A pilot, feasibility randomised, controlled trial comparing walking exercise against pendulum leg swinging exercise in adults with osteoarthritis of the knee. (Preprint)
Authors: Xia Zhidao , Huang Lixia , Esser Patrick , Dawes Helen , Wade Derick , Song Jiuhong 
Published: November 2023

BACKGROUND

In China, swinging the leg backwards and forwards is a commonly used therapy for people with osteoarthritis of the knee. One rationale is that movement without weightbearing may reduce pain of the knee by strengthening the muscles and changing the dynamic pressure of at the at the knee. There have been no studies evaluating its effectiveness.

OBJECTIVE

Before undertaking a large trial, a pilot study is needed to establish feasibility and an estimate of the sample size needed.

METHODS

This will be a parallel-group, assessor-masked, randomised, controlled study comparing the effect of pendulum leg swinging against an equivalent time of walking exercise. Patients will be recruited from the outpatient and inpatient orthopaedic surgery services in a large, class III general hospital in Wuhan, China. To be selected they must have clinically diagnosed osteoarthritis of the knee. Patients will be excluded if they have additional knee disease, have had hip or knee arthroplasty or a tibial osteotomy, are taking steroids or have done so in the preceding three months, have another illness affecting mobility or participation in the study, are pregnant, or have a body mass index (BMI) over 35. They will be allocated randomly using sealed, prefilled envelopes on a 1:1 basis. Data will be collected by masked observers at baseline and 12 weeks with additional 12 weeks follow-up. Measures include the Oxford Knee Score, the six-minute walking distance, pain measured on a numerical rating scale, the 30 second sit-to-stand test, quadriceps muscle strength, and accelerometer data. Feasibility data will record data-completion rates, recruitment and retention rates, adherence with treatment, and patient experience including adverse events. The two interventions will involve a gradual increase of exercise between baseline and 6 weeks with a further six weeks at the level set for each patient. Data analysis will be descriptive, with comparative analysis on outcome measures to give an estimate of sample size needed in a full trial.

RESULTS

This feasibility trial started in October 2021 and completed in October 2022. A total of 174 participants were recruited and 50 patients were accepted for this trial. There were 24 cases in control (walking) group and 26 in KOAPT group. All patients completed 12 weeks intervention and 12 weeks follow-up.

CONCLUSIONS

Swinging the leg like a pendulum combines exercise and movement of the knee without bearing weight. Exercise is known to give some benefit but it is not known whether joint movement without weight-baring has any beneficial effect. A large trial would be needed. This trial will establish how feasible it might be to undertake a large trial.

CLINICALTRIAL

Registry: Chinese Clinical Trial Registry
Number: ChiCTR2100051275
Date: 17th September 2021
URL: https://www.chictr.org.cn/historyversionpuben.aspx?regno=ChiCTR2100051275