There is a Lack of Clinical Homogeneity in Lower-Limb Tendinopathy Trials: A Scoping Review.

OBJECTIVE: It is unclear if clinical trials of treatments for lower-limb tendinopathies include clinically homogeneous participant populations (an assumption for pooling in meta-analyses). We assessed the recruitment setting and participant characteristics used in randomized controlled trials (RCTs) that were investigating any treatment for lower-limb tendinopathies. DESIGN: Scoping review. METHODS: We conducted a systematic literature search in the PubMed, Embase, Cochrane CENTRAL, and Web of Science databases. All RCTs that were investigating treatments for lower-limb tendinopathies in an adult population (≥18 years) were eligible for inclusion. At least 2 authors conducted independent screening and selection of full-text papers, and extracted data from included studies. RESULTS: Of 18 341 records, 342 RCTs (21 897 participants) were eligible for inclusion and data extraction. The most common diagnoses were plantar fasciopathy (n = 195, 57%), Achilles tendinopathy (n = 82, 24%), and patellar tendinopathy (n = 41, 12%). Secondary care (n = 144, 42%) was the most reported recruitment setting, followed by an open setting (n = 44, 13%). In 93 (27%) RCTs, the recruitment setting was not described. We found high heterogeneity in participant characteristics (eg, symptom duration, age, body mass index, and the Victorian Institute of Sport Assessment [VISA] questionnaire score) within and between recruitment settings. CONCLUSION: Our results question whether clinical homogeneity can be adequately assumed in clinical trials of lower-limb tendinopathies due to the lack of clear reporting of the recruitment setting and the variability within and between recruitment settings of key participant characteristics. These findings threaten assumptions for meta-analyses in lower-limb tendinopathies. J Orthop Sports Phys Ther 2024;54(1):1-10. Epub 5 December 2023. doi:10.2519/jospt.2023.11722.

Muscle Activation Differences During Eccentric Hamstring Exercises.

BACKGROUND: The hamstring muscles play a critical role in the prevention of lower limb injuries. However, it is still unclear which exercises are more effective in terms of muscle activation. HYPOTHESIS: In healthy individuals, there are differences between muscular activations of the biceps femoris (BF), semitendinosus (ST), and semimembranosus (SM) muscles during eccentric hamstring exercises. STUDY DESIGN: Cross-sectional. LEVEL OF EVIDENCE: Level 2. METHODS: A total of 31 healthy participants (18 male; mean age, 22.5 years; SD, 3.1) were included in this study. The maximum voluntary isometric contraction of the hamstring muscles was measured using an isokinetic dynamometer. The participants were asked to perform one of the following exercises randomly (3 repetitions each): stiff-leg deadlift (SLDL), unilateral stiff-leg deadlift (USLDL), Nordic hamstring exercise (NHE), and ball leg curl (BLC). Activation of the BF, ST, and SM muscles was measured using surface electromyography during the exercises. In the statistical analysis of this study, factorial analysis of variance was used to compare the effects of each exercise on the muscle groups and to analyze which exercise type was more effective for each muscle group. RESULTS: The NHE led to higher muscle activation than the other exercises (P < 0.001). When exercise type and muscle interaction were examined, SM activation was lower than BF (P = 0.04) and ST (P = 0.001) during NHE (P < 0.05). The highest level of muscular activation was recorded during the NHE in both male and female participants. CONCLUSION: The NHE may be the most effective exercise for the hamstring muscles as it leads to greater muscle activation. SLDL, USLDL, and BLC exercises may be preferred at the beginning of strength training programs since they lead to lower muscular activation compared with the NHE. CLINICAL RELEVANCE: To select the optimum hamstring exercise, it is important to know the activation levels of the hamstring muscles during different eccentric exercises.