Gait adaptations in patients with longstanding hip fusion.

PURPOSE To examine the long-term effects of hip arthrodesis in terms of gait adaptations. METHODS Motion analysis was performed on 9 patients who underwent unilateral hip arthrodesis between 1979 and 1991. A standard clinical gait analysis 3-dimensional model for the lower limb was used to calculate the effect of the fused hip on walking, compared with the contralateral normal hip. RESULTS Significant (p<0.05) gait adaptations noted in the fused side were, compensatory hip hiking during the swing-phase, a 24% reduction in hip adduction moment, a 37% decrease in genu-varus moment, 80% reduced hip power, and excessive pelvic tilt. CONCLUSION It appears that the excess pelvic tilt observed was to achieve relative hip extension via increased relative lumbar lordosis, while the decreased coronal plane moments of the hip and knee observed were to reduce joint loading on the affected side.