Scott E, et al. Paper 56. Presented at: Pediatric Orthopaedic Society of North America Annual Meeting; May 13, 2020 (virtual meeting).
Long-term survival after hip dysplasia similar with open, closed reduction techniques
Patients with developmental hip dysplasia who underwent either closed reduction or open reduction and Salter innominate pelvic osteotomy achieved a long-term survival time free of total hip arthroplasty, researchers of this study found.
However, THA and osteoarthritis were more likely after use of the closed reduction technique, according to study results that Stuart L. Weinstein, MD, of University of Iowa, in Iowa City, Iowa, presented at the Pediatric Orthopaedic Society of North America Annual Meeting.
“This unique comparative study showed that both treatments likely improved total hip-free survival relative to the actual history for dislocated hips after the age of 18 months, but neither prevented the eventual development of osteoarthritis and the need for total hip arthroplasty in the majority of patients,” Weinstein said.
Researchers included 58 hips in 45 pediatric patients who had their dislocated hips treated with open reduction from 1933 to 1942, and 78 hips in 58 patients who had their dislocated hips treated with open reduction and innominate pelvic osteotomy from 1958 to 1965. Physicians at two institutions performed the reductions.
All patients were followed for a minimum of 40 years or to the point of THA. The patients all met the Thomas inclusion criteria for having undergone hip reduction only when they were aged 18 to 60 months.
“At 48-year follow-up, a greater percentage of patients in the closed reduction group eventually underwent total hip arthroplasty, but note that the time to total hip replacement was similar in both groups,” Weinstein said.
In all, 29 hips treated with closed reduction and 44 hips treated with open reduction and innominate osteotomy had a survival time of 48 years.
The multivariate regression analysis done to estimate patients’ odds of undergoing THA, given various risk factors, showed the probability for THA was 20% higher in unilateral hips treated with closed reduction regardless of the patient’s age at the time of reduction. Researchers noted in the abstract the probability for THA was significantly lower among patients whose dislocated bilateral hips were treated with open reduction and innominate osteotomy.
The indication for additional procedures was reported for 17% of patients in the closed reduction group and 22% of patients in the open reduction and innominate osteotomy group, according to the results.
Weinstein said the small sample size was a weakness of the study, among other factors.
Furthermore, “Neither series described here represents the independent effect of either treatment as secondary procedures were performed after the index reduction in both cohorts and elements of both treatment protocols changed over time and differ from modern practices,” he said.