Physical exercise after knee arthroplasty: a systematic review of controlled trials

Total knee arthroplasty (TKA) is the gold standard treatment for end-stage knee osteoarthritis. Most patients report successful long-term outcomes and reduced pain after TKA, but recovery is variable and the majority of patients continue to demonstrate lower extremity muscle weakness and functional deficits compared to age-matched control subjects. Given the potential positive influence of postoperative rehabilitation and the lack of established standards for prescribing exercise paradigms after TKA, the purpose of this study was to systematically review randomized, controlled studies to determine the effectiveness of postoperative outpatient care on short- and long-term functional recovery. Nineteen studies were identified as highly relevant for the review and four categories of postoperative intervention were discussed: 1) strengthening exercises; 2) aquatic therapy; 3) balance training; and 4) clinical environment. Optimal outpatient physical therapy protocols should include: strengthening and intensive functional exercises given through land-based or aquatic programs, the intensity of which is increased based on patient progress. Due to the highly individualized characteristics of these types of exercises, outpatient physical therapy performed in a clinic under the supervision of a trained physical therapist may provide the best long-term outcomes after the surgery. Supervised or remotely supervised therapy may be effective at reducing some of the impairments following TKA, but several studies without direct oversight produced poor results. Most studies did not accurately describe the "usual care" or control groups and information about the dose, frequency, intensity and duration of the rehabilitation protocols were lacking from several studies.