BACKGROUND: Imaging shows that many patients with lumbar degenerative disease after internal fixation obtain sufficient neurological decompression and good bone graft fusion, but they can not satisfy with clinical effect because of residual low back pain, so there may exist other factor which affect the clinical effect.
OBJECTIVE: To investigate the effect of the lumbar flexibility and facet joint degeneration on clinical effect of lumbar internal fixation.
METHODS: Totally 120 cases underwent lumbar internal fixation of L4 and L5. Lumbar lordosis angle at extension and flexion position was measured preoperatively as the lumbar flexibility index. Facet joint angle of L3,4 was measured and the degeneration of facet joint was graded. Oswestry score was obtained before and after one year operation and improvement rate was calculated. The effect of the lumbar flexibility and facet joint degeneration on the improvement rate after operation was analyzed.
RESULTS AND CONCLUSION: Lumbar flexibility was positively correlated with the improvement rate. Patients with severe degeneration of the facet joint and with asymmetry facet joint angle both have a bad improvement rate. Lumbar flexibility, lumbar facet joint degeneration and facet joint symmetry are the important factors which influence the outcome of lumbar internal fixation.