Distinct hip–knee coordination patterns in individuals with hip osteoarthritis as measured by cyclograms

Background

Hip osteoarthritis (HOA), involving cartilage degeneration and altered load distribution, disrupts gait biomechanics. While joint coordination plays a key role in efficient walking, dynamic inter-joint coordination changes across HOA progression remain underexplored.

Research question

Do inter-joint coordination patterns differ between healthy individuals and those with HOA? How does HOA severity affect inter-joint coordination, as analysed through hip-knee cyclograms and coupling angles?

Methods

Using a publicly available dataset, we analyzed 78 healthy individuals and 96 HOA participants, categorized into three subgroups based on Kellgren–Lawrence (KL) grade. The inter-joint coordination outcome measures included cyclograms perimeter, area, and coupling angle. ANCOVA (covariates: walking speed/weight/BMI) was conducted to examine differences in cyclogram area/perimeter between groups, while MANCOVA was performed to analyse differences in inter-joint coordination patterns between groups. Post-hoc comparison tests were performed where overall significance was observed using multiple t tests.

Results

Cyclogram area, perimeter, and coupling angle differed significantly between healthy and HOA groups (all p < 0.001), but not among HOA severity subgroups. Healthy individuals showed in-phase coordination pattern during mid-stance, whereas individuals with HOA displayed proximal coordination. In individuals with HOA, the coordination pattern shifted from proximal to anti-phase earlier than in healthy individuals during terminal stance and early pre-swing. No significant difference in coordination pattern during the swing phase was observed between healthy individuals and individuals with HOA.

Significance

Hip-knee coordination patterns may serve as a biomechanical marker of HOA-related gait dysfunction, offering a potential avenue for prompt intervention and management of the disease.