Three-dimensional gait analysis in women with a total hip arthroplasty

Objectives. The purposes of this study were: (1) to identify the primary (h ip) and secondary (neighboring joints) impairments during gait in subjects with a total hip arthroplasty total hip arthroplasty, (2) to determine whic h impairments persist when controlling for gait speed and (3) to study the relationships between primary and secondary impairments in order to describ e the locomotor strategies used by these patients. Design. This cross-sectional study compared the gait patterns of women with a total hip arthroplasty to those of healthy women. Background. Several studies have reported residual hip impairments in the s agittal plane during gait after a total hip arthroplasty. There is, however , a substantial lack of knowledge in regard to the changes at the neighbori ng joints and in the other planes of movement. Methods. Subjects have been examined during a gait laboratory testing sessi on including the simultaneous recording of three-dimensional kinematics and ground reaction forces on one side, and bilateral activation of six lower limb muscles. Results. A significant decrease of 20% in the hip extensor moment of force during the early stance phase was correlated (R-2 = 43%) with a significant decrease of 14% in gait speed. Moreover, a significant decrease of 59% in the range of hip extension at the end of the stance phase was observed toge ther with secondary impairments such as a significant increase in the anter ior pelvic rotation, in knee flexion and in ankle dorsiflexion. Lastly, a s ignificant increase in ipsilateral bending of the trunk during the single l imb support on the operated limb was concomitant with a significant decreas e in the hip abductor moment of force. Conclusions. The decrease in gait speed and the persistence of abnormal gai t patterns one year after the total hip arthroplasty were associated respec tively with a decrease in the hip extensor moment of force and with a decre ase in the range of hip extension (sagittal plane) or in the hip abductor m oment of force (frontal plane). (C) 2000 Elsevier Science Ltd. All rights r eserved.