be mastered once every ten years. There are in the comfort of the Diplomates’ several different focused practice home or office over a favorable time
8
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period. The learning tool will consist of updated knowledge that has evolved since an ABNS Diplomate’s last certification so the experience will be far shorter, more relevant and focused than the prior MOC exam. The platform the ABNS will use is designed by the same innovative company which delivers millions of American Heart Association exams such as Basic Life Support (BLS). Thus, the format will be familiar and easy to use for our Diplomates. Questions will focus on evidence based neurological surgery principles important for all ABNS certified neurological surgeons. Unlike most standard exams, immediate feedback to each question will be provided to the Diplomate by this novel adaptive learning tool. References with links and/or articles will be provided so the learner can effectively absorb the information and correct their answers with a new question, signifying they have mastered the concept. The emphasis is on learning new evidence based neurological surgery concepts in an educationally robust, stress free environment. It is expected that each Diplomate completing Part 3 of MOC will do so successfully and learn throughout the process.
NEW TECHNOLOGIES
Adopting New Technologies & Techniques Seth K Williams, MD Surgical techniques are always evolving and inevitably as a surgeon’s career progresses, he or she will adopt procedures that they did not learn in their residency or fellowship. Ask any surgeon who is more than 10 years into their career to list the procedures they now perform that they were not exposed to in training. As new techniques and technologies become available, it can be difficult to decide which ones to adopt and when to wait. Four different scenarios are described here, with details of the main barriers to adoption and strategies to assess and implement the new technique or technology when appropriate.
performed percutaneously, and using the microscope and working through a tubular retractor. In this manner the surgeon never feels lost and minimal additional risk is conveyed to the patient as the surgeon can seamlessly move back to the familiar open procedure. As long as the surgeon also does a few cadaver courses and visits a surgeon to observe the procedure and perhaps is even proctored during their early experience, it would be expected that they could safely adopt this technique. And there is always the bailout of converting to an open procedure without excessive harm to the patient provided they understand and accept this as a possibility.
Perhaps the easiest scenario involves modification of an existing technique with the same end result. One example is a laparoscopic appendectomy. If the surgeon is struggling, this procedure can easily be converted to open, with the same end result for the patient, removal of their appendix. They may have a couple of extra scars but as long as the patient has been prepared for this possibility, then there should not be excessive risk to the patient. The MIS TLIF is an example in the spine, whereby the decompression and fusion and instrumentation are quite similar to the open procedure, but through a different surgical corridor. This technique can be learned by doing an open TLIF in the conventional manner, but placing the screws fluoroscopically or image guided in the same fashion as would be
The direct lateral fusion is a different beast, and is an example of the second scenario. The anatomical approach is totally unfamiliar to most spine surgeons, unless they have experience doing open multi-level anterior fusions as with adult deformity, but even then the approach is different. If the surgeon is struggling, the only bailout is to abort the procedure and convert to a posterior approach. This isn’t the end of the world as long as the patient is prepared for this possibility, but it is far from ideal. With this type of procedural scenario, adoption is most easily achieved when another person at your institution can teach you and is available to help in your early experiences. However, this is not common, and attending a few cadaver courses and doing a site visitation may not completely
prepare you to safely perform a direct lateral fusion. A surgeon faces some difficult choices in the early adoption phase. Do you involve a general or vascular surgeon and start with a larger incision, and slowly progress to smaller incisions and independence? Or just go for it after proper preparation? Either way, diligent training and careful patient selection are key to safely adopting this procedure, you don’t want L4/5 with a high iliac crest to be your first case.
“When is it worthwhile to shell out a million dollars for a CT scanner and an image guidance platform? How do you evaluate the role this technology will have in your practice in the long run?” Cervical (ACDA) and lumbar (LDA) disk arthoplasty are examples of the third type of new technology and technique adoption. In this case the surgical approach is exactly the same as with the existing technique, ACDF or ALIF, and as long as you are diligent and prepared, implantation is relatively straightforward. The patient carries all the risk here. We cannot tell the patient how this implant will be functioning in 20 or 30 years, we just do not know. Here the difficulty lays not so much in the technical aspect of adopting
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this new technology, instead it is the decision of when to start to offer this technique and how to counsel the patient and help them make a decision. How do you decide when a new device is safe to start using? What kind of evidence do we need? We can’t all wait for 10 and 20-year results because then nothing new would happen. Some surgeons must be early adopters, and other than the legal risk of doing a procedure that later is a flop, the patient carries the vast majority of the risk burden. Metal on metal hips exploded in popularity and turned out to be a bit of a disaster. It would have been much better to take a slower approach. Pedicle screws had early issues and legal problems but have turned out to be safe and effective, so early adoption ultimately was not a problem. With cervical and lumbar disk arthroplasty there has been quite a divergence in utilization because of differences in outcomes. With this type of new technology, the surgeon should be convinced that the technique is safe and effective and then the patient must be heavily involved in the decision process. Ideally the patient who is otherwise an ideal candidate for the new technique should be educated by the surgeon, do research on their own, and then come back to the surgeon and demonstrate a full understanding of the options and make the definitive decision that they want the new technique.
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The final category of new technique adoption involves cost. CT navigation is a good example. The same approach and technique for pedicle screw placement or brain tumor excision can be employed with CT navigation as with the conventional technique. Careful patient selection for early cases will allow the surgeon to use and learn the technology without totally relying on it, and then as comfort is gained, the surgeon can increasingly depend on it. The issue here is the cost. When is it worthwhile to shell out a million dollars for a CT scanner and an image guidance platform? How do you evaluate the role this technology will have in your practice in the long run? This is a difficult question to answer and perhaps involves trialing the technology on sawbones models and then cadavers, speaking with other surgeons about their experiences with the technology, researching the literature to determine of the new technology improves outcomes or safety, visiting a surgeon and observing, and ideally trialing the equipment before committing. We have and will all be faced with these scenarios as we progress through our careers. In one described scenario, it is mainly the surgeon time and energy commitment to learning the technique (MIS TLIF). With some scenarios the novel technical aspect of the
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surgery is the difficult part (direct lateral fusion), in others it is the unknown long-term consequences of the procedure (ACDA), and in others there is a high startup cost (CT navigation). Sometimes we may be pioneers or early adopters, but most of the time we will take a measured approach to introducing new techniques and technologies into our practice. There is no formula for how best to do this, but it should be helpful to have an understanding of the main barriers to adoption and some of the strategies to employ when considering implementation.
IMPROVEMENT
What It Means to be a “Spine Center of Excellence” Choll Kim, M.D., Ph.D.
gather information far above that Excellence is defined as a state of which is required for the everyday being “superior; imminently good.” care of our patients. Today, most To be excellent, one must show surgeons are too busy to withstand how they are better than anoththat incremental burden on their er. In general, this requires some clinical practice. Ultimately, this system of measurement. Mealeads to poor surgeon participation suring outcomes is commonplace and low enrollment. To successin everyday life. For example, the fully develop a large outcomes avid golfer uses the handicap score registry, the data collection requireto measure one’s skill relative to ments must be minimized. another. Similarly, baseball uses the ERA (earned run average) to compare pitching effectiveness. Thus, excellent golfers and baseball “The field of spine pitchers would simply be those surgery currently enjoys players who have the best scores. It is only logical that excellent suran unprecedented degree geons would be identified as those of agreement on one having the best treatment scores. Unfortunately, the human condition is far more complex than golf or baseball. The diversity of human disease and its clinical manifestations is vast. The task of organizing disease states and measuring treatment outcomes can be overwhelming. But, it is not impossible. The variability and complexity of spinal disorders can be addressed by gathering information in sufficiently large numbers such that patients can be grouped into “buckets”. This can be readily accomplished if a large number of surgeons participate in an outcomes registry. Therein lies the rub. In our efforts to collect meaningful data, we have burdened ourselves with a task that is not compatible with everyday practice. We often fall into the trap of attempting to
measures such as length of stay, 30-day readmission rate, 90-day re-operation rate, and major complication rates, constitute a core set of outcomes measures that can be collected easily in a busy clinical practice. This large registry dataset would serve as a starting point from which excellence can be built. Ongoing data collection would allow for rapid assessment of new treatment strategies, whether that is diagnostic, technical, and/or organizational. Only in this manner can a program truly distinguish itself as a center of excellence.
issue: clinical outcomes measures.”
As in most things, timing is everything. The field of spine surgery currently enjoys an unprecedented degree of agreement on one issue: clinical outcomes measures. It is now expected that clinical studies report the Visual Analog Scale (VAS) for pain, a system-specific functional outcomes score such as the Oswestry Disability Index, and a general health survey such as the SF-12 or EQ-5D. While other scoring systems are numerous, these baseline measures are in widespread use. These outcomes measures are completed by the patient via a simple questionnaire. These, along with basic treatment-specific Vertebral Columns • Spring 2017
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