[Lumbar spondylolysis and sports. The radiological findings and statistical considerations].

The authors report the results of the retrospective study of 473 cases of spondylolysis observed on 3,505 plain films of the lumbar spine performed on athletes with low-back pain, from 1962 to 1992. The analysis of the results showed that: a) the incidence of spondylolysis was higher in athletes (13.49%) than in the general population (4-7%); b) the incidence of spondylolysis was higher in the distal portion of the lumbar spine (in 81.40% of cases L5 was involved); c) in 52% of cases spondylolysis was associated with spondylolisthesis--the latter of grade 1 according to Meyerding's classification in 74.39% of cases; d) bilateral and single-segment forms prevailed; e) the incidence of spondylolysis differed in the various sports according to the specific mechanical stimulation involved.