Which type of exercise therapy is effective after hip arthroplasty? A systematic review of randomized controlled trials.

BACKGROUND Early multidisciplinary rehabilitation can improve the recovery after total hip arthroplasty (THA). However, optimal exercise therapy has not been defined. We aimed to answer the question: "Which type and/or timing of exercise therapy is effective following THA?" DESIGN Systematic review. METHODS We searched four databases: MEDLINE, PEDro, Cochrane Library, and Cinahl since January 2008 till December 2012. Literature before 2008 was not searched for, because it was previously analyzed by two systematic reviews. Eligible criteria for studies were: Randomized Controlled Trials (RCTs); English language; interventions on type and/or timing of physical exercise initiating after THA; outcome measures including at least one among impairment, activity, participation, quality of life, or length of stay in hospital. RESULTS Eleven papers on nine RCTs were identified. Trial quality was mixed. PEDro scores ranged from four to eight. Exercise therapy varied greatly in type and timing. Each of the nine RCTs addressed a specific issue and overall the results were sparse. In the early postoperative phase favorable outcomes were due to ergometer cycling and maximal strength training. Inconclusive results were reported for aquatic exercises, bed exercises without external resistance or without its progressive increase according to the overload principle, and timing. In the late postoperative phase (> 8 weeks postoperatively) advantages were due to weight-bearing exercises. CONCLUSION Insufficient evidence exists to build up a detailed evidence-based exercise protocol after THA. Sparse results from few RCTs support specific exercise types which should be added to the usual mobility training in THA patients.