A team of researchers from Seoul, South Korea set out to determine if long term implant survivorship in young patients is better for those who receive cementless femoral stems or cemented stems. Their work, “Minimum 30-Year Results of Bilaterally Implanted Cemented and Cementless Total Hip Arthroplasty in Patients Younger Than 50 Years,” appears in the November 18, 2022, edition of The Journal of Arthroplasty.
Co-author Young-Hoo Kim, M.D. commented to OTW, “We wanted to study this in order to verify whether we need cemented stems anymore.”
In order to quantify radiographic differences between cemented and cementless, specifically signs of loosening or osteolysis, the authors looked at 106 patients who had bilateral total hip arthroplasty (THA) with a cemented stem in one hip and a cementless stem in the other. They also wanted to determine if there were fewer complications in the cementless stem than in the cemented stem.
The study group consisted of 78 men and 28 women (mean age was 47 years), with an average follow-up of 31 years. The team randomized patients to receive either the cementless stem (Profile stem; DePuy) or the cemented THA (Charnley Elite-Plus stem [Ortron 90]; DePuy). They used a computer program to equally assign all patients to receive one type of component in one hip and the other type in the other hip. A cementless Duraloc 100 or 1200 series acetabular component (DePuy) was used in all hips (both groups). One author performed all of the surgeries using a posterolateral approach.
“We found that the survivorship of cemented and cementless stems were similar,” said Dr. Kim to OTW.
Indeed, they were very similar with preop mean Harris Hip Scores of 43 points for the cemented group versus 44 points for the cementless group and final follow-up scores of 90 points for the cemented group versus 91 points for the cementless group.
Implant survival was also similar in the two groups, with the Kaplan-Meier survival analysis in the cemented group (revision at 31 years as the end point) showed 57% survival for the acetabular component and 95% survival for the femoral component. In the cementless group, the Kaplan-Meier survival analysis (revision at 31 years as the end point) showed 55% survival for the acetabular component and 96% survival for the femoral component. Five femoral components in the cemented group and four femoral components in the cementless group were revised.
When OTW asked Dr. Kim about any concerns regarding these procedures in younger patients, he noted, “The bearing surface is an issue. It would be helpful to reduce osteolysis in a long-term ceramic-on-ceramic or ceramic-on-highly crosslinked polyethylene. More work needs to be done on stress shielding-related bone resorption in both stems.”
