OBJECTIVE: the objective of this study was to identify the occurrence of adjacent disc syndrome secondary to intervertebral fusion in the cervical segment, and the predictors of outcome. METHODS: the medical records and imaging studies of 209 patients undergoing surgical treatment of cervical degenerative disease, with 169 cases treated through anterior approach and 40 cases through the posterior approach, at the HC-FMUSP from March 1993 to January 2007. Clinical evaluation was quantified by the scale of Japanese Orthopaedic Association (JOA), with an average follow-up of 80 months. The radiological analysis was based on the criteria of instability by White and Panjabi in all cases. The degeneration was measured by the scale of Kellgren before and after surgery. RESULTS: overall, the syndrome of adjacent disc was diagnosed in 30 cases (17.75%), with a mean time interval of incidence of 28.5 months after the merger, or 2.9 cases per year. There was an increase in degenerative changes in X-rays at levels adjacent to anterior fusion in 41.42% and 52.5% for the posterior without fusion, evaluated by the scale of Kellgren, the degeneration rate of 6.7% per annum, with no correlation with clinical changes. CONCLUSIONS: changes in physiological sagittal alignment of the spine and their severity predispose to the development of the syndrome. There was no incidence of the syndrome in cases of pseudoarthrosis or methacrylate, therefore, where there was a merger. The use of decompression and fusion, anterior, is associated with the possibility of developing a new framework for myeloradiculopathy in the postoperative period. Merger at a level that involve the fifth or sixth cervical vertebra, fixation with plates and pre-existing radiographic evidence of disc degeneration adjacent were factors of high risk for its emergence.
Spinal diseases; Spinal fusion; Syndrome; Intervertebral disc
