Outcome of transpedicular screw fixation in surgical treatment of isthmic spondylolisthesis in adults

ABSTRACT

Isthmic lumbar spondylolisthesis is a complex orthopedic and neurosurgical problem. Between 1995 and 2000, twenty three adult patients with symptomatic isthmic lumbar spondylolisthesis who failed to respond to conservative treatment were operated upon by posterolateral fusion and transpedicular screw fixation combined with a variety of decompressive procedures; namely, decompressive laminectomy, excision of fibrocartilaginous pseudoarthrotic mass and/or foraminotomy when indicated by preoperative imaging studies and operative findings. The surgical results were evaluated at an average follow up of 21 months. Nineteen patients had favorable clinical outcome. Solid fusion was evident in 20 patients. Individual clinical symptoms showed variable degrees of improvement. Low back pain improved at variable degrees in 91.3%, sciatica improved in 89%, intermittent claudications improved in 75% and neurological deficits improved in 87.5%. Loosening of screws was the commonest complication encountered occurring in 2 patients. In this study, posterolateral fusion combined with an appropriate decompressive procedure and instrumentation by transpedicular screws without reduction for isthmic spondylolisthesis in adults resulted in a high fusion rate and favorable clinical outcome: