838 MEP034 – Biomechanical response to soccer cleat stud shape and fatigue state: implications for injury risk reduction in female athletes

AbstractBackground Soccer footwear is predominantly designed according to male mechanics, despite known sex differences in movement patterns and joint loading. Traction and fatigue may affect female exposure to torsional injury mechanisms related to ACL injury. Objective This study investigates the influence of soccer cleat stud shape, elliptical and bladed, on the knee mechanics of athletes pre- and post-fatigue. We hypothesized that bladed cleats, with higher rotational resistance, will increase knee loading in females, which will worsen with fatigue. Design A randomized cross-over design assigned participants a different cleat condition per visit. Setting Data were collected over two sessions in a turfed biomechanics facility equipped with force plates and motion capture. Participants Ten competitive college-aged soccer athletes (5 male, 5 female) participated in this study (20 participants in progress), ranging from NCAA Division III to local league members. Athletes had no recent lower extremity injury nor history of ACL injury. Assessment of Risk Factors Independent variables included cleat stud shape (elliptical, bladed), and fatigue state (pre, post). Knee joint mechanics were assessed using inverse dynamics during unanticipated cutting maneuvers before and after a sport-specific fatiguing protocol. Outcome Measurements Dependent variables included peak knee flexion, peak knee valgus, knee extensor moment and anterior tibiofemoral shear force. Mixed effects ANOVA examined main and interaction effects of sex, cleat condition, and fatigue state.Results Preliminary analyses (table 1) found a significant main effect of fatigue state on knee extensor moment (p = 0.018). No other main or interaction effects were observed. Trends in descriptive statistics suggest the presence of sex differences in mechanical landing strategy. Conclusions Initial findings show a protective effect of fatigue on knee extensor moment. Interesting trends suggest cleat and sex interactions, however current sample size is insufficient to confirm those observations. Increased sample size should help substantiate these interim findings.View this table:View inline View popup Download powerpoint Abstract 838 Table 1 Female and male knee mechanics during cutting task