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Published on: June 3, 2019
Is there any difference between tapered titanium stems with similar geometry and hydroxyapatite coating?
G Cinotti1, G Mazzotta2, F Romana Ripani3
1Department of Anatomical, Histological, Forensic Medicine and Orthopaedics Sciences, University "La Sapienza", Piazzale Aldo Moro, 5 00185, Rome, Italy. md3581@mclink.it.
Hydroxyapatite-coated tapered stems, despite similar appearances, show significant geometric differences. These variations mean orthopedic surgeons must carefully select stems based on patient femoral morphology for optimal outcomes.
Area of Science:
- Orthopedic Surgery
- Biomedical Engineering
- Materials Science
Background:
- Several tapered hip stems with hydroxyapatite (HA) coating are available.
- Their similar appearance and coating suggest interchangeability in cementless hip arthroplasty.
Purpose of the Study:
- To analyze geometric features of five HA-coated tapered stems.
- To determine if these stems exhibit similar designs for interchangeable clinical use.
Main Methods:
- Measurements included stem length, coronal/sagittal diameters, shoulder length, and metadiaphyseal angle.
- Flare and tapered indices were calculated to quantify stem geometry.
Main Results:
- Significant differences were observed in flare index, tapered index, shoulder length, and metadiaphyseal angle among different stem brands.
- Proximal diameters varied considerably between brands and sizes.
Conclusions:
- Tapered stems with HA coating, despite looking similar, possess distinct geometric characteristics.
- These differences can impact clinical performance, necessitating patient-specific stem selection based on femoral anatomy.
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