61 jumper's knees (fifty patients) are studied. Predisposing factors, clinical and radiographyc manifestacions are relationated in order to obtain a more effective treatment. 50% showed radiographyc disturbances of the patellar vertex, 25% had hight patella and 20% condromalacia was associated. Surgery was performed in 10 knees, and conservative treatment in the rest. Poor results and relapses arose in later treated cases. Prevention and early treatment are very important in these cases.