Short-term recovery of balance control after total hip arthroplasty

Hip osteoarthritis leads to chronic pain and deteriorated joint function, which affect weightbearing and balance during gait. THA effectively restores hip function but it is not known whether THA restores balance during gait. We hypothesized patients would have greater frontal plane and smaller sagittal plane center of mass-center of pressure inclination angles preoperatively compared with control subjects, and THA would improve these inclination angles by 16 weeks postsurgery. Compared with control subjects, we observed greater frontal plane inclination angles and smaller sagittal plane angles preoperatively, indicating gait imbalance. These inclination angles were improved postoperatively, providing better balance control. Despite improvement, patients differed in frontal and sagittal plane inclination angles compared with control subjects. This suggests residual deficits in dynamic balance control in patients undergoing THA before and up to 4 months after surgery.