Using instrumented shoes in THA patients.

Total hip arthroplasty (THA) is a successful surgical procedure to treat orthopedic osteoarthritis. Studying the differences in movement during various activities of daily living before and after total hip replacement is important for the follow up of the patients. Instrumented force shoes (IFS) can be used to quantify the movement patterns in an outpatient setting. The first aim of this study is to investigate whether the IFS is a sufficiently sensitive instrument to show differences in mobility performance between before and after THA. Prospective cohort study with two measurement sessions: pre-operative and 6-8 months post-operative. In total 25 patients with primary osteoarthritis of the hip selected for a primary THA will perform 3 functional mobility tasks, walking, sit-to-stand, stad-to-sit, stairs ascend and stairs descend in both measurements.

The aim of this first study is to evaluate the use of the IFS for quantitative assessment of mobility performance in comparison with gait velocity and questionnaires already validated and studied in patients before and after THA in an outpatient clinical setting. If the IFS parameters appear to be sensitive, future patients shall benefit from the results because functional mobility performance before/after THA can be assessed quantitatively in a clinical setting, which can help the orthopedic surgeon in the future to evaluate the effect of THA.

Patients undergoing THA will be measured before and 6-8 months after the operation.

Patients undergoing THA will be measured before and 6-8 months after the operation. Both measurements include 3 functional mobility tasks while the subject is wearing instrumented force shoes (IFS). In the first task, the subject is instructed to walk several times through the corridor from the beginning to the predefined endpoint. Subsequently, the subject is asked to stand and sit in a chair with arms folded across the chest 5 consecutive times. The third task is to ascend and descend a total of 5 steps of a stair. Before and after each measurement a Visual Analogue Scale (VAS) will be used to score pain in the hip. Besides the VAS, after each measurement the Harris Hip Score (HHS) and the Functional capacity part of the Traditional Western Ontario and McMaster Universities osteoarthritis index (WOMAC-FC) will be administered.