Sex and Limb Differences in Lower Extremity Alignment and Kinematics during Drop Vertical Jumps

Area of Science:

• Biomechanics
• Sports Medicine
• Orthopedics

Background:

• Sex and limb dominance influence lower extremity biomechanics.
• Understanding these differences is critical for injury prevention, particularly for anterior cruciate ligament (ACL) injuries.

Purpose of the Study:

• To investigate sex and limb differences in lower extremity alignments (LEAs) and dynamic lower extremity kinematics (LEKs) during a drop vertical jump.
• To explore potential correlations between observed LEAs and LEKs and ACL injury risk.

Main Methods:

• A 2-by-2 mixed model MANOVA was used to compare LEAs and joint kinematics between sexes and limbs (dominant vs. non-dominant).
• One hundred healthy participants of Korean ethnicity performed a drop vertical jump, with LEAs and LEKs measured for both dominant and non-dominant limbs.

Main Results:

• Females exhibited greater pelvic tilt, femoral anteversion, and Q-angle, with reduced tibial torsion compared to males.
• Females demonstrated increased knee extension and ankle plantarflexion, reduced hip abduction and knee adduction, and altered peak joint movements.
• The non-dominant limb showed increased hip and knee flexion, internal rotation, and ankle inversion, alongside altered peak joint kinematics.

Conclusions:

• Observed LEAs and LEKs in females and non-dominant limbs may indicate a higher risk of anterior cruciate ligament injuries.
• These findings highlight the importance of considering sex and limb dominance in biomechanical analyses and injury prevention programs.