[Clinical and radiological surveys of lumbar spondylolysis in young soccer players].

Four thousand eighty one young boy soccer players ranging from age 7 to 12 were surveyed with a hope to establish the specific causative factors and the preventive measures for spondylolysis. Four hundred ninety six (12%) out of these players were found to have lumbago. Two hundred forty seven out of these boys with lumbago received X-ray examinations on which 122 were found to have lumbar lesions. These lesions included spondylolysis, concave vertebral endplates and narrowed disc, the incidence of which were 30.8%, 21.1%, and 8.1%, respectively. Spondylolysis occurred most commonly at L5 and was classified into fissure type (56 cases) and pseudoarthrosis type (20 cases). The occurrence of spondylolysis was related well to the duration of the training time per week. On X-ray examinations, spondylolysis was found to be correlated closely with trapezoid deformity at L5 and increased lumbar lordosis. Thirty patients (71%) out of 42 with fissure type showed solid healing of their pars defect as a result of conservative therapy. The results of the present study indicated that young soccer players should limit their training time to 1.5 hours per day and to 3 days per week in order to prevent spondylolysis.