Front Cover: The template:functional monomer mole ratio determines the timolol binding affinity of N,N-dimethylacrylamide and tris(trimethylsiloxy)sililpropyl methacrylate imprinted hydrogels. Only with a low proportion of timolol, cavities with the maximum multiple-point binding ability are created and hydrogels able to control timolol release are obtained. Further details can be found in the Full Paper by H. Hiratani,* Y. Mizutani, and C. Alvarez-Lorenzo on page 728.

Background: Sex-based biomechanical differences during a drop vertical jump (DVJ) may explain the increased risk of anterior cruciate ligament injury in females. Video motion capture using artificial intelligence (VMocap) is a new method for accurate motion analysis. Purpose: To use VMocap to identify sex-based differences in biomechanics during a DVJ in Asian athletes. Study Design: Controlled laboratory study. Methods: A total of 63 female and 61 male Asian soccer players volunteered for this study in 2018. Participants performed a bilateral DVJ using VMocap, and the knee valgus angle (KVA), knee flexion angle (KFA), hip flexion angle (HFA), and lower leg anterior inclination angle (LAIA) were calculated from the motion capture data. These joint angles and inclination angles were evaluated at the time of highest point of the first jump (H1), initial contact (IC), maximum knee flexion (MKF), toe-off (TO), and highest point of the second jump (H2). The unpaired t test was used to compare sex-based differences. Results: At H1, the KVA in females showed more valgus (−2.9° vs −5.4°) and the LAIA in females was greater (29.1° vs 25.7°) versus males ( P < .01 for both). At IC, the KVA in females showed more valgus (−1.3° vs −3.0°) and females had a greater KFA (20.8° vs 14.3°) and LAIA (5.1° vs 0.0°) compared with males ( P < .01 for all). At MKF, female KVA showed more valgus (6.2° vs −9.5°), and females had greater LAIA (36.6° vs 34.6°), smaller KFA (77.5° vs 87.5°), and smaller HFA (55.8° vs 82.0°) compared with males ( P < .01 for all). At TO, female KVA showed more valgus (−0.7° vs −3.1°) and female KFA, HFA, and LAIA were greater (31.7° vs 19.2°; 19.9° vs 16.4°; and 18.2° vs 11.5°, respectively) than males ( P < .01 for all). At H2, females had a greater KFA (18.6° vs 14.6°) and LAIA (13.3° vs 9.9°) than males ( P < .04 for both). Conclusion: Asian female soccer players showed increased KVA and LAIA, decreased KFA and HFA at MKF, and increased KFA at IC and TO compared with their male counterparts in this analysis of the DVJ. Clinical Relevance: Elucidation of kinematic differences between the sexes can aid in predicting injuries.

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Background: Previous studies have attempted to determine whether certain risk factors can predict the occurrence of inversion ankle sprains in male collegiate soccer players. However, no consensus has been reached on the predictive risk factors of inversion ankle sprain in this population. Purpose: To identify risk factors for inversion ankle sprains among male collegiate soccer players. Study Design: Cohort study; Level of evidence, 2. Methods: Included were 145 male collegiate soccer players in Japan who were assessed during a preseason medical checkup for potential risk factors of inversion ankle sprain. The preseason assessment included anthropometric measurements, joint laxity and flexibility, muscle flexibility, muscle strength, and balance ability, with a total of 33 variables. The participants were monitored during the 2019 season for inversion ankle sprains as diagnosed by physicians. Results: A total of 31 inversion ankle sprains in 31 players (21.4%) occurred during the season. Only the measured isometric hip abductor strength was significantly lower in injured players as compared with uninjured players. Logistic regression analysis revealed measured hip abductor muscle strength deficit as a significant risk factor for inversion ankle sprain (odds ratio, 0.978 [95% CI, 0.976-0.999]; P = .05). Conclusion: Hip abductor strength deficit was a risk factor for inversion ankle sprain in the study population. This finding could be useful for the prevention of inversion ankle sprains in male collegiate soccer players.