Original Article: PDF OnlyThe Incidence of Spondylolysis and Spondylolisthesis in Nonambulatory PatientsROSENBERG, NORMAN J., MD*; BARGAR, WILLIAM L., MD‡; FRIEDMAN, BARRY, MD*Author Information *From the Department of Orthopaedic Surgery, Mount Sinai Hospital, Cleveland, Ohio ‡From Case Western Reserve University Hospitals, Cleveland Ohio Spine: January-February 1981 - Volume 6 - Issue 1 - p 35-38 Buy Abstract Radiographs were obtained of the lumbosacral spines of 143 patients that had never walked. The frequency of spondylolysis and spondylolisthesis was determined, as well as that of other spinal abnormalities. The average age of the patients was 27 years, with a range of 11 to 93 years. The underlying diagnoses responsible for the nonambulatory status varied, but cerebral palsy predominated. No case of spondylolysis or spondylolisthesis was detected, and when compared to the 5.8% incidence in the general population, this finding is significant at the P < 0.001 level. The incidences of spina bifida 8.4%) and of transitional vertebrae (10.9%) are similar to those found in the general population. Scoliosis was found in 49% and vertebral body height was increased in 32.9%. Degenerative changes occurred in only 2.8%. These results support the theory that spondylolysis and isthmic spondylolisthesis represent a fatigue fracture resulting from activities associated with ambulation. © Lippincott-Raven Publishers.