title: Prevalence of adjacent segment disc degeneration in patients undergoing anterior cervical discectomy and fusion based on pre-operative MRI findings.
abstract: Anterior cervical discectomy and fusion (ACDF) is a widely accepted surgical treatment for symptomatic cervical spondylosis. Some patients develop symptomatic adjacent segment degeneration, occasionally requiring further treatment. The cause and prevalence of adjacent segment degeneration and disease is unclear at present. Proponents for motion preserving surgery such as disc arthroplasty argue that this technique may decrease the "strain" on adjacent discs and thus decrease the incidence of symptomatic adjacent segment degeneration. The purpose of this study was to assess the pre-operative prevalence of adjacent segment degeneration in patients undergoing ACDF. A database review of three surgeons' practice was carried out to identify patients who had undergone a one- or two-level ACDF for degenerative disc disease. Patients were excluded if they were operated on for recent trauma, had an inflammatory arthropathy (for example, rheumatoid arthritis), or had previous spine surgery. The pre-operative MRI of each patient was reviewed and graded using a standardised methodology. One hundred and six patient MRI studies were reviewed. All patients showed some evidence of intervertebral disc degeneration adjacent to the planned operative segment(s). Increased severity of disc degeneration was associated with increased age and operative level, but was not associated with sagittal alignment. Disc degeneration was more common at levels adjacent to the surgical level than at non-adjacent segments, and was more severe at the superior adjacent level compared with the inferior adjacent level. These findings support the theory that adjacent segment degeneration following ACDF is due in part to the natural history of cervical spondylosis.
authors.affiliation: Department of Orthopaedics, Southern Health, Dandenong Hospital, 135 David Street, Dandenong, VIC 3175, Australia. Electronic address: krislundine@gmail.com.
authors.forename: Kristopher M
authors.initials: KM
authors.lastname: Lundine
authors.affiliation: Department of Neurosurgery, Austin Hospital and Cabrini Hospital, Melbourne, VIC, Australia.
authors.forename: Gavin
authors.initials: G
authors.lastname: Davis
authors.affiliation: Department of Neurosurgery, Austin Hospital and Cabrini Hospital, Melbourne, VIC, Australia.
authors.forename: Myron
authors.initials: M
authors.lastname: Rogers
authors.affiliation: Monash Department of Clinical Epidemiology, Cabrini Hospital, Department of Epidemiology and Preventive Medicine, Melbourne, VIC, Australia.
authors.forename: Margaret
authors.initials: M
authors.lastname: Staples
authors.affiliation: Department of Spinal Surgery, Austin Hospital, Melbourne, VIC, Australia.
authors.forename: Gerald
authors.initials: G
authors.lastname: Quan
mesh_terms: D000328:Adult; D000368:Aged; D002574:Cervical Vertebrae / Q000473:pathology / Q000601:surgery; D017586:Diskectomy / Q000009:adverse effects*; D005260:Female; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000209:etiology* / Q000473:pathology / Q000601:surgery*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000453:epidemiology*; D015995:Prevalence; D012307:Risk Factors; D013123:Spinal Fusion / Q000009:adverse effects*; D055815:Young Adult
keywords: Adjacent segment disease; Anterior cervical fusion; Cervical disc disease; Disc degeneration; Magnetic resonance imaging