Post Market Data Collection Protocol to Evaluate the Performance of the Synergy Disc

Inclusion Criteria: * Age 21 or above at the time of the surgery. * Have had (retrospective cohort) or the decision has been made to have (prospective cohort) the Synergy Disc implanted * Skeletally mature patients for reconstruction of the disc from C3-C7 following a single or multiple level discectomy for intractable radiculopathy * Intractable radiculopathy and/or myelopathy with at least one of the following producing symptomatic nerve root and/or spinal cord compression: * herniated disc and/or osteophyte formation * Symptomatic nerve root and/or spinal cord compression documented by patient history (arm or neck pain and/or neurologic deficit) and imaging (CT, MRI, x-rays, etc.) * Failed a minimum of 6 weeks conservative treatment * Written informed consent given by subject. Exclusion Criteria: * Exclusion Criteria: All answers must be NO to be eligible for the study. * Moderate to advanced spondylosis * Diagnosis of osteoporosis * Active systemic infection or infection at the operative site * Pregnancy * Marked cervical instability on lateral, coronal, or flexion/extension radiographs * Cervical spine condition other than symptomatic cervical disc disease requiring surgical treatment at the involved level * Severe pathology of the facet joints of the involved vertebral bodies * Previous diagnosis of osteopenia or osteomalacia * More than one immobile vertebral level between C1 and T1 from any cause * Morbid obesity * Vulnerable person (pregnant patients, emergency cases, children, prisoners and people without mental capacity)