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Published on: September 13, 2015
Association between preparatory muscle activation and peak valgus knee angle
Riann M Palmieri-Smith1, Edward M Wojtys, James A Ashton-Miller
1Division of Kinesiology, University of Michigan, 401 Washtenaw Avenue, Ann Arbor, MI 48109-2214, United States. riannp@umich.edu
Summary
Women exhibiting higher valgus knee angles (VKA) may have increased risk for anterior cruciate ligament (ACL) injuries. Specific preparatory muscle activation patterns in females, unlike males, correlate with VKA during hopping.
Area of Science:
- Biomechanics
- Sports Medicine
- Neuromuscular Physiology
Background:
- Valgus knee angle (VKA) is a potential indicator for non-contact anterior cruciate ligament (ACL) injuries.
- Differences in VKA between sexes may stem from pre-programmed muscle activation strategies.
- Understanding the relationship between VKA and preparatory muscle activity is crucial for injury prevention.
Purpose of the Study:
- To investigate the association between peak VKA and preparatory muscle activity during a forward hop.
- To determine if sex-specific differences exist in this relationship.
- To identify potential neuromuscular strategies for reducing ACL injury risk in females.
Main Methods:
- Twenty-one adults performed five forward hop trials.
- Lower extremity kinematics and surface electromyography (EMG) were recorded.
- Multiple linear regressions analyzed the relationship between peak VKA and preparatory muscle activity (100ms pre-contact) in female, male, and combined groups.
Main Results:
- In females, higher peak VKA correlated with increased vastus lateralis and lateral hamstring activity, while lower VKA correlated with increased vastus medialis activity (P<0.05).
- No significant association between preparatory muscle activity and peak VKA was found in males or the combined group (P>0.05).
Conclusions:
- Sex-specific preparatory muscle activation patterns influence VKA in females.
- Neuromuscular training focusing on balanced medial-to-lateral quadriceps and hamstring activation may mitigate ACL injury risk in females.
- Targeted interventions could help reduce ACL injury incidence.
