[Evaluation of unilateral total hip arthroplasty by a quantitative analysis of gait]

The purpose of this prospective study was to assess changes in gait parameters after unilateral total hip arthroplasty and to correlate these objective changes with the results of subjective analyses.

Thirty-eight patients (21 women, 17 men; mean age 61 years) with unilateral degenerative hip disease were evaluated in order to investigate preoperative and postoperative gait characteristics with the use of a gait evaluation mat (Gait Rite, USA). Each patient underwent at least two postoperative gait evaluations in the sixth and twelfth months, respectively. Gait evaluations were also made in a control group of 50 individuals without any neuromuscular and skeletal disease. Clinical evaluations were made using the Harris hip scoring system.

All patients exhibited poor subjective evaluations preoperatively (Harris hip score <70). Compared to controls, patients had decreased step length and velocity, but increased stance, step, double support and swing times. Postoperatively, gait characteristics did not differ from those elicited prior to surgery in the first six months; however, patients attained near-normal velocity in the twelfth month. The recorded values for step length, step time, and double support time were similar to those of controls in both extremities.

This study showed that total hip arthroplasty considerably improved the gait characteristics of patients with degenerative arthritis, and that this improvement could be measured and recorded quantitatively with the use of a walking band.