There are contradictory reports regarding patellar position in the Osgood-Schlatter disease. We present a prospective statistical study of 17 patients with Osgood-Schlatter disease and 12 adolescents without anterior knee pain. The Caton-Deschamps index was assessed on strictly the lateral radiograph of the knee. The findings indicate a strong association between Osgood-Schlatter disease and patella alta. This increase in patellar height would require an increase in the force needed from the quadriceps to achieve full extension. This mechanism could be responsible for the apophyseal lesion.