Effect of acetabular liner thickness on creep resistance in HXLPE for total joint replacement: deformation rate and molecular structure

2015 Fiscal Year Final Research Report

• Project/Area Number: 25462383
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Orthopaedic surgery
• Research Institution: Tokyo Medical University
• Principal Investigator: YAMAMOTO Kengo 東京医科大学, 医学部, 教授 (10246316)
• Co-Investigator(Kenkyū-buntansha): TAKAHASHI Yasuhito 東京医科大学, 医学部, 助教 (60567668) ; SHISHIDO Takaaki 東京医科大学, 医学部, 准教授 (70266500) ; MASAOKA Toshinori 東京医科大学, 医学部, 講師 (70256270) ; TATEIWA Toshiyuki 東京医科大学, 医学部, 助教 (00424630)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 人工股関節置換術 / ポリエチレンライナー / クリープ変形速度

Outline of Final Research Achievements

The use of large femoral heads is becoming increasingly popular in total hip arthroplasty (THA). However, large femoral heads commonly necessitate to be coupled with thinner acetabular liners than the conventionally used because of the limited sizes of outer shells. The objective of this study was to experimentally clarify the size and thickness effect on the rates of compressive creep strain in conventional and vitamin E-diffused highly crosslinked, ultra-high molecular weight polyethylene (UHMWPE) acetabular liners. The rates of creep strain significantly decreased by increasing the internal diameter and thickness. Varying the component thickness contributed more largely to the creep behavior rather than the internal diameter. Our results suggest the positive mechanical advantage of using large femoral heads, but at the same time, a considerable liner thinning is not recommended for minimizing creep strain.

Free Research Field

整形外科学