Marappa-Ganeshan Raghavendra, Sim Francis, Sidhom Sameh, Chakrabarty Gautam, Pandit Hemant G, van Duren Bernard H
Calderdale and Huddersfield Hospitals Trust, Huddersfield, England UK.
University of Huddersfield, Huddersfield, England UK.
Indian J Orthop. 2020 Sep 5;54(6):863-867. doi: 10.1007/s43465-020-00203-6. eCollection 2020 Nov.
Accurately predicting implant size for hemiarthroplasties offers an important contribution to theatre efficiency and patients' intraoperative care. However, pre-operative sizing using templating of implants in hip fracture patients requiring a hemiarthroplasty is often difficult due to non-standard radiographs, absence of a calibration marker, poor marker placement, variable patient position, and in many institutions a lack of templating facilities. In patients who have previously undergone a hemiarthroplasty on the contralateral side, surgeons can use the contralateral implant size for pre-operative planning purposes. However, the accuracy of doing this has not previously been reported. The aim of this study was to investigate the reliability of using an in situ contralateral implant as a predictor of implant size on the contralateral side.
A retrospective review of our local neck of femur fracture (NOF) database was undertaken to identify patients who had bilateral hip hemiarthroplasty. Operative records were reviewed to establish the size of prostheses used at operation. Correlation, agreement, and reliability analysis were performed using the least squares, Bland-Altman plot, and intra-class correlation coefficient (ICC) methods, respectively.
Operative records were identified for 45 patients who had bilateral hemiarthroplasties. There was a difference in implant size used in 58% of cases. Of these 77% required a larger implant on the right. Implant sizes were within 1 mm of the contralateral side in 78% and within 2 mm in 91% of patients. However, in 9% of patients, there was a discrepancy greater than 2 mm with some cases having up to 6 mm discrepancy. Correlation coefficient was 0.83 and the ICC 0.90.
The findings in this study indicated that using the size of a contralateral implant can be used as a reliable indicator of head size in cases of bilateral hemiarthroplasty. However, the surgeon should remain cautious as there is a one in ten chance of there being a 3 mm or more difference in implant size.
准确预测半髋关节置换术的植入物尺寸对手术效率和患者术中护理具有重要意义。然而，对于需要进行半髋关节置换术的髋部骨折患者，由于X线片不标准、缺乏校准标记、标记放置不佳、患者体位多变，以及在许多机构中缺乏模板设施，术前通过模板测量植入物尺寸往往很困难。对于先前在对侧进行过半髋关节置换术的患者，外科医生可以将对侧植入物尺寸用于术前规划。然而，此前尚未报道这样做的准确性。本研究的目的是调查使用原位对侧植入物作为对侧植入物尺寸预测指标的可靠性。
对我们当地的股骨颈骨折（NOF）数据库进行回顾性研究，以确定接受双侧髋关节半髋关节置换术的患者。查阅手术记录以确定手术中使用的假体尺寸。分别使用最小二乘法、Bland-Altman图和组内相关系数（ICC）方法进行相关性、一致性和可靠性分析。
确定了45例接受双侧半髋关节置换术患者的手术记录。58%的病例中使用的植入物尺寸存在差异。其中77%的患者右侧需要更大的植入物。78%的患者植入物尺寸与对侧相差在1毫米以内，91%的患者相差在2毫米以内。然而，9%的患者差异大于2毫米，有些病例差异高达6毫米。相关系数为0.83，ICC为0.90。
本研究结果表明，在双侧半髋关节置换术的情况下，使用对侧植入物的尺寸可作为头部尺寸的可靠指标。然而，外科医生应保持谨慎，因为植入物尺寸相差3毫米或更多的几率为十分之一。
