Background and purpose:

In the early phase after a total knee replacement (TKA), patients experience a decrease in leg muscle strength with up to about 80%. This considerable loss of muscle strength is related to reduced functional performance at this point in time. As the loss of muscle strength and functional performance is most pronounced early after TKA, rehabilitation including strength training initiated early after TKA seems a logical choice. However, tradition and fear of symptom exacerbation, such as increased knee joint swelling, knee pain and slow recovery of knee joint range of motion, have typically precluded strength training early after TKA.

Hypothesis:

Our hypothesis is that the effect of early rehabilitation including strength training will be greater than rehabilitation without strength training. If the hypothesis is confirmed, strength training early after TKA could be implemented directly into clinical rehabilitation practice.

Participants and methods:

Seventy participants with a unilateral TKA, between the age of 18 to 80 years, who understand and speak Danish, have given informed consent, will be included in this study.The study is a single-blinded randomized controlled study, where the participants receive supervised 1) rehabilitation with or 2) rehabilitation without strength training in 7 weeks. All components of the rehabilitation program (balance-, and mobility training etc.) are the same in both groups except the strength training exercises. Instead of the strength training exercises, the group without strength training spend more time on warm-up exercises, mobility- and balance exercises. The rehabilitation program lasts 1 hour per session, and will be performed twice per week. The participants perform a test battery 4 times from before to 6 months after the TKA. The test battery assesses the participants' walking ability, leg strength, knee pain, knee joint swelling- and range of motion, and self-reported function and quality of life.

Ethical issues:

From a pilot study conducted in the beginning of 2010, the investigators found, that strength training initiated early after TKA seems feasible, and does not increase knee joint swelling and knee pain. None of the financial supporters, or any of the authors, have any potential conflicts of interest with regard to the study.

Inclusion Criteria:

• Participants with a primary unilateral total knee arthroplasty.
• Age between 18 and 80 years.
• Participants must understand and speak Danish.
• Participants undergo surgery at Copenhagen University Hospital, Hvidovre, and live in the counties of Copenhagen, Brøndby or Hvidovre.

Exclusion Criteria:

• Disease/Musculoskeletal disorder, which requires special rehabilitation modality.
• Alcohol and drug abuse.
• Lack of wish to participate or unwillingness to sign an informed consent.