Introduction The piriformis-sparing approach is the new reform of the posterior approach. In this updated approach, stability is supposed to be better. Aim The current study aims to compare the clinical and radiological outcomes for both piriformis-sparing and piriformis sacrificing posterior approaches for THA. Patients and methods A prospective comparative experimental study was performed to compare the outcomes of piriformis-sparing versus piriformis sacrificing posterior approach total hip replacement. Thirty-five hips treated by the piriformis-sparing approach were compared with 37 treated by the standard approach. They were followed-up for 12 months. Oxford hip score (OHS) questionnaire was used to assess the clinical outcome, and plain radiography was used to assess the radiological outcome. Results There was a statistically significant difference between both groups in the OHS 1-month postoperatively with better mean score in the piriformis-sparing group (P < 0.001). Regarding the 3-month OHS, there was a statistically significant difference between both groups (P = 0.04). As regards the 12-month postoperative OHS, there was no statistically significant difference between both groups (P = 0.1). There was no significant difference in the radiological assessment of both groups. However, there was significant difference in the limb length discrepancy between both groups (P = 0.05). There was a significant difference in the dislocation rate among both groups, with less dislocation in the piriformis-sparing group. Conclusion The piriformis-sparing approach achieved the same long-term functional benefits as the standard posterior approach. Sparing the Piriformis muscle evades wasting due to tendon division and repair. Though OHS in the long run showed no difference between both groups.
Eldaly et al. (Sat,) studied this question.