In revision to THR, patients with surface replacement fared better than patients with THR
BARCELONA, Spain — Total surface replacement may still be a viable hip arthroplasty option in young, active patients based on how well it fared in a study when it was revised to total hip replacement vs. primary THR that was revised to THR, according to a presenter at the EFORT Annual Congress.
Orthopedic trainee Benjamin P. Kent, who is at Royal Cornwall Hospital in the United Kingdom, presented results of a case-controlled study of 129 patients with primary resurfaced hips who underwent a revision to THR and were compared to an age- and sex-matched control group of 129 patients who underwent primary THR that was revised to THR. All the patients were identified from the hospital’s electronic database. Based on their power analysis, investigators sought to find a minimally clinically significant difference of five points on the Oxford hip score (OHS), Kent said.
“Despite the intuitive promises of resurfacing as a bone-preserving procedure, we were unaware of any studies that examined whether resurfacing patients have an easier, less dramatic revision and whether their post-revision functional outcome is better than those who had a standard prosthesis. This study set out to answer these questions,” Kent said.
According to the results he presented, the demographics for both groups were not different. However, at the mean follow-up of 7 years, “the Oxford hip score is significantly different in the resurfacing group with a seven-point advantage over those who have been revised from a standard stem,” he said.
The OHS for the patients with revised resurfacings was 36.78 compared to 29.70 for the control group “with a significant P value,” according to Kent.
Revisions among patients undergoing revisions for a resurfaced hip vs. THR were associated with a statistically significantly shorter length of stay, he noted.
Kent noted a weakness of the study was blood loss and transfusion data for both groups was incomplete because some of this information was lost when his hospital system updated its electronic records. However, from the information on hand, he said, “obviously there is a significant difference between 4% of the resurfacing revisions and the 26% of the total hip replacements that required transfusions postoperatively.”
“Our study shows, therefore, that there is less blood loss, there’s a shorter length of stay and better function in patients undergoing revision of resurfacing as opposed to revision of a standard stemmed prosthesis,” Kent said. – by Susan M. Rapp
Kent BP, et al. Paper 2452. Presented at: EFORT Annual Congress; May 30-June 1, 2018; Barcelona, Spain.
Disclosure: Kent reports no relevant financial disclosures.