Single mini-incision total hip replacement for the management of arthritic disease of the hip: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND Mini-incision total hip replacement continues the current trend in orthopaedics and other specialties toward smaller-incision surgery. The purpose of this systematic review was to assess the effectiveness and safety of single mini-incision compared with standard-incision total hip replacement for treatment of arthritis of the hip. METHODS We conducted an electronic literature search for relevant studies published in any language up to March 2010. Key conference proceedings and national orthopaedic registries were searched, professional organizations and implant manufacturers were approached, and reference lists from included studies were screened. We included randomized and quasi-randomized controlled trials assessing single mini-incision surgery, defined as an incision of ≤ 10 cm, compared with standard primary total hip replacement. Two reviewers independently assessed studies for inclusion and extracted data. RESULTS Fifteen randomized and five quasi-randomized controlled trials, involving 1857 participants, were eligible. Included trials were of mixed methodological quality, with the sample size ranging from twenty to 219. Mean follow-up periods were short, ranging from six weeks to three years. Compared with standard total hip replacement, mini-incision procedures may have small perioperative advantages in terms of less blood loss, shorter operative time, and shorter inpatient stay, but the differences were not clinically important. Few complications were reported, and the complication rate did not differ significantly between groups. There was insufficient evidence to suggest any major difference in the short-term revision rate, and confidence intervals for surrogate measures for long-term outcome were broad enough to include clinically important differences in favor of either approach. CONCLUSIONS Although there were marginal short-term advantages and disadvantages for each of the surgical techniques, there was no strong evidence either for or against mini-incision compared with standard-incision total hip replacement. Importantly, evidence on longer-term performance, especially the risk of revision arthroplasty, for mini-incision hip arthroplasty is very limited.