Lower limb biomechanics during low- and high-impact functional tasks differ between men and women with hip-related groin pain

Key points

1. 01Compared lower limb biomechanics between 65 men and 23 women with hip-related groin pain during walking (low impact) and a single-leg drop jump (high impact).
2. 02Hip and knee differences between sexes depended on the task, while ankle differences (greater dorsi-flexion moment and impulse in men) were consistent across both tasks.
3. 03Men walked with lower hip flexion, internal rotation, and adduction angles than women, partly explained by less anterior pelvic tilt.
4. 04The authors argue against pooling male-dominated cohort data without accounting for sex, since women are under-represented in this literature.
5. 05No healthy control group was included, so the cause of the differences (sex, pain, or both) could not be determined.

How it was conducted

Design

Cross-sectional study of sub-elite Australian Football and soccer players with hip-related groin pain

Participants

65 men and 23 women with hip-related groin pain (total 88)

Tasks

Walking at self-selected speed (low impact) and a single-leg drop jump (high impact)

Measurements

Hip, knee, and ankle joint kinematics and kinetics via 10-camera motion capture and two force plates

Analysis

Two-sample t-tests within statistical parametric mapping (spm1D) for continuous traces; t-tests for impulse, alpha 0.05

What they found

• Walking, hip: men had lower hip flexion angle (initial contact to toe off, P<0.001) and lower internal rotation angle (~16% to 92% of stance, P<0.001) than women.
• Walking, hip: men had a lower hip adduction angle (~13% to 35% of stance, P=0.017; ~36% to 43%, P=0.046) and lower adduction moment (~29% to 32% of stance, P=0.035).
• Walking, knee: men had a lower knee flexion angle (~70% to 86% of stance, P=0.025) and lower knee flexion moment (~85% to 91% of stance, P=0.028); knee extension moment impulse was greater in men (P=0.020).
• Walking, ankle: men had a greater dorsi-flexion angle in early stance (~0% to 20%, P=0.009), greater dorsi-flexion moment (~36% to 52%, P<0.001; ~57% to 83%, P<0.001), and greater impulse (P<0.001).
• Single-leg drop jump: men had a lower hip flexion angle in early stance (~2% to 22%, P=0.030), greater knee flexion moment (~65% to 80%, P=0.001), and greater ankle dorsi-flexion moment (~61% to 92%, P<0.001) and impulse (P=0.010).
• Demographics: men were taller (1.81 m vs 1.66 m, P<0.001), heavier (80.1 kg vs 61.7 kg, P<0.001) and had longer pain duration (36.0 vs 24.0 months, P=0.048); age, pain rating, walking speed, iHOT33 and HAGOS subscales did not differ.

Limitations

• Cross-sectional design with no healthy control group, so it cannot distinguish inherent sex differences from differing responses to pain.
• Women were under-represented (26% of the sample), limiting how confidently the female findings generalise.
• Walking speed was not controlled, so women may have walked at a faster normalised speed due to shorter stature.
• Both unilateral and bilateral cases were included, and men had longer pain duration, either of which could have influenced the biomechanics.

Why it matters

For patients

If you have hip-related groin pain, your sex may shape how you move during walking and jumping, so assessment and advice may need to be tailored rather than assumed from male-based research.

For clinicians

Avoid extrapolating biomechanical findings from male-dominated hip-related groin pain cohorts to women, and consider sex when assessing movement strategies at the hip, knee, and ankle.

For readers

This study highlights that women are under-represented in hip pain biomechanics research and that pooling sexes may obscure real differences.