Association between patellar tendon-related pain and morphological abnormalities of the patellar tendon visualized using ultrasound imaging in middle school athletes

BACKGROUND/OBJECTIVE: To investigate whether morphological abnormalities of the patellar tendon, assessed using ultrasound imaging, are associated with patellar tendon-related pain in adolescent soccer players. METHODS: This cross-sectional observational study was conducted at a university and enrolled 140 middle school soccer players (280 knees). Pain assessment was conducted using the visual analog scale and tenderness. Physical function assessments were also conducted. Ultrasound imaging was used to evaluate the morphology of the patellar tendon. RESULTS: Data on a total of 211 knees were analyzed. Compared with non-painful knees, knees with patellar tendon-related pain exhibited significantly lower knee extension strength and a higher prevalence of hypoechoic and Doppler findings. The logistic regression analysis demonstrated a significant association between hypoechoic findings and patellar tendon-related pain (adjusted odds ratio = 10.65, 95% confidence interval: 3.65-31.88, p < 0.001), whereas no significant associations were observed for other morphological or physical function measures. CONCLUSION: Hypoechoic findings in the patellar tendon were significantly associated with patellar tendon-related pain in adolescent soccer players. These findings suggest that ultrasound imaging may be useful for identifying tendon characteristics that are associated with pain. However, longitudinal studies are needed to establish causal relationships.