The association between lower extremity strength ratios and the history of injury in collegiate athletes.

CONTEXT: Strength ratios are important because imbalances in opposing muscle groups can cause articular instability and subsequently increase the risk of musculoskeletal injury (MSKI). Therefore, the purpose of this study was to evaluate the association between lower extremity (LE) musculoskeletal isometric strength ratios and the history of LE MSKI. PARTICIPANTS: One hundred eighty-two NCAA Division 1 soccer, football, volleyball, and basketball athletes. INTERVENTIONS: All isometric strength assessments were measured bilaterally using a handheld dynamometer. Strength assessments included: ankle inversion/eversion, ankle dorsiflexion/plantarflexion, knee flexion/extension, hip abduction/adduction, and hip external/internal rotation. LE MSKI history was collected through self-report; a report of the LE MSKI sustained in the one year prior to testing were collected. RESULTS: The hip external/internal rotation ratio was statistically significant for side to side differences in the non-injured (NINJ) group (p = 0.001). The dominant leg of the NINJ group had a mean external/internal rotation ratio of 1.109 ± 0.221, and the non-dominant leg had a mean ratio of 1.177 ± 0.208. CONCLUSIONS: There were no statistically significant differences between the injured (INJ) and NINJ groups. This could indicate that injury history does not play a role in current strength ratios and could suggest that the athletes in the INJ group are performing successful rehabilitation for their injuries.

Youth Distance Running and Lower Extremity Injury: A Systematic Review.

Distance running is a popular youth sport. This systematic review identified and examined the effects of youth distance running and lower extremity musculoskeletal injury. Scientific databases were searched from database inception to May 2020. Two hundred and fifty-eight full texts were screened, with nine articles retained for data extraction. Seven of the studies were case reports or case series. Two case reports involved an apophyseal hip fracture. No correlation was found between running mileage or gender and sustaining an injury. Middle school runners reported fewer injuries than high school runners. Cross country accounted for less than 10% of injuries in youth under 15 compared to other track activities. The main finding was a paucity of research. Available literature suggests youth can participate in distance running with minimal adverse effects. One exception may be increased vulnerability to growth plate injury. Additional research is needed, especially in those under 10, as literature in this population is nonexistent.