1. 1. 3rd Cervical Disc Arthroplasty (CDA) Practical Course Speaker: F Adamo, DVM, DECVN Instructors: F Adamo, DVM, DECVN R Kroll, DACVIM (Neurology) C Giovannella, DACVIM (Neurology)
2. 2. Course Objectives Mastering the CDA technique Avoid common mistakes Enable you to perform CDA independently on your first clinical case Additional supervision is available upon request
3. 3. Morning session: 1st hour: History of CDA & description of the instrumentation Recent clinical data Video of the technique in a clinical case 2nd hour: Dr. Kroll lecture Frequently Asked Questions Practice CDA on canine plastic cervical model Afternoon session: 3 hrs Practice CDA on canine cadavers 1 hrs Discussion & Certification Cocktail/Appetizers Course schedule
4. 4. Registry Approved Continuing Education (RACE) RACE approved for 5 hrs of CE To receive the CE- credit hrs at the end of this course you have to fill out: Participation Evaluation form 14 post-test questions
5. 5. Padfolio content: Schedule Printed copy of the CDA surgical technique FAQ questions + answers Test: 14 questions for RACE Evaluation form CE credit certificate Other information: - dropbox - wobblersyndrome.com CDA course
6. 6. Hallmarq Shawn Miller Perioptix Urban Skyler Sontec Instruments Angus & Dennis Sponsors
7. 7. Goals: Preserve motion after neural decompression while providing distraction and stability Potentials: May prevent domino lesions Advantages: Treatment of multiples adjacent & not adjacent spaces CDA Indications: Disc Associated Wobbler Syndrome
8. 8. Phase 1. DESIGN Madison, WI 2003 Phase 2. IN VITRO BIOMECHANICAL STUDY Adamo, Kobayashi et al. Vet Surgery 2007 4 Groups of 6 cervical spines (C5-C6) a) Arthroplasty, b) Ventral Slot, c) Pins+PMMA fixation, d) and normal spine The artificial disc was better able to mimic the behavior of intact spine compared with ventral slot and Pin+PMMA groups. History
9. 9. Phase 3. Pilot clinical study in 2 client-owned dogs mmmmm with DAWS Titanium alloy Results Follow up to 3 years post-op Died for unrelated neurological diseases MRI re-check 2 years post-op No evidence of compression at the treated and adjacent sites Conclusions Cervical arthroplasty was well tolerated and provided excellent outcome in both dogs Warranted further study: Large number of patients Longer follow-up Adamo JAVMA, 239(6), 2011
10. 10. Cervical Disc Arthroplasty using the Adamo Spinal Disc in 33 dogs affected by Disc Associated Wobbler Syndrome at Single and Multiple Levels. In preparation to be Submitted to JAVMA
11. 11. Study Authors F Adamo, DECVN East Bay Vet Specialists CA R Da Costa, DACVIM (Neurology) The Ohio State University OH R Kroll, DACVIM (Neurology) VCA Northwest Vet Specialists OR C Giovannella, DACVIM (Neurology) Gulf Cost Vet Neurology/Neurosurgery TX M Podell, DACVIM (Neurology) Chicago Vet Specialty Group IL P Brofman, DACVIM (Neurology) Veterinary Specialty Care, SC A Multi-Center Prospective Study
12. 12. To evaluate the immediate postoperative recovery, the short-, intermediate- and long term follow-up of dogs with one level and multi-level disc- associated-wobbler-syndrome (DAWS) treated with cervical disc arthroplasty (CDA). Objective
13. 13. Material & Methods Implant: similar to that described in the preliminary study, but with several modifications. Adamo JAVMA, 239(6), 2011 Adamo Spinal Disc 2nd & 3rd Gen. Internal surfaces Concavity is titanium Convexity is PEEK (PolyEther Ether Ketone) Thermoplastic polymer Decreases friction Prevent metallic debris from a metal to metal joint Acts as a ball and socket Patent: US 8,496,707 B2
14. 14. External surface Convex To resemble natural concavity of vertebral end plates To prevent implant migration Implant
15. 15. External surface Concentric grooves To provide grip To allow bone in-growth into the implant 2nd Generation Treated with Dual Acid Etch Bath to promotes bone/implant incorporation 3rd Generation Treated with Hydroxyapatite to better promotes bone/implant incorporation Implant
16. 16. 1st generation 2nd generation - Ball in PEEK - Thinner size 3rd generation - Ball in PEEK - Thinner size - Hydroxyapatite Coating Implant Design Modification 4rd generation - Ball in PEEK - Finally thinner size - Hydroxyapatite Coating - Additional wider & taller sizes 8.5 mm 8.3 mm
17. 17. Implant Design Modification 7 different disc sizes Set of dedicated tools + WL1 & WL2
18. 18. Threaded pins to hold the assembled prosthesis Dedicated tools
19. 19. Thick end Parallel channels to hold the assembled prosthesis during implantation Thin end Slotted to remove the pins after implantation Barrel Holder Double function Dedicated tools
20. 20. Sizing Probe Resemble at each end the shape of either mthe S, M, or W disc size To probe/test the disc space during nburring, before final disc implantation Dedicated tools
21. 21. Small burr To clean end-plates and begin creating concavity Large burr matches the external disc convexity To facilitate implant accommodation by the disc space Large burrSmall burr Two dedicated burrs Dedicated tools
22. 22. 20 degree angle attachment for the Surgairtome To facilitate working at an angle parallel to the disc space during burring Particularly useful at C6-C7 (and C7-T1 !!) Dedicated tools
23. 23. Caspar Cervical Distractor To maintain vertebral distraction during implantation To allow visualization through the disc space to the dorsal longitudinal ligament Dedicated tools
24. 24. Disc space prepared for the implant Vertebral end plate Dorsal Long. Lig.
25. 25. Sample population: First 33 clients-owned dogs w/ over 2 mo. history of DAWS Diagnosed by MRI or CT myelo Weight over 23 kg, but one (12.2 Kg) Neurologically and radiologically evaluated Prior to surgery Shortly after surgery within 24 hrs At 2 wks & 3, 6, 12 & 24 mo. after surgery Including Criteria
26. 26. Total = 50 disc sites treated Single, two and three level lesions Neurological Assessment Grade 0 to 6 De Decker, et al. JAVMA 2012; 240:848857 C3 C4 C5 C6 Material and Methods 0: No apparent neurological deficits 1: Cervical hyperesthesia w/o deficits 2:: Hind limb ataxia w/o visible paresis 3: Hind limb ataxia with paresis & no appreciable forelimb ataxia 4:: Ambulatory tetraparesis: broad- based ataxia hind limbs & choppy gait forelimbs (two engine gait) 5:: Non-ambulatory tetraparesis: able to stand/walk few steps before collapse 6: Tetraplegia
27. 27. Optimal Implant well centered in the disc space on lateral & VD views Sub-optimal Off midline on VD Inadequate Not seated in center of the disc space on lateral view Inadequate position Implant Position
28. 28. Relative Distraction ratio (RDR): Ratio between post-op and pre-op width at the treated space Adequate / Ideal* RDR > 1.7 and < 2 * Equivalent to a distraction of 2-3 mm Under distraction RDR < 1.7 Over-distraction RDR > 2 C7C6 C5 C7 C6 C5 Pre-op Post-op Distraction
29. 29. Ventro-flexion Dorsi-flexion Neutral Mobility Distance between dorsal and ventral edge of the 2 faces of the implant in neutral and stressed views Present Not detectable
30. 30. 2 years post-op when possible As needed, in the event of recurrence of clinical signs MRI re-evaluation
31. 31. Results
32. 32. Breeds: 17 Doberman Pinchers (50%) 3 Dalmatians 2 Labrador 2 Bernese Mountain dog 1 Standard Poodle 1 Weimeraner 1 Boxer 1 Greyhound 5 Mix Sex: 21 M; 12 F Age: 4 - 13 y; Mean 8.3 y 27% over 10 y old
33. 33. Single level: 19 dogs C6-C7 (13 dogs) C5-C6 (5 dogs) C3C4 (1 dog) Two levels: 10 dogs C5-C6 & C6-C7 (8 dogs) C4-C5 & C5-C6 (1 dog) C3-C4 & C5-C6 (1 dog) Lesion Localization Three levels: 3 dogs C3-C4, C5-C6 & C6-C7 (2 dogs) C2-C3, C5-C6 & C6-C7 (1 dog) TOTAL: 50 Spaces treated C6 C7 C3 C4 C5 C6 C3 C4 C5 C6
34. 34. Inadequate position Immediate Post-op Radiographs Implant position: Optimal (40/48 sites) Sub-optimal (7/48 sites) Off midline on VD Inadequate (1/48 sites) Improper technique Excessive burring of caudal endplate immediate subsidence
35. 35. Caudal subsidence Distraction: Over-distraction (15/50 sites) Mostly with 1st generation (thicker) implant Adequate distraction (34/50 sites) Mostly with 2nd & 3rd generation (thinner) implant Under-distraction: (1/50 sites) Improper technique Excessive burring of caudal endplate immediate subsidence Immediate Post-op Radiographs
36. 36. Distraction lost compared to immediate post-op, but maintained when compared to pre-op All sites More pronounced with 1st generation (thicker) implant Less pronounced with 2nd and 3rd generation (thinner) implant Subsidence Distraction lost compared to pre-op 7/50 sites (14%) Ventral Osteophytes 2 sites in one dog Serial Radiographic Assessment
37. 37. Mobility Present: at 2 wks post-op in 88% in 24 dogs examined at 6 mo post-op in 23% in 14 dogs examined In 7 dogs where dynamic study was performed immediately after surgery: mobility although expected was not detectable in 5/10 of the treated spaces No Implant migration No Implant infection Serial Radiographic Assessment Ventro-flexion Dorsi--flexion
38. 38. 6 weeks post-op (1 dog) Improper technique C6-C7 Declined after surgery Dorsal compression at C5-C6 due to loss of distraction Improved with single dorsal decompression 7 mo. post-op (1 dog) New osteophytes or heterotopic ossification Clinical status unchanged Dog 2 C5-C6 C5 C6 C7 T2 sagittal MRI C5-C6 6 wks post surg C5-C6 pre surgery MRI Re-assessment: 6 dogs
39. 39. 20-24 mo. post-op (4 dogs) 2 dogs: No signs of disc degeneration or compression at treated and adjacent sites 2 dogs: New osteophites or Heterotopic Ossification. 1st and 2nd generation implant C6 C7* MRI Re-assessment C3-C4 C5-C6 In all dogs the implant didnt affect the spinal cord visibility
40. 40. Post-op recovery time Immediate in all dogs Neurological status unchanged compared to pre-op status in all dogs Post-op hospitalization time * 5 dogs: Discharged same day 25 dogs: 1- 3 days 2 dogs: 4 - 5 days Based on the severity of the neurological status pre-surgery Clinical Assessment
41. 41. Follow-up: Mean 24 mo, (range 2 wks - 42 mo) 22 dogs still alive 11 dogs deceased 8 for non-neurological diseases 3 euthanasia: insufficient improvement or complications Patient Outcome 91% have shown improvement of at least 1+ neurological grade Satisfactory to Excellent: 30 dogs Unsatisfactory: 1 dog Poor: 2 dogs No Domino lesions during the observation period Better: mild and short duration of signs on presentation Worse: chronic non-ambulatory paraparesis + extensor rigidity of front legs not resolving under general anesthesia Clinical Assessment
42. 42. Patch: 6 y old MN Dalmatian 6 mo ambulatory tetraparesis worsening 2 mo prior to presentation
43. 43. Sonny: 8 y old MN Doberman 1y ambulatory tetraparesis, acute tetraplegic 7 months post-op
44. 44. Complications and Poor Outcome
45. 45. Complications Vertebral fissure fracture during distraction: 2 dogs Improper Caspar pins placement +/- excessive distraction with Caspar Distractor Did not affect the outcome Immediate subsidence: 1 dog Improper technique: over-burring. Surgical revision with dorsal laminectomy Regained improvement Subsidence: 7/50 disc spaces Too thick and too narrow discs Except for 1 dog, did not affect the outcome Improper technique
46. 46. Complications Vertebral Axial Compression fracture: 1 dog Nikkie Sheltie Mix, F, 12.4 y old, 29 lb = 12.2 kg History 4 years ambulatory ataxia, 6 month prior to referral non ambulatory tetraparesis with extensor rigidity all 4 legs, not resolving under anesthesia Overdistraction RDR 3.2 (normal > 1.7 and < 2) 2 weeks post-op Pre-op Immediate Post-op C5 C6 C7
47. 47. Complications Nikkie 2 weeks post-op Declined to non-ambulatory tetraparesis Intense cervical pain Radiography: Suspected Axial compression fracture C6 Ventral implant migration Euthanasia - no histopathology What went wrong? Dogs size too small: 13.2 Kg Over-distraction Thinner discs sizes currently not available for these dogs size Weak geriatric vertebrae (osteoporosis)!? Combination of the above Poor patient selection 2 weeks post-op 2 weeks post-op C5 C6 C7
48. 48. Poor Outcome 2 dogs Chow Mix, F, 13.5 y old Doby, M, 12 y old History 8-14 months progressive non ambulatory tetraparesis Severe extensor rigidity all 4 legs, not resolving under anesthesia Outcome: Dog 1 (Chow): Euthanized 8 mo. after surgery d/t insufficient improvement Dog 2 (Doby): Neuro score improved only from 6 to 5 What went wrong? Neurological signs too advanced / severe Irreversible spinal cord damage Poor patient selection Pierce Simon
49. 49. Limitations of CDA: Dogs size Patient under 23 Kg are not good candidates for CDA Underlying vertebral diseases Weaker bone in geriatric dogs In humans usually bone density test Not good candidate for CDA Prolonged history of non-ambulatory tetraparesis Severe extensor rigidity of front legs not resolving under general anesthesia Overall: too severe / advanced neurological signs Clinical Relevance
50. 50. Advantages of CDA Less invasive than traditional surgeries Rapid post-surgical recovery Can be performed on a out-patient basis Treatment of multiple lesions at adjacent or non-adjacent sites Prophylactically for Incipient lesions May prevent Domino lesions C7 C6 C5
51. 51. Spinal cord decompression & dynamic stabilization Immediate relief of radicular pain and vascular compression at the intervertebral foramina Enable MRI re-assessment for complications for long term re-assessment of domino lesions Other Benefits C6 C7*
52. 52. Disadvantages Limitations Concurrent Dorsal spinal compression The possible decrease of distraction over time may exacerbate the dorsal compression If concurrent dorsal compression, it might be necessary to combine CDA along with removal of the dorsal compression at the affected site
53. 53. Conclusions CDA using this prosthesis appears to be safe and effective Suitable for medium and large breed dogs Rapid post-surgical recovery Ideal for treating multiple levels Not technically difficult and easy to master May prevent Domino Lesions May improve pet-owner willingness to pursue a surgical option
54. 54. Conclusions CDA is very promising for the treatment of DAWS. Case selection , Early Intervention and Correct execution of the surgical technique may be critical factors for the outcome Case selection is King, technique is the Prince Dr. Zelman column: number 6 of the most commonly cited attributes of a great surgeon
55. 55. Current Updates
56. 56. HA coating Calcium and phosphorous complex Promote maturation of collagen fibers surrounding titanium implants and support osteoconduction To improve bone/implant incorporation Thinner implants & additional wider and taller sizes S1, M1, M2, WT1, WT2, WL1 & WL2 To avoid over-distraction, To increase contact surface implant/vertebral endplate to decrease the degree of subsidence 4rd Generation Adamo Spinal Disc
57. 57. CDA Surgery kit
58. 58. Cervical Disc Prostheses Sizes Selection Indication
59. 59. Disc size selection Pre-operative MRI measurement Final assessment during surgery
60. 60. CDA Surgery video - Clinical case Inserire video surgical technique
61. 61. 3rd CDA Course 1. Questions ?? 2. Break 10 min. 1. Dr. Kroll Lecture 1. Frequently Asked Questions Dr. Adamo 2. Practice on spine specimens Dr. Adamo, Dr. Kroll, Dr. Giovannella 3. Lunch 4. Practice on cadavers
62. 62. Dr. Robert Kroll CDA Case Selection
63. 63. Cervical Disc Arthroplasty (CDA)k Frequently Asked Questions & Answers
64. 64. a. Discectomy with deep cleaning of the end plates from the annulus b. Minor burring to accommodate the disc implant 1. Will I be performing a discectomy or a ventral slot?
65. 65. Just enough to create space for the disc implant. a. The small burr is used for the initial burring and to create enough space to insert the large burr. b. The large burr is used for the final cleaning of the end- plate, and to create enough space to accommodate the disc in the discectomy site c. Mild exposure of the cancellous bone in the center area of the caudal vertebral endplate is acceptable and often needed. Small burr Large burr C5C6 2. How much do I have to burr?
66. 66. C6 C7 C5 C6 C7 Burring of the caudal vertebral end-plate C7C6 C7 C6
67. 67. Parallel to each other but at about a 30-degree angle away from the midline and away from the side on which the surgeon is standing. 3. Which is the best position to place the Caspar distractor pins?
68. 68. Placing the pins too far from the affected disc space may cause vertebral fracture during distraction. Place the pins toward the center or caudal third in the cranial vertebral body, and toward the center or cranial third of the caudal vertebral body 4. How can I prevent vertebral fracture during Caspar distraction? X X
69. 69. Place the pin toward the center of the vertebral body that will be receiving the discectomies and the disc implants at both ends 5. In the event that two adjacent sites have to be treated at the same time, what is the best pin placement?
70. 70. Until it becomes difficult to distract any more! 6. How much do I have to distract?
71. 71. The widest and tallest disc size possible that fits in the discectomy site. The increased area of contact between the implant and the vertebral end-plate, may decrease the degree of subsidence. It is best to select the disc that fits firmly in the disc space but that doesnt cause excessive vertebral distraction; too much distraction may increase subsidence. 7. Which disc size is best to use?
72. 72. Before closure, bone wax can be packed on the ventral edges of each vertebra facing the external surface of the implant. 8. How can I prevent ventral bridging spondylosis and tissue ingrowth between the two articulating faces of the implant?
73. 73. A lateral, VD, and dynamic views in dorsi-flexion and ventro- flexion This to have a baseline to assess distraction and mobility on the following serial post-operative radiographs 9. Which views should be included in the immediate post-operative radiographs? NEUTRAL VENTRO-FLEXION V-D DORSI-FLEXION
74. 74. 2 weeks, 3, 6, 12 and 24 month follow-up 10. To evaluate distraction and mobility when is recommended to perform serial post-op radiographs? NEUTRAL VENTRO-FLEXION DORSI-FLEXION V-D 9 mo. Post-op: - Maintained Mobility, - Maintained Distraction, - No Subsidence
75. 75. Fracture of the vertebral body Weak bone in old dogs Excessive distraction (disc too thick) Using this implant in dogs < 23kg Less likely to affect the outcome: Osteophytes and Heterotopic Ossifications Vertebral ankylosis Spondylarthrosis Loss of distraction and/or mobility Minor Subsidence 11. Which one is the most serious complication of CDA that may affect the clinical outcome? 2 weeks post-op 2 weeks post-op C5 C6 C7
76. 76. Not less than 23 kg 12. What is the recommended minimum patient weight for the application of this prosthesis?
77. 77. Leash walk until 3 month radiographic re-check Full activity after 6 months radiographic re-check 3 mo. post-op 6 mo. post-op 13. For how long is activity restriction recommended?
78. 78. Questions
79. 79. CDA Practice on spine specimens Objective: Familiarization with the technique and instruments (discs not treated with HA)
80. 80. Wet-lab CDA- guidelines Implants used in this lab are not HA coated 10 cadavers 5 surgery stations x 2 times 3 participants in 3 stations 2 participants in 2 stations Each participant will practice 2 CDA surgeries The instructor will first show CDA at C3-4 Your disc spaces to practice are C4-5; C5-6 & C6-7 Name yourself #1, #2 and #3 On the first set cadavers: #1 C4-5; #2 C5-6; #3 C6-7 On the second set of cadavers #1 C6-7; #2 C4-5; #3 C5-6 Post-op Radiographs Discussion: Remember on the 2nd cadaver: your dog number and the disc space where you placed the implant
81. 81. Questions?
82. 82. Thanks for your attention Wet-lab session CDA
83. 83. Post - Surgery - Radiographs Discussion
84. 84. How to place the order Allison Hsia: Events Assistant AVT
85. 85. How to place the order Special offer for attending the Course: Total value of surgery kit: $ 15,260 Discount for attending the course: - $ 1,200 2 additional discs sizes of $1,500 value: Complimentary Additional 10% discount for placing the order within 30 days: - $ 1,406 --------------------------------------------------------------------- New Total $ 12,654 Cost of Shipment not included
86. 86. Opportunity to promote and differentiate your practice with an innovative surgical technique Average surgery cost (surg. + anesthesia):$ 3,500 Mark up implant (x1.5 or x2): $ 1,000 - 1,500 Total cost of surgery: $ 4,500 - 5,000 Number of surgeries to recup. the investment: 3 Cost Analysis
87. 87. How to place the order For Full discount: place order within 30 days from today. Payment options: Payment in full today and take the surgery kit home Deposit $500 minimum and remaining balance before shipment Guarantees one of the limited available surgery kits To assemble a new surgery kit it may take up to 3 month from the order. Order can also be placed by contacting: Preeti Zalavadia, pzal@appliedvt.com - Administrative Assistant of AVT.
88. 88. Certificates Participants of the very 1st CDA Course 2013
89. 89. Thank you for your participation and attention!