Gait in patients with knee osteoarthritis : effects of preoperative physical therapy and two surgical interventions

Abstract

Introduction: Knee osteoarthritis is a common joint disease with impact on all different aspects of health. This thesis will focus on time and distance measurements of gait and clinical tests in patients with knee osteoarthritis (OA). The overall perspective of the thesis is that of a physical therapist.

Aim: The overall aim of this thesis was to evaluate gait in patients with knee osteoarthritis after a preoperative physical therapy training programme and two surgical interventions.

Methods: Study I. Thirty-four patients were randomised to a preoperative physical therapy exercise programme during 5 weeks before surgery while 34 patients received no treatment. Outcome measures were: Patient's opinion of knee functioning, pain during walking, passive range of motion (PROM), a step test, measurements of isokinetic muscle strength, time distance measurements of gait and sagittal knee flexion/extension during gait. Study II: Twenty-three patients operated with a high tibial osteotomy (HTO) and 36 patients operated with a unicompartmental knee arthroplasty (UKA) were evaluated before and one year after surgery with patients opinion of knee functioning, pain during walking, PROM, a step test, the British Orthopaedic Association (BOA) score, measurements of isokinetic muscle strength, time distance measurements of gait and sagittal knee flexion/extension during gait. Study III: A five year follow-up study including 18 patients operated with a HTO and 22 patients operated with a UKA. Outcome measures were patient's opinion of knee functioning, pain during walking, PROM, a BOA score and time distance measurements of gait. Study IV: Slow, normal and fast walking speed was evaluated in 39 patients with unilateral knee OA and 15 patients with bilateral knee OA before and one year after surgery.

Results: Study I: The patient's opinion of the functioning of the knee and the capability to descend stairs improved after the preoperative physical therapy exercise programme. The other outcome measures showed no differences after treatment. Study II: Both groups of patients improved after surgery, with no differences between the groups. Time distance measurements of gait and the sagittal knee flexion/extension during gait indicated a greater improvement in patients operated with an UKA compared to patients operated with a HTO. Study Ill: Time distance measurements of gait could detect differences in treatment outcome between groups 3 months after surgery, while the clinical measurements, as given here could not. Study IV: Patients with unilateral disease walked faster one year after surgery and the increase was similar for all walking speeds.

Conclusions: A preoperative physical therapy programme aiming at improving PROM and muscle strength can in a short perspective improve the patient's opinion of the functioning of the knee and the capability to descend steps. A step test is recommended instead of measurements of isokinetic muscle strength in this group of patients. One year after surgery, time distance measurements of gait indicated a greater improvement in patients operated with a UKA compared to patients operated with a HTO. Time distance measurements of gait could at one test occasion differentiate between the two surgical procedures while the clinical measurements could not. This data based on a 5 year follow-up conclude walking speed as a relevant outcome measure after surgery in patients with knee OA. Normal walking speed is recommended in clinical testing.