"Temporary" Short Segment Fixation in Treating Adolescent Lumbar Spondylolysis.

Abstract

We have introduced a new operation for isthmic spondylolysis in adolescents and evaluated its clinical efficacy. A total of 30 adolescent patients with isthmic spondylolysis and chronic low back pain underwent "temporary" short-segmental pedicle screw combined with transverse device fixation and isthmic bone graft repair treatment. Radiograph and computed tomography images were evaluated during regular follow-up examinations to confirm successful bone graft fusion, after which the fixation was removed. Lumbar magnetic resonance imaging was performed before and 1 year after fixation surgery and 1 year after fixation removal. Modic and Pfirrmann grading standards were used to observe the effect of "temporary" fixation on the corresponding vertebral endplate and intervertebral disc. All 30 patients had complete follow-up data available at 2 years postoperatively. The low back pain symptoms had disappeared completely, and radiographs and computed tomography showed that the isthmus in all patients had achieved bony fusion. With removal of the internal fixation, motion of the fixed segment recovered. "Temporary" rigid internal fixation did not increase the corresponding vertebral endplate or intervertebral disc degeneration. "Temporary" short-segmental pedicle screw combined with transverse device fixation is a simple and effective method for adolescent isthmic spondylolysis with rigid internal fixation and accelerated bone graft fusion.