ABSTRACT
Purpose: The purpose of this study was to determine the relationship between the flexibility of the quadriceps femoris and the period from onset of the Osgood-Schlatter disease. Subjects: 45 patients (66 lower limbs) with Osgood-Schlatter disease participated in this study. Methods: Subjects were classified into acute-phase group (pain occurred within one month, 23 subjects, 32 lower limbs) and chronic-phase group (pain occurred over one month, 22 subjects, 34 lower limbs). As a measure of muscle flexibility of the quadriceps femoris, Heel-Buttock distance (HBD) were measured in all participants. Results: The flexibility of the quadriceps femoris within the chronic-phase group was significantly reduced flexibility (10.2 ± 6.5 cm) than in acute-phase group (4.6 ± 5.9 cm; p < 0.001). Conclusion: Patients of the OSD, even if not found a decrease in muscle flexibility of the quadriceps femoris during the acute phase, may be decrease the flexibility as time passes. Prevent the worse symptoms of OSD, it would be effective to introduce stretching from acute phase irrespective reduced flexibility in the physical therapy treatment plan.