A Retrospective Study to Examine the Effect of CMF Stimulation on Primary ACDF Patients

Inclusion Criteria * Male or Female aged 18-75 years. * Primary anterior cervical discectomy fusion (ACDF) and required two level spinal fusion or were active smokers and required either single or two level spinal fusion. * Pain VAS score \>5 and/or extreme weakness at target operative level(s). * At least one post operative clinical outcome assessment (VAS pain/ NDI/OC score) at each follow up interval. * Completed 6 month follow up visit or time to fusion assessment, whichever is sooner. Exclusion Criteria * Treated with a bone growth stimulator device other than the SpinalogicTM CMF device. * Previous cervical vertebrae fusion surgery at any level (posterior or anterior approach) * Systemic administration of any type of corticosteroid, antineoplastic, immune- stimulating or immunosuppressive agents within 30 days of primary ACDF surgery and/or within 12 weeks post-operatively. * Active history of systemic malignancy at pre-operative assessment or during 12- month follow up period. * Untreated malignant neoplasm(s) or underwent radiotherapy or chemotherapy at pre- operative assessment or during 12-month follow up period. * Implanted with cardiac pacemaker or implantable cardioverter defibrillator at pre- operative assessment or during 12-month follow up period. * Pregnant at pre-operative assessment or during 12-month follow up period. * Mental or physical condition that would interfere with post-treatment assessments and/or care (e.g., neuromuscular disease, psychiatric disease, * Paraplegia, quadriplegia, etc.) at pre-operative assessment or during 12-month follow up period. * Prescribed non-steroidal anti-inflammatory, calcium channel blockers and/or diphosphonate therapy within 12-weeks of surgery period. * Prescribed bone morphogenic protein (BMP) during 12-month follow up period. * Implanted with a Titanium cage during the primary ACDF that precludes an outcome determination via plain radiographs. * Osseous or ligamentous spinal trauma at pre-operative assessment or during 12- month follow up period. * Paget's disease at pre-operative assessment or during 12-month follow up period. * Absence of X-ray fusion assessment documentation at 6 months follow-up visit.