Patterns and Risk Factors of Aseptic Loosening in a Hydroxyapatite-Coated Cementless Quadrangular Taper Femoral Stem: A Single-Center Cohort Study
Year: 2026
Type: article
Study design: Observational Study
Abstract: Background: There have been several reports of metaphyseal debonding of hydroxyapatite (HA)-coated cementless quadrangular taper femoral stems leading to revisions for aseptic loosening. This study aimed to assess the characteristics and risk factors of this type of revision. Methods: A single-center cohort of total hip arthroplasty patients who received a cementless HA-coated Corail stem between 2006-2023 was identified. Cox proportional hazard models were used to estimate the hazard ratios (HRs) and confidence intervals (CIs) of the association between implant/patient characteristics and revision for aseptic loosening. Dorr type and canal fill was assessed for all patients undergoing revision. Results: The study identified 3876 patients leading to 27 aseptic loosening revisions and 91 other revisions. Stem size <10 was associated with aseptic loosening, HR = 9.1 (95% CI 3.4-24.2). Taller patients, metal-on-metal bearings, and collarless stems were all associated with higher risk. Half of patients with aseptic loosening had Dorr type A femurs and half had undersized stems. Initial radiographs showed little to no radiolucency for these patients. Radiolucency increased after several postoperative years. Only 20% of patients with other reasons for revision had undersized stems and these patients exhibited less radiolucency. Conclusions: Smaller, undersized HA-coated cementless quadrangular taper stems appear to be at significantly increased risk of aseptic loosening in midterm follow-up. Surgeons using quadrangle tapered cementless stems should be cautious when broaching suggests a stem size smaller than preoperative templating recommended, especially in patients with narrow femoral canals and should consider using a collar whenever possible with this stem design.
Source: Arthroplasty Today
Language: English
Subfield: Surgery
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $2,500
OpenAlex ID: W7204924300