Unaffected Side Hip-Knee Cyclogram for Assessing Gait and Balance in Ambulatory Hemiplegic Stroke Patients

Abstract

Purpose: Gait disturbances affect mobility and quality of life in patients with post-stroke hemiplegia. While the affected side is traditionally assessed, the evaluation of the unaffected side has remained relatively underexplored. We investigated the potential of the unaffected side's hip-knee cyclogram parameters for assessing gait and balance function in post-stroke patients. Materials and Methods: This study included 152 ambulatory patients with post-stroke hemiplegia. Participants underwent instrumented gait analysis and Berg Balance Scale (BBS) assessment. Hip-knee cyclogram parameters were derived from sagittal plane joint angles during gait. Correlations with BBS and leg length-normalized gait speed were analyzed. Subgroup analyses focused on stiff-knee gait and severity of spasticity. Results: Swing phase area of the unaffected side showed moderately strong correlations with clinical parameters (BBS: rho=0.66, leg length-normalized gait speed: rho=0.81) and also correlated with the single-limb support-phase ratio (rho=0.69) and normalized maximal vertical ground reaction force (rho=0.60) on the affected side. The unaffected hip-knee cyclogram demonstrated greater consistency across multiple gait cycles, as indicated by a smaller standard deviation and lower variability in joint coordination. In subgroups with stiff-knee gait and severe spasticity, the unaffected side's swing phase area and perimeter demonstrated stronger correlations than those of the affected side. Conclusion: The hip-knee cyclogram parameters reflected gait function in patients with post-stroke hemiplegia, with the swing phase area of the unaffected side showing stronger correlations with clinical measures and more consistent results.