Battle of the titans: Survivorship analysis of the 3 most common types of uncemented femoral stems used across national registries

Martin S Davey; Tom R Doyle; Evelyn Murphy; Christopher Fenelon; Colin G Murphy; Adrian J Cassar-Gheiti

doi:10.1016/j.jor.2023.07.010

Battle of the titans: Survivorship analysis of the 3 most common types of uncemented femoral stems used across national registries

J Orthop. 2023 Jul 21:43:41-47. doi: 10.1016/j.jor.2023.07.010. eCollection 2023 Sep.

Authors

Martin S Davey^{1

2}, Tom R Doyle², Evelyn Murphy¹, Christopher Fenelon¹, Colin G Murphy^{2

3}, Adrian J Cassar-Gheiti⁴

Affiliations

¹ Royal College of Surgeons in Ireland, Dublin, Ireland.
² Galway University Hospitals, Galway, Ireland.
³ University of Galway, Galway, Ireland.
⁴ National Orthopaedic Hospital Cappagh, Dublin, Ireland.

PMID: 37564704
PMCID: PMC10409998 (available on 2024-09-01)
DOI: 10.1016/j.jor.2023.07.010

Abstract

Background: Although many institutions utilize uncemented stems as routine in performing total hip arthroplasty (THA), many surgeons continue to rely on outcomes reported in the literature in the form of small cohorts and patient series when analyzing survivorship for specific implants. The purpose of this study was to identify and analyze the survivorship of the 3 most common uncemented stem types (as opposed to brands) used across multiple national joint registries.

Methods: A review of data available from all national joint registries was carried out in July 2022. Analysis of each individual registry and classified uncemented implants into the seven different uncemented stem types. The 3 most common stem types were identified, and average cumulative revision rates calculated. Metal on metal bearings surface implants were excluded from this study due to high revision rates across all implant types.

Results: Our detailed review identified 6 out of 13 (NJR, AOANJRR, LROI, EPRD, MARCQI and the NZJR) international registries reporting implant specific survivorship on uncemented femoral stems; including 960,328 uncemented stems across all registries. The most common type of stem used was type 3c, accounting for 61% (583,724), followed by type 1 stems with 23% (217,897) and type 2 stems with 8% (79,257). Cumulative revision rates at 13 years follow-up for these stems ranged from 6.9% to 7.9%.

Conclusion: Although all stem types have comparable revision rates across all registries, the most common uncemented stem reported was the type 3c, tapered rectangular fully coated stem. Furthermore, out of all type 3c, the Müller design philosophy with full hydroxyapatite coating seems to be the most sought after worldwide. In this study we can conclude, thus far, that there does not appear to clinical or statistical differences in revision rates between the different stem types.

Level of evidence: III.

Publication types

Review