Incidence of spondylolisthesis in ambulatory cerebral palsy patients

We prospectively studied 50 consecutive ambulatory cerebral palsy (CP) patients to determine the incidence of isthmic spondylolisthesis. In addition, we examined the relationship of hip flexion contractures to development of spondylolisthesis and low back pain. Three patients who had undergone previous spine operation were eliminated from the study group. Of the remaining 47 patients, one patient (2%) demonstrated an asymptomatic grade I spondylolisthesis. Another patient (2%) demonstrated spondylolysis without spondylolisthesis. Only six patients reported occasional low back pain. Pain did not correlate with increasing age, increasing hip flexion contracture, or decreasing sacrofemoral angle. The incidence of spondylolisthesis in this group of ambulatory CP patients with hip flexion contractures is similar to that in the general population. Hip flexion contractures did not predispose the group to spondylolisthesis or low back pain. Periodic screening of asymptomatic ambulatory CP patients for spondylolisthesis is not recommended.