Examination of locomotor system of elementary school students using diagnostic ultrasound system and lower limb flexibility assessment: toward early detection of Osgood-Schlatter disease during growth period

This study aimed to evaluate a musculoskeletal screening method for elementary school students using ultrasound and lower limb flexibility assessments, with the goal of early detection of Osgood-Schlatter disease during the growth period. A total of 143 boys in the fourth to sixth grades of elementary school from a single prefecture underwent musculoskeletal screening between November 2021 and February 2023. Using a diagnostic ultrasound device, the tibial tuberosity was observed, and its developmental stage was classified based on Ehrenborg’s four-stage classification (Ehrenborg G and Lagergren C. 1961. Acta Chir Scand 121: 315–327). The presence of Osgood-Schlatter disease was determined based on the presence of irregularities in the ultrasound image. Lower limb flexibility was assessed quantitatively using finger-floor distance (FFD) and heel-hip distance (HHD). The cartilaginous stage (C stage) was the most common developmental stage observed. Osgood-Schlatter disease was identified in eight children (5.6%) and was found only in the epiphyseal (E) and bony (B) stages (p = 0.004, φ = 0.308). HHD was significantly greater in the Osgood-Schlatter group (p = 0.040, r = 0.680). In some children without knee pain or tenderness, irregularities in the tibial tuberosity were detected on ultrasound imaging, suggesting that ultrasound imaging may be useful for the early detection of asymptomatic lesions. This screening approach, which combines ultrasound examination and flexibility assessment, is expected to serve as a novel method for the early detection and prevention of musculoskeletal disorders in children during their growth period. Further large-scale studies and continued investigation into methods for assessing flexibility in growing children are warranted.