Nodzo Scott R, Esposito Christina I, Potter Hollis G, Ranawat Chitranjan S, Wright Timothy M, Padgett Douglas E
Department of Orthopaedics, Hospital for Special Surgery, New York, New York.
Department of Biomechanics, Hospital for Special Surgery, New York, New York.
J Arthroplasty. 2017 May;32(5):1647-1653. doi: 10.1016/j.arth.2016.11.046. Epub 2016 Dec 8.
The severity and location of adverse local tissue reaction (ALTR) seen in metal-on-polyethylene total hip arthroplasty (THA) is not well described.
We retrospectively reviewed the records of patients who underwent a revision THA using our biomechanics database. We included all patients who underwent revision surgery for the diagnosis of ALTR with THA implants that had modularity solely at the head-neck junction and excluded patients with implant modularity at sites other than the head-neck junction. Magnetic resonance imaging (MRI) was evaluated by a fellowship-trained radiologist who specializes in evaluating metal artifact reducing MRI sequences to quantify the ALTR lesions. Histology was evaluated for findings of ALTR using the Campbell score.
We identified 11 patients in the database. Eight patients had an MRI ALTR grade of severe and 7 did based on the histology score. The mean synovial volume was 218,658 mm (range 23,461-451,435 mm) with a mean maximal synovial thickness of 15.3 mm (range 3-34.3 mm). A disruptive infiltration of the abductors due to pseudocapsule invasion was seen in 67% of the patients with 3 not having abductor involvement. Mean preoperative cobalt and chromium levels were 5.4 ppb (range 1-12.3 ppb) and 1.1 ppb (range 0.6-2.4 ppb), respectively.
Patients with ALTR from head-neck junction corrosion in metal-on-polyethylene THA may present with large pseudotumors that have previously been under appreciated. Mean preoperative serum cobalt and chromium ion levels remained relatively low, and MRI was an effective way to characterize the size and location of these lesions.
金属对聚乙烯全髋关节置换术（THA）中出现的局部组织不良反应（ALTR）的严重程度和位置尚未得到充分描述。
我们使用生物力学数据库回顾性分析了接受翻修THA患者的记录。我们纳入了所有因ALTR诊断而接受翻修手术的患者，这些患者的THA植入物仅在头颈交界处具有模块化设计，排除了在头颈交界处以外部位具有植入物模块化的患者。由一位专门评估减少金属伪影的MRI序列以量化ALTR病变的专科放射科医生对磁共振成像（MRI）进行评估。使用坎贝尔评分对组织学进行评估以确定ALTR的发现。
我们在数据库中识别出11例患者。8例患者的MRI显示ALTR分级为重度，7例基于组织学评分也为重度。滑膜平均体积为218,658立方毫米（范围为23,461 - 451,435立方毫米），滑膜最大平均厚度为15.3毫米（范围为3 - 34.3毫米）。67%的患者可见因假包膜侵犯导致的外展肌破坏浸润，3例患者外展肌未受累。术前钴和铬的平均水平分别为5.4 ppb（范围为1 - 12.3 ppb）和1.1 ppb（范围为0.6 - 2.4 ppb）。
金属对聚乙烯THA中因头颈交界处腐蚀导致ALTR的患者可能出现以前未被充分认识的大假肿瘤。术前血清钴和铬离子的平均水平仍然相对较低，MRI是表征这些病变大小和位置的有效方法。
