- Overall success rate – composite score. [ Time Frame: 18 months ]
To be considered an overall success, patients have to achieve all of the following: a ≥15 point improvement in their NDI scores, maintenance or improvement in their neurologic status, no serious adverse events related to the implant or surgical procedure, and no subsequent surgery or intervention that is classified as “failure.”
This is a prospective randomized comparative outcomes study, in which all subjects who fit the inclusion and exclusion criteria and who agreed to be part of the study will be randomized to either Allograft or Cohere polyetheretherketone (PEEK) fusion group and will be followed for approximately 12 months following surgery according to the standard-of-care.
Pain and function will be assessed using neck disability index (NDI), 36-Item Short Form Survey (SF-36), and Numeric Rating Scale (NRS). A trained study team member will record a standardized neurologic examination, including motor, sensory, and reflexes. Neurologic success is defined as maintenance or improvement of all 3 neurologic parameters (motor, sensory, and reflexes). The clinical results will also be assessed using the Japanese Orthopedic Association (JOA) scoring system for cervical myelopathy.
Flexion and extension radiographs will be obtained pre-operatively, at 6-months and 12-months after surgery. A CT scan will be obtained at 6 months, if fusion has occurred no CT is needed at 12 months, if fusion did not occur another computerized tomography (CT) scan will obtained at 12 months. From previous literature, successful fusion is defined as ≤2° of angular motion on lateral flexion and extension radiographs, the presence of bridging trabecular bone between the vertebrae being fused, and the absence of any radiolucent zones spanning more than 50% of the allograft surface. Two independent blinded radiologists will assess the radiographs. In the event of disagreement about fusion healing, a third independent reading will be obtained from a third radiologist.