Direct repair of spondylolysis presenting after correction of adolescent idiopathic scoliosis

Abstract

Background context: Although spondylolysis is found in 6% of idiopathic scoliosis patients, very little was reported on management of pars defects in this group. These patients with painful spondylolysis are most eligible for direct repair of the defect rather than lumbosacral fusion in an attempt to save motion segments.

Purpose: The aim of this work was to analyze the clinical and radiologic outcome of pars repair in a group of adolescents who presented after surgical correction of their idiopathic scoliosis.

Study design: A prospective nonrandomized study.

Patient sample: Ten consecutive patients with spondylolysis presenting after an average of 3 months (range, 2-7 months) from correction of their idiopathic scoliosis with low back pain not responding to conservative therapy and interfering with everyday activities. The mean age at operation was 16 years (range, 14-19 years).

Outcome measures: Total blood loss, operative time, and hospital stay were recorded. Clinical outcome was assessed by the Oswestry Disability Index (ODI), visual analog scale (VAS), and Scoliosis Research Society (SRS)-22 questionnaire. Fusion of the pars interarticularis was assessed using plain, lateral, and oblique radiographs and a computed tomography (CT) scan.

Methods: The surgical technique consisted of thorough debridement of the defect, impacting the gap created with a tricortical iliac crest graft, and rigid fixation by either pedicle screws and a V-shaped rod (five patients) or a cable-screw construct (five patients).

Results: Patients were followed up for an average of 4.5 years (range, 2-7 years). Nine patients had a good-to-excellent result, returned to normal everyday life, and participated in sports when desired. The mean ODI, VAS, and SRS total scores were 11 (range, 0-34), 1.1 (range, 0-2), and 92 (range, 61-108), respectively. Follow-up radiographs and CT scans revealed healing of all defects in nine cases, no signs of disc degeneration in any, and no implant-related complications.

Conclusions: The results of direct repair of spondylolysis in idiopathic scoliosis patients were very satisfactory both clinically and radiologically. Direct repair appears to be a logical alternative to spinal fusion; lumbar spine mobility was preserved, and precocious motion segments were saved with a relatively simple operation.