Commentary

The study by Peak et al is an important example of how meaningful outcomes such as cost, postoperative recovery, and patient satisfaction need to be examined when accepted practices are questioned. Peak et al looked at the incidence of dislocation when currently accepted postoperative hip precautions were relaxed for a 6 week period in patients scheduled for uncemented hip arthroplasty. Among the PFR and no PFR groups, there was a single dislocation, representing a dislocation rate of 0.33%. These results compare with those of a similar study by Talbot et al, which found a 0.6% dislocation rate when no postoperative hip precautions were imposed.¹

The risk of type II error (to say there is no difference when, in fact, a difference exists) is too great to suggest otherwise. Because the dislocation rate was so low, the study had insufficient power (ie, not a large enough sample) to detect a significant difference between groups. As well, the trial was not blinded, and so the low dislocation rate could be the result of increased staff vigilance. Consequently the effect of relaxed restrictions on THA dislocations has yet to be discerned.

Fortunately, dislocation in people with uncemented THAs is clearly a rare event, and relaxation of restrictions seems unlikely to greatly increase dislocation rates. Relaxation of restrictions would increase satisfaction, promote earlier return to normal activities of daily living, and decrease direct and indirect costs. From a nursing perspective, the study by Peak et al substantiates that a specific group of patients are at low risk of dislocation and actually benefit when hip precautions are not implemented. However, the findings are only directly applicable to patients where an anterolateral approach has been used and who are similar to those recruited by Peak et al (eg, no neuromuscular compromise or hyperflexibility syndrome). For patients not meeting these criteria, hip precautions should still be used until research has determined whether relaxed restrictions are appropriate in other groups and nurses have evidenced based criteria to appropriately implement hip precautions. Cost effectiveness lies in the discriminant use of precautions. Peak et al have shown that questioning traditional practices can have substantial benefits for both institutions and individual patients. Further investigation into relaxation of restrictions in patients thought to be at higher risk of dislocation is warranted.