# 1000 collared cementless femoral stems: periprosthetic fracture rates in 500 THA versus 500 hemiarthroplasties

## TL;DR

This study compares fracture rates using a specific type of hip implant in two patient groups, finding similar risks and better survival in elective surgery patients.

## Contribution

The study provides evidence that collared cementless femoral stems are safe for hemiarthroplasty in hip fracture patients.

## Key findings

- Intra-operative periprosthetic fracture rates were 1.4% in THA and 3% in NOF groups.
- Early postoperative fracture rates were 0.6% in THA and 0.8% in NOF groups.
- 90-day mortality was 0% in THA patients but 8.8% in NOF patients.

## Abstract

This study investigates the claim that the majority of elderly patients undergoing elective total hip arthroplasty (THA) that would routinely be treated with a collared cementless stem are just one fall away from a neck of femur fracture that would then commit them to a cemented femoral prosthesis in many other institutions. This study aims to compare the incidence of intra-operative periprosthetic fracture (PPF) and early postoperative PPF using a cementless collared femoral stem between 500 consecutive elective total hip arthroplasty (THA) patients and 500 consecutive neck of femur (NOF) fracture patients treated with a hemiarthroplasty.

This was a single-institution retrospective cohort study between August 2015 and December 2023 assessing 500 consecutive NOF fractures and 500 consecutive elective THAs treated with a single brand of collared cementless femoral stem. The primary outcome measure was intra-operative PPF. Secondary outcome measures included early PPF, defined as PPF within 90 days of initial surgery and 90-day mortality.

The mean age in the THA group was 66 (range 32–94) with 246/500 (49.2%) patients being female. In the NOF group, the mean age was 80 (range 45–102) with 350/500 (70%) of patients being female. In the THA group, seven (1.4%) of patients sustained an intra-operative fracture compared with 15 (3%) patients in the NOF group (p = 0.09). There were three (0.6%) early PPFs in the elective group compared to four (0.8%) in the NOF group (p = 0.7). The 90-day mortality was zero in the elective group and 8.8% in the NOF group. None of the NOF patients with an intra-operative fracture died at the time of follow-up.

Collared cementless femoral stems are safe for use in hemiarthroplasty for hip fracture, especially in an institution that performs cementless HA as standard practice for all hip fractures requiring hemiarthroplasty.