A series of 190 patients (91 men, 99 women) with the fifth lumbar spondylolysis were examined clinically and radiographically on two occasions. one with only lysis and the another with lysis and olisthesis. The symptomatical differences were not particularly evident between the two groups subjectively and objectively. The lumbar index and the S-H angle were shown to be prognostic values for the development of vertebral slipping.
