Long-term outcomes with a partial neck-preserving cementless short stem in primary total hip arthroplasty for young patients: a single center first one hundred cases

Purpose

This study aimed to assess the long-term results of THA patients who received a cementless short stem regarding clinical outcomes, bone changes, complications, and incidence of femoral revision.

Methods

A retrospective evaluation of the first 100 THA employing a type 2B cementless stem (Mini hip stem, Corin, Cirencester, United Kingdom) by the same surgeon at one institution. We only include patients with 18 years or more, and with a minimum follow up of 8 years. Patient’s Harris hip score (HHS), the University of California, Los Angeles activity score (UCLA), and radiographic outcomes were evaluated.

Results

A total of 100 primary hip arthroplasties with Mini Hip stems were performed on 84 patients, with an average age of 47 years old. The median follow-up was 120 months (IQR 57.5-136.5), with 47 patients having a minimum 10-year follow-up. The patient’s HHS improved significantly (p < 0.001) and UCLA’s score was 7 (SD 1.7) at the final follow-up. Only one patient suffered an intraoperative lateral cortical perforation, which was treated on the same day with revision of the short stem to a conventional metaphysodiaphyseal fixation stem. Three incomplete fractures of the calcar occurred intraoperative, of which only one required wire cerclage and unloading partial during the 30 days after surgery. No osteolysis, radiolucency, thigh pain, periprosthetic or ceramic fractures were observed. Only 6% hips experience squeaking without the need for revision. Two acetabular components were revised early, but no stem failures were recorded, yielding an incidence density rate of 0% (95% CI 0-0.05%) over 10 years.

Conclusion

This study showed that the MiniHip short stem is a reliable option for THA in younger patients, with a high implant survival rate and excellent functional outcomes over the long term.