Most THA Patients Can Skip Hip Precautions, Study Suggests
One of the benefits of the direct anterior approach over the traditional posterior approach to total hip arthroplasty (THA) is the lower risk of early dislocation, making standard hip precautions in the weeks after surgery unnecessary.
And those precautions – not flexing the hip past 90°, not internally rotating the hip more than 10°, using an elevated seat cushion and a grabber for anything on the ground, and sleeping supine for 6 weeks – can be daunting for THA patients whose surgeons favor the posterior approach.
“The precautions can be limiting and cause fear in patients,” said Peter Sculco, MD, from Hospital for Special Surgery in New York. “Sleeping on your back is very uncomfortable for many people. You often hear from physical therapists that patients are relieved when they can finally cross their legs and sleep on their side.”
A study from Dr. Sculco and his colleagues – presented at the 2019 Annual Meeting of the American Academy of Orthopaedic Surgeons – suggests that these stringent precautions may not always be necessary. They found that low-risk patients undergoing THA with a posterior approach can skip the standard postoperative hip precautions without an increased risk of hip dislocation.
“The majority of patients we see are low risk; 90% of patients probably qualify for minimized precautions,” Dr. Sculco said.
Interestingly, there’s little data to support the standard hip precautions recommended for the posterior approach. “The current precautions are based on hip replacements done 25 years ago, and we have changed a lot in terms of improving how we do hip replacements that has given us more confidence in the stability of our hips,” Dr. Sculco said. “Our understanding of the dynamic movement of the pelvis and how we put the parts in is much different. The quality of our soft tissue repair and closure at the end of surgery is much more robust.”
When patients are on stringent precautions, they are not as active, which can hamper recovery. “If you minimize the hip precautions in an appropriate way, patients focus more on their mobility and recovery and less on the fear of how they turn their leg 10°,” Dr. Sculco said.
In the new study, the researchers retrospectively reviewed data all patients who underwent primary uncemented THA by the posterior approach between January 2014 and June 2016 at Hospital for Special Surgery. Surgeons had the choice to put patients on standard precautions or the pose-avoidance study protocol. In the study protocol, patients had to avoid only the shaving position, which combines flexion and internal rotation of the hip.
A total of 1311 patients met the inclusion criteria for the pose avoidance cohort and had a minimum follow-up of 6 weeks. The researchers then matched patients 1:1 with an historical cohort of patients treated with standard posterior hip precautions based on age, gender, and body mass index that were.
Within the first 6 postoperative weeks, 6 dislocations occurred in the pose-avoidance group (0.46%) compared with 7 in the matched group (0.53%), a difference that was not statistically or clinically significant.
“Our results suggest that the standard postoperative precautions in patients undergoing total hip arthroplasty through the posterior approach without known risk factors for instability are unnecessary,” Dr. Sculco said. “We may find that precautions don’t make sense for any of our patients, but we need to look at in a stepwise fashion.”
The study was limited in that it is not a randomized controlled trial, usually the gold standard for dictating a change in practice.
“The bottom line of the study is in recent years, we have learned more about interventions that matter after joint replacement and those that don’t really have efficacy,” Dr. Sculco said. “In most patients, we got rid of powerful anticoagulants, for example, and we are moving toward a shorter stay and even outpatient arthroplasty for total hip replacement.
“Minimizing precautions and simplifying the postoperative recovery is part of the larger simplification of surgery where we are using more selected resources and interventions for people, instead of blanketing everyone with the same kind of protocols.”
Dr. Sculco noted that there is an increasing demand for hip replacement in the US. “In 2010, there were 310,000 hip replacements in the United States and that number is increasing. It’s probably 350,000, if not more, now,” he said.
Sculco PK, Ihekweazu UN, Carroll KM, Jerabek SA, Su EP, Figgie MP, Boettner F, Sculco TP, Mayman DJ. Eliminating Standard Hip Precautions Does Not Increase the Risk of Dislocation after Contemporary Posterior Approach Total Hip Arthroplasty (Paper 140). Presented at the 2019 Annual Meeting of the American Academy of Orthopaedic Surgeons, March 12-16, Las Vegas, Nevada.