Abstract:

Objective    To analyse the lumbar static and dynamic sagittal rotatable stability of patients with bilateral slipping prophase lumbar spondylolysis.   Methods    The lumbar X-ray of 55 patients with bilateral slipping prophase lumbar spondylolysis was analyzed. On the lateral X-ray radiography of  the lumbar spine under the conditions of  static and hyperflexion-hyperextension, the intervertebral disc angles of L4/5 or L5/S1 with spondylolysis were measured. The differences between the hyperflexion and hyperextension intervertebral disc angles were calculated. A randomized controlled study was performed between persons underwent physical check-ups and patients. the statistical analysis was performed.   Results    Intervertebral disc angles were not statistically different between patients with bilateral slipping prophase lumbar spondylolysis and persons underwent physical check-upson static and hyperextension lumbar lateral X-ray（P>0.05）. On lateral X-rayradiography under the condition of hyperflexion, the intervertebral disc angle was statistically different between them（P＜0.05）. The difference of intervertebral disc angle on lateral X-ray radiography under the conditions of hyperextension and hyperflexion was statistically significant（P＜0.05）. Conclusion   Dynamic sagittal rotatable instability exists on bilateral slipping prophase lumbar spondylolysis undergoing motion of flexion and extension. Surgical intervention needs to be provided as soon as possible

Key words: Lumbar spondylolysis, Slipping prophase, Lumbar instability