is the most reliable option for twolevel anterior cervical surgery Matthew Colman, MD Assistant Professor, Spine Surgery and Musculoskeletal Oncology Rush University Medical Center
Disclosures Medicrea: Consulting Depuy Synthes Spine: Consulting and Fellowship support Spinal Elements: Consulting AO Spine North America: Fellowship Support
: The Ideal Procedure for Cervical Radiculopathy and Myelopathy It works! Neurologic success: 89-98% NDI improvement: 28-31 points Overall health (SF36 improvement): 10-13 points VAS neck and arm improvement: 4-5 points
: The Ideal Procedure for Cervical Radiculopathy and Myelopathy It has low complication rates Dysphagia (up to 30-40% but most transient) Pseudarthrosis (wide range; 1/3 to 1/2 asymptomatic) Adjacent segment disease and degeneration (2.9% / yr, most likely when 5-7 are excluded)
: The Ideal Procedure for Cervical Radiculopathy and Myelopathy Stands the test of time Cost effective Versatile Instability Myelopathy Posterior element fractures Severe degenerative disease Systemic arthridities Deformity
What are the issues specific to two level? Multilevel disease is more likely to reflect underlying spondylotic process More levels = compounded pseudo risk More levels = lower ASD rates
The challengers Two-level cervical disc arthroplasty Compared to fusion: Improved Patient Reported Outcomes Preserves radiographic motion Less clinical ASD Less reoperation Mixed neurologic outcome
Inherent study bias Industry-surgeon relationship bias Study grants to institutions Personal relationships New technology
Inherent study bias Industry-surgeon relationship bias Study grants to institutions Personal relationships New technology Patient bias Euphoria
Inherent study bias Industry-surgeon relationship bias Study grants to institutions Personal relationships New technology Patient bias Euphoria Surgeon bias No clear protocols for revision Selection bias (fulfilling criteria for CDA may mean a different disease process)
The failure modes are different! MOBI-C 2-level IDE trial at 60 months CDA Pseudo ASD Rare persistent radiculopathy Motor vehicle accident?? poor attachment to bone (x2) dislodgement of device (x2) temporary paralysis postop hoarseness from device removal device malposition repositioned device during hematoma evacuation
Questions from the two-level CDA trials Cheng (Bryan Disc PRCT) Better VAS neck and arm, NDI Radcliff (MobiC 5 year independent review) Better NDI, SF12 Lanman (Prestige LP 6 year) Better NDI, neurologic success
Questions from the two-level CDA trials pseudo rate was high @ 14.3% (8.6% operative pseudo) 60% operative rate for radiographic pseudo Plain films only for fusion assessment Surgeon preference only driver of operative management
Questions from the two-level CDA trials ASD reoperation: Why no change when moving between the one and two level trials?
Questions from the two-level CDA trials Index level reoperation: Acceleration of risk for when moving between the one and two level trial +50% +30%
Long term uncertainty
Long term uncertainty
The challengers Hybrid Construct Prospective trial with 2 year F/u Better NDI improvement Better recovery of preop C2-7 motion Less inferior adjacent compensatory motion
Even if you believe the data, you have to get the inclusion criteria correct Aside from the standard inclusions. T-score > -1.5 One or less immobile vertebra between C1-7 Lack of radiographic facet disease Lack of Spondylosis No RA, autoimmune, reactive, or other undiagnosed systemic arthritis Even more difficult for two level disease! Vast majority of patients will be most appropriate for
Conclusion for two level disease Has predictable neurologic and patient-related outcomes Stands the test of time Versatile Complications and reoperations are straightforward and familiar to manage Vacant of myriad outcomes bias present with other devices, which may or may not be as great as we think
Thank You!