Are Postoperative Hip Precautions Necessary After Primary Total Hip Arthroplasty Using a Posterior Approach? Preliminary Results of a Prospective Randomized Trial

J Arthroplasty. 2020 Jun;35(6S):S246-S251. doi: 10.1016/j.arth.2020.02.019. Epub 2020 Feb 15.


Background: It is unclear whether posterior hip precautions after primary total hip arthroplasty (THA) reduce the incidence of early postoperative dislocation.

Methods: We performed a prospective randomized study to evaluate the effect of hip precautions on incidence of early dislocation after primary THA using a posterior approach. Between January 2016 and April 2019, 587 patients (594 hips) were consented and randomized into restricted or unrestricted groups. No significant demographic or surgical differences existed between groups. The restricted group was instructed to refrain from hip flexion >90°, adduction across midline, and internal rotation for 6 weeks. 98.5% (585 of 594) of hips were available for minimum 6-week follow-up (291 restricted and 294 unrestricted). Power analysis showed that 579 hips per group are needed to demonstrate an increase in dislocation rate from 0.5% to 2.5% with 80% power.

Results: At average follow-up of 15 weeks (range, 6-88), there were 5 dislocations (incidence, 0.85%). Three posterior dislocations occurred in the restricted group at a mean of 32 days (range, 17-47), and 2 posterior dislocations occurred in the unrestricted group at a mean of 112 days (range, 21-203), with no difference in dislocation rate between groups (1.03% vs 0.68%; odds ratio, 0.658; 95% confidence interval, 0.11-3.96; P = .647). At 6 weeks, unrestricted patients endorsed less difficulty with activities of daily living, earlier return to driving, and more time spent side sleeping (P < .05).

Conclusion: Preliminary analysis suggests that removal of hip precautions after primary THA using a posterior approach was not associated with early dislocation and facilitated return to daily functions. Investigation to appropriate power is warranted.

Keywords: dislocation; hip precautions; posterior approach; postoperative restrictions; prospective randomized trial; total hip arthroplasty.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Activities of Daily Living
  • Arthroplasty, Replacement, Hip* / adverse effects
  • Hip Dislocation* / epidemiology
  • Hip Dislocation* / etiology
  • Hip Dislocation* / prevention & control
  • Humans
  • Postoperative Period
  • Prospective Studies
  • Retrospective Studies