Background: As more patients undergo knee arthroplasty for osteoarthritis, strategies to reduce hospital stay and the time to regain function becomes increasingly important. Physical therapy is routinely recommended after knee arthroplasty, but its benefit has not been systematically assessed. Minns Lowe and colleagues studied the effectiveness of physical therapy after hospital discharge in patients who had knee arthroplasty.

The Study: The study included a search of several electronic databases to identify randomized controlled trials of physical therapy after knee arthroplasty. Major journals and the proceedings of appropriate conferences were also searched for references to appropriate trials. Eligible trials compared physical therapy with usual care or compared different forms of physical therapy. The most common forms of physical therapy were isometric or simple strengthening exercises, stretches, or range-of-motion exercises. Out-come measures included functional activities of daily living, quality of life, walking ability, muscle strength, and range of motion of the knee joint. Outcomes were assessed three to four months and one year after surgery.

Results: Out of 27 identified studies, six were eligible for systematic review and five were eligible for meta-analysis. Five studies used standardized scoring scales to assess knee function. Three of these studies reported no significant difference between the intervention and control groups; one reported a significant benefit with physical therapy; and one reported a benefit with physical therapy at four and six months, but not at 12 months. Overall, the meta-analysis found a small to moderate benefit with physical therapy at three or four months, but no effect at 12 months.

Out of the three trials using walking as the principal outcome, two reported no significant difference between groups and no net influence on walking at three or 12 months. The three studies using quality-of-life measures as outcomes had differing results. Overall, the studies indicated a small effect in favor of physical therapy at three or four months, but the effect was not statistically significant and was no longer evident at 12 months.

Conclusion: The authors conclude that exercises based on functional activities provide short-term benefit after hospital discharge in patients who had knee arthroscopy. Small to moderate benefits in range of motion and quality of life occur at three or four months in patients receiving physical therapy, but do not persist at one year.