A Randomized Controlled Trial: The Effectiveness of 8-weeks Progressive Strength Training to Patients With Unicompartmental Knee Replacement, Initiated Within the First Postoperative Week

The purpose and Study hypotheses:

The purpose of the study is to investigate the effect of progressive resistance training in the early postoperative phase on patients who has had unicompartmental knee replacement. The hypotheses are that this group compared to a control group will achieve greater muscle strength and functional ability in terms of gait and working capacity.

Study design:

The subjects will be randomized into two groups; intervention and control. Intervention group: strength training two times a week supervised by a physiotherapist.

Control group: Training at home, following extradited guidelines.

Endpoint:

Primary endpoint is two months postoperative. The following test will be used: muscle power test (by a Power Rig), instrumented gait analysis using a combined accelerometer and gyro-sensor in; 6 min. walk test, stair climbing test, 20 meter walking test and block step test.

Furthermore, the questionnaire KOOS will be used for monitoring every 2 weeks.

Sample size:

The power calculation is based on an expected improvement in muscle power by 25%. The risk of a type 1 error is set to 5 %, and the power is set to 80%. The calculations showed that 24 patients are needed in both groups, but 30 patient will be included in both groups to account for dropouts.

Perspectives:

This study is, to our knowledge, the first study to investigate the effect of strength training after unicompartmental knee replacement. Moreover it has , to our knowledge not been. At the moment no guidelines for rehabilitation exist, and research showed that this group of patients has a decreased function in their daily living compared with the background population. If, as expected, cases have an overall increased function compared to controls, this study can provide a basis for future rehabilitation.