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United Orthopedic Corporation Announces FDA Clearance for Vitamin E Highly Cross-Linked Polyethylene Hip Liner

E-XPETM Designed to Provide Wear Resistance with Reduced Risk of Oxidation is Now Available in Both Knee Inserts and Hip Liners

IRVINE, Calif., November 27, 2018 – United Orthopedic Corporation, a leading international designer, manufacturer, and distributor of innovative orthopedic implants and instruments, today announced that the U.S. Food and Drug Administration has cleared its vitamin E highly cross-linked polyethylene (E-XPETM) hip liner. The E-XPETM is the new generation of highly cross-linked polyethylene blended with vitamin E to enhance wear resistance without compromising oxidative stability and mechanical properties.

“Oxidation continues to be a concern for surgeons. Over time, wear of conventional polyethylene can generate debris in the joint, triggering local inflammation that results in bone loss which is one of the biggest causes of late-term failure in hip and knee replacements,” said Calvin Lin, President of United Orthopedic Corporation USA. “Clearance of our E-XPETM, a vitamin E highly cross-linked polyethylene, provides surgeons with an alternative implant for their patient. Our vertically integrated manufacturing process affords us the flexibility to design, manufacture and distribute implants or instruments that address many of the most significant needs in the orthopedic industry.”

Vitamin E is an effective biological antioxidant which helps prevent the oxidative degradation of cell membrane phospholipids. When added to ultra-high molecular weight polyethylene (“UHMWPE”), vitamin E performs a similar role by helping to prevent oxidation of the polyethylene chains.1 Vitamin E -stabilized UHMWPE is a biocompatible material with good mechanical, wear, and oxidative proprieties. Results from accelerated aging tests show that E-XPETM inserts and liners exhibited a 60 percent and 75 percent reduction, respectively, in gravimetric wear2. E-XPETM material provides greater strength in comparison to re-melted highly crosslinked polyethylene while maintaining oxidation resistance as demonstrated in mechanical tests.

An estimated 4.7 million Americans have undergone total knee arthroplasty (“TKA”) and 2.5 million have undergone total hip arthroplasty (“THA”).The prevalence of THA rises to nearly 6 percent by 80 years of age. The prevalence of TKA rises to nearly 10 percent by 80 years of age.3

About United Orthopedic Corporation

United Orthopedic Corporation is a leading international designer, manufacturer, and distributor of innovative orthopedic implants and instrument sets.

The company offers clinically proven solutions used in primary and revision total hip/knee replacement in addition to oncology applications. The company has implemented and maintains Quality Management Systems compliant with ISO 13485, FDA and CE requirements. To learn more visit

Media Contact:

Tiffany Lin
Tel: +1 949-328-3366

1 Gigante A, Bottegoni C, Ragone V, Banci L. Effectiveness of Vitamin-E-Doped Polyethylene in Joint Replacement: A Literature Review. J Funct Biomater 2015; 6(3):889-900.

2 Chang TW, Cheng YW, Lu CK, Liau JJ. Is Highly Cross Linked UHMWPE Blended with Vitamin E a Viable Reduction Wear in TKA? Presented at Orthopaedic Research Society, 2017, San Diego, CA.

3 Maradit Kremers H, Larson DR, Crowson CS, Kremers WK, Washington RE, Steiner CA et al. Prevalence of Total Hip and Knee Replacement in the United States. J Bone Joint Surg Am 2015; 97(17):1386-97.

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