Polyethylene in knee arthroplasty: A review

Area of Science:

• Biomaterials Science
• Orthopedic Surgery
• Polymer Engineering

Background:

• Polyethylene (PE) has been a standard material in knee arthroplasty since the mid-20th century.
• PE wear particles are a primary cause of osteolysis, leading to late implant failure and revision surgery.
• Advancements have yielded newer polyethylenes, including highly cross-linked variants (HXLPE), with varying properties.

Purpose of the Study:

• To evaluate the efficacy and risks of highly cross-linked polyethylene (HXLPE) in knee arthroplasty.
• To compare the wear performance of HXLPE with conventional polyethylene in knee joint replacements.
• To synthesize current laboratory and clinical evidence regarding HXLPE in knee arthroplasty.

Main Methods:

• Review of existing laboratory and clinical studies on polyethylene wear in knee arthroplasty.
• Analysis of material properties and manufacturing processes of conventional and HXLPE.
• Assessment of reported failure modes and complications associated with HXLPE use.

Main Results:

• HXLPE has demonstrated improved wear rates in hip arthroplasty, but benefits in knee arthroplasty are less pronounced.
• Limited and conflicting data exist regarding the performance of HXLPE in knee replacements.
• Potential risks of HXLPE in knee arthroplasty include tibial post fracture, locking mechanism disruption, and liner fracture.

Conclusions:

• Current evidence suggests HXLPE should be used cautiously in knee arthroplasty.
• Consideration for HXLPE may be limited to younger, active patients.
• Results from ongoing randomized trials comparing conventional and high molecular weight PE are anticipated.