Abstract
INTRODUCTION AND AIM: This study aimed to identify isokinetic strength variables of the shoulder rotator muscles that are associated with the risk of upper limb injuries in elite judokas, and to establish predictive cut-off values for injury risk using a prospective cohort design. STUDY DESIGN: Prospective cohort study. METHODS: Fifty-three male national team judokas Fifty-three male judokas of the national teams (Mean ± SD, age 18.68 ± 3.08 years, weight 75.34 ± 11.62 kg, height 175.28 ± 7.24 cm) participated in this study. We assessed concentric (CON) and eccentric (ECC) peak torque (PT) values at 60º/s and 300º/s, and the strength status of ER/IR muscles, such as the traditional ipsilateral strength deficit (ER/IR), ER/ER, IR/IR, and the non-dominant (ND) ER/IR: dominant (DOM) ER/IR (ERIR: ERIR), known as the bilateral strength asymmetry. Additionally, we recorded the ratio of Eccentric External (ECC ER) / Concentric Internal rotation (CON IR) before judo activity. The isokinetic Biodex system measured all of the variables. The injury occurrences were recorded during the 10-month follow-up period in the judo national team camps from 2020 to 2021. RESULTS: We followed fourteen upper limb sport injuries among the 53 judokas. Assessing shoulder rotator muscle strength, particularly in the eccentric mode, played a significant role in shoulder risk factor identification. Significant accuracy of ipsilateral PT deficit ECC ER/IR at (ND) 60º/s (OR 0.973, 95% CI 0.951 to 0.996, p = 0.024), as well as the bilateral PT deficit ECC ERIR: ERIR ratios 60º/s (OR 0.043, 95% CI 0.002 to 0.728, p = 0.029) discriminated between injured and uninjured judokas. The optimal cut-off point of the ND ER/IR ratio associated with the uninjured judokas group was 72.7 (sensitivity, 0.667; specificity, 0.643). DISCUSSION: The findings of the present study suggest that incorporating pre-participation testing of ipsilateral and bilateral shoulder ER/IR rotator assessment of isokinetic PT, particularly in ECC, can be valuable in an injury prevention program for judokas.