Background: Patellar tendinopathy (PT) is a common sports-related injury that often recurs. Heavy Slow Resistance Training (HSR) and High-Dose Therapeutic Ultrasound (TUS) are commonly used to treat PT. However, there is a lack of research on the combined effectiveness of these treatments.
Methods: In this study, fifty-one college students aged 18 to 25, diagnosed with patellar tendinopathy using musculoskeletal ultrasound, were randomly assigned to three groups: a Combined HSR and high-dose TUS treatment group (n=17), an HSR training group (n=17), and a high-dose TUS treatment group (n=17). The intervention lasted for 8 weeks and various assessments were conducted including the Victorian Institute of Sport Assessment-Patella (VISA-P), Visual Analogue Scale (VAS), Y-balance Test (YBT), Modified Thomas Test (MTT), Horizontal Jumping Distance, Maximum Isometric Muscle Strength Test, musculoskeletal ultrasound for patellar tendon thickness and blood flow, and electromyography (EMG) of lower extremity muscles. Results showed significant improvement in knee joint function across all intervention methods, with the Combined group showing the most improvement. Follow-up at week 16 indicated continued improvement in VISA-P scores for the Combined and HSR groups, while a decrease was observed in the TUS group. Compared to pre-intervention, all groups showed significant differences in post-intervention VAS scores (p < 0.01), indicating a reduction in pain. While no significant differences in VAS scores were present among groups pre-intervention, post-intervention results revealed significant differences between the Combined and HSR groups (p < 0.05), as well as between the Combined and TUS groups (p < 0.01). The MTT test demonstrated notable improvements in joint mobility and quadriceps flexibility in the Combined and HSR groups after the 8-week intervention (p < 0.01), with no significant changes observed in the TUS group. Inter-group comparisons did not show significant differences both before and after the intervention. YBT test results also indicated significant differences.
Conclusion: Both exercise intervention and high-dose TUS can moderately decrease pain and improve motor capacity in patients with patellar tendinopathy. However, the therapeutic effect of high-dose TUS alone is relatively limited compared to exercise intervention. The combined application of both methods results in the most significant improvement in pain relief and motor function enhancement. The trial was registered on ISRCTN11447397 (www.ISRCTN.com) on 17/02/2024(Retrospectively registered).