Osaka, Japan: A hip replacement is challenging, but needing another one is worse. Surgeons at Osaka Metropolitan University have studied two types of hip replacement stems. Their research aims to improve long-term outcomes, enhance quality of life, and reduce repeat surgeries.
Their study was published in The Bone & Joint Journal on June 1.The hip joint connects the thighbone to the pelvis, supporting body weight and movement. Total hip replacement involves replacing a damaged hip joint with an implant to relieve pain and stiffness.
“After surgery, lower bone density around the femur can lead to fractures and loose joints, needing another hip surgery,” said Yohei Ohyama, lead author and surgeon at Osaka Metropolitan University.
The team analyzed bone density changes and stem contact with the femur for two types of hip replacement stems: traditional full hydroxyapatite (HA)-coated stems and new shorter HA-coated stems designed for minimally invasive surgery.
The study involved 66 patients: 36 with traditional HA stems, and 30 with new HA stems. Bone density was measured using x-rays one and two years after surgery, and a 3D system assessed stem contact with the bone.
Results showed that the new HA stems had larger contact areas with the femur. In contrast, after two years, traditional HA stems increased bone density in the upper inner femur.
The study highlights the differences in fixation and bone density preservation between the two stems. New HA stems have better contact areas, but traditional HA stems preserve bone density better over time.
These findings help surgeons choose the best stem for hip replacements to improve patient outcomes and implant longevity.
Ohyama said, “Total hip replacement enhances life and extends healthy lifespans. We hope our findings will make artificial joints a lifetime solution.”
Journal Reference :
- Yohei Ohyama, Yukihide Minoda et al., Contact states with femoral cortical bone and periprosthetic bone mineral density changes differ between traditional and newly introduced fully hydroxyapatite-coated stems. The Bone & Joint Journal. DOI: 10.1302/0301-620X.106B6.BJJ-2023-1157.R2.