A comparison of a less invasive piriformis-sparing approach versus the standard posterior approach to the hip: A randomised controlled trial.
We undertook a randomised controlled trial to compare the piriformis-sparing approach with the standard posterior approach used for total hip replacement (THR). We recruited 100 patients awaiting THR and randomly allocated them to either the piriformis-sparing approach or the standard posterior approach. Pre- and post-operative care programmes and rehabilitation regimes were identical for both groups. Observers were blinded to the allocation throughout; patients were blinded until the two-week assessment. Follow-up was at six weeks, three months, one year and two years. In all 11 patients died or were lost to follow-up. There was no significant difference between groups for any of the functional outcomes. However, for patients in the piriformis-sparing group there was a trend towards a better six-minute walk test at two weeks and greater patient satisfaction at six weeks. The acetabular components were less anteverted (p = 0.005) and had a lower mean inclination angle (p = 0.02) in the piriformis-sparing group. However, in both groups the mean component positions were within Lewinnek's safe zone. Surgeons perceived the piriformis-sparing approach to be significantly more difficult than the standard approach (p = 0.03), particularly in obese patients.  In conclusion, performing THR through a shorter incision involving sparing piriformis is more difficult and only provides short-term benefits compared with the standard posterior approach.
University of Western Australia, Department of Surgery, Nedlands, Western Australia 6009, Australia. rjkkhan@gmail.com
R J K
RJ
Khan
D
D
Maor
M
M
Hofmann
S
S
Haebich
D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000379:methods* / Q000534:rehabilitation; D004812:Epidemiologic Methods; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000009:adverse effects / Q000379:methods / Q000534:rehabilitation; D015207:Osteoarthritis, Hip / Q000601:surgery*; D010149:Postoperative Pain / Q000209:etiology; D017060:Patient Satisfaction; D016896:Treatment Outcome; D016138:Walking