Early Fracture of a Vitamin-E-Infused, Highly Cross-Linked Polyethylene Liner After Total Hip Arthroplasty: A Case Report

Area of Science:

• Biomaterials Science
• Orthopedic Surgery
• Materials Engineering

Background:

• Highly cross-linked ultra-high molecular weight polyethylene (HXLPE) is widely used in acetabular liners.
• Conventional HXLPE production involves a remelting process that reduces initial fracture toughness but enhances oxidative stability.
• Vitamin-E-infused HXLPE aims to improve mechanical properties by avoiding the remelting step.

Purpose of the Study:

• To report a case of early, atraumatic failure of a vitamin-E-infused HXLPE acetabular liner.
• To discuss the implications of this failure mode in the context of HXLPE manufacturing processes.

Main Methods:

• A case report detailing the clinical presentation and outcome of a seventy-one-year-old woman with a fractured vitamin-E-infused HXLPE acetabular liner.
• Review of the manufacturing process and material properties of vitamin-E-infused HXLPE compared to conventional HXLPE.

Main Results:

• The vitamin-E-infused HXLPE acetabular liner fractured without any history of trauma less than twelve months post-implantation.
• The fracture occurred despite acceptable component positioning, suggesting a material-related failure.

Conclusions:

• While avoiding the remelting process preserves initial fracture toughness, vitamin-E-infused HXLPE is not immune to catastrophic failure.
• This case underscores the need for continued investigation into the long-term performance and failure mechanisms of novel bearing materials in total hip arthroplasty.