Ultrasound Analysis of Patellar Tendon Morphology in Runners, Cyclists, Triathletes, and Active Individuals

This study aimed to compare the patellar tendon (PT) morphology, specifically length, thickness, and cross-sectional area (CSA), among cyclists, runners, triathletes, and physically active individuals. Forty healthy participants, aged 18 to 45 (average age 30.3 years), were divided into four groups of 10 (cyclists, runners, triathletes, and physically active controls). Using a B-mode ultrasound system, PT measurements were taken: length and thickness at 5, 10, 15, and 20 mm along the tendon with a probe positioned parallel to the tendon, and CSA at 25%, 50%, and 75% of PT length with the probe positioned perpendicularly. Data analysis involved one-way ANOVA for PT length and two-way ANOVA (group vs. position) for thickness and CSA, followed by post-hoc Tukey tests, with significance set at p < 0.05. The results indicated that cyclists had significantly smaller PT thickness at all measured locations compared to triathletes (p = 0.001) and physically active individuals (p = 0.043), though no significant difference was observed compared to runners. No significant differences were found among the groups regarding PT length or CSA, and there were no significant interactions between local measurement positions. In conclusion, cyclists had consistently smaller PT thickness than triathletes and physically active individuals, but thickness was similar to that of runners. This finding suggests that PT thickness may vary based on sport-specific demands, with cyclists potentially experiencing different tendon adaptations. However, there were no differences in PT length or CSA among the groups.