Tibial Baseplate Fracture after Mobile-Bearing Total Knee Arthroplasty-A Case Report

低接觸壓力脛骨可動式聚乙烯襯墊人工膝關節術後脛骨元件疲乏性斷裂之病例報告

洪俊青(Chun-Ching Hung)；黃昌宏(Chang-Hung Huang)；高鴻展(Hung-Chan Kao)；盧永昌(Yung-Chang Lu)；張定國(Ting-Kuo Chang)；黃俊雄(Chun-Hsiung Huang)

tibial baseplate ； fracture ； mobile bearing ； total knee prosthesis

Journal of Orthopaedic Surgery Taiwan

27卷2期（2010 / 06 / 01）

91 - 96

英文

Metallic tibial baseplate fracture is an infrequent complication after total knee arthroplasty (TKA). From our clinical experience and literature review, baseplate fractures were occasionally found in fixed bearing knees, but no case was found in mobile bearing knees so far. We present a case of baseplate fracture in Low-Contact-Stress Meniscal-Bearing total knee prosthesis after twelve-years of implantation. Clinical examination, retrieval analysis, scanning electron microscopy (SEM) and Energy Dispersive Spectrometer (EDS) were comprehensively applied to speculate the possible factors resulting in metallic fracture. The tibial baseplate was fractured along the edge of medial track rail of meniscal bearing. Fatigue striations were observed near the posteromedial portion of the baseplate by SEM observation, indicating fracture initiation started surrounding the track rail. No material defects were detected by EDS.