Multicentre outcomes of total hip arthroplasty using a novel collared cementless femoral stem.

Aims: Recent years have seen increased interest in tissue-sparing approaches for total hip arthroplasty (THA), which has led to innovations in implant design. Short cementless femoral components have gained traction, and the inclusion of a medial calcar collar to improve stability may offset the risk of fracture. The aim of this current study is to report short-term outcomes and survivorship for a novel design of femoral component across four non-designer centres. Methods: All patients undergoing primary THA across four centres from July 2020 to January 2025 were eligible for inclusion. Data were collected prospectively in a national arthroplasty register, with planned routine follow-up at six months and two years. Patient-reported outcome measures were assessed using the Oxford Hip Score (OHS) and EuroQol five-dimension questionnaire (EQ-5D) score. Results: A total of 517 components in 489 patients were included in the dataset: three patients (0.6%) died by final follow-up, and of the remaining 514 components, 512 components (99.6%) remain in situ. For the two patients (0.4%) undergoing revision surgery, indications for revision were periprosthetic fracture (PPF) and large postoperative haematoma. PPF affected four patients (0.8%) in total: two intraoperative events were managed with cables, and one Vancouver C fracture was managed with plate and screw fixation. The mean preoperative OHS was 17 (95% CI 16.3 to 17.7) with a mean postoperative score of 40.7 (95% CI 39.7 to 41.5), and mean preoperative EQ-5D score was 0.36 (95% CI 0.34 to 0.38), with a mean postoperative score of 0.80 (95% CI 0.78 to 0.82). Conclusion: This novel femoral component demonstrates excellent functional outcomes which are reproducible across multiple surgeons in non-designer centres, with low rates of revision surgery and PPF.