Malhotra Rajesh, Kumar Vijay, Wahal Naman, Clavé Arnaud, Kennedy James A, Murray David W, Pandit Hemant
Department of Orthopaedics, All India Institute of Medical Sciences, New Delhi, India.
Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Botnar Research Centre, University of Oxford, Oxford, UK.
Indian J Orthop. 2019 Mar-Apr;53(2):289-296. doi: 10.4103/ortho.IJOrtho_172_17.
The Oxford unicompartmental knee replacement (OUKR) has achieved excellent functional outcomes and long term survivorship in many single center and single surgeon series. However, in national registries, the failure rates are up to three times higher than total knee replacement. This is at least in part due to difficulty experienced by low-volume surgeons in implanting the prosthesis accurately. A new instrumentation system (Microplasty) was introduced to help surgeons achieve better component positioning, however, it is not known whether the new instruments achieve that goal. This study investigates whether the new system achieves better component positioning and whether it improves the clinical outcomes when compared to the existing instruments.
This retrospective cohort study compared 50 consecutive OUKR implanted using the conventional Phase 3 instrumentation with 100 consecutive OUKR implanted using the new Microplasty instrumentation. Component orientation was measured on postoperative radiographs, and the percentage outside the recommended range was identified. Intraoperative data and retrospectively collected clinical data were also analyzed.
Femoral component alignment improved significantly, and there were no outliers in the Microplasty group. Although there were fewer tibial component alignment outliers with Microplasty, the difference was not significant. The intraoperative incidence of tibial recut, patient satisfaction and patient expectations was significantly better in the Microplasty group. The Oxford Knee Scores were also better with Microplasty, however, the difference was not significant.
Microplasty instrumentation helps the surgeon achieve optimal component positioning and reduces the need for tibial recut. The clinical outcomes are also better with the Microplasty instrumentation.
牛津单髁膝关节置换术（OUKR）在许多单中心和单术者系列研究中已取得了优异的功能结果和长期生存率。然而，在国家登记处，其失败率比全膝关节置换术高出两倍之多。这至少部分是由于低手术量的外科医生在精确植入假体时遇到困难。一种新的器械系统（Microplasty）被引入以帮助外科医生实现更好的假体组件定位，然而，尚不清楚新器械是否能实现这一目标。本研究调查了与现有器械相比，新系统是否能实现更好的假体组件定位以及是否能改善临床结果。
这项回顾性队列研究比较了连续50例使用传统3期器械进行的OUKR与连续100例使用新的Microplasty器械进行的OUKR。在术后X线片上测量假体组件的方向，并确定超出推荐范围的百分比。还分析了术中数据和回顾性收集的临床数据。
股骨组件的对线有显著改善，且Microplasty组中没有异常值。虽然Microplasty组胫骨组件对线的异常值较少，但差异不显著。Microplasty组胫骨再次截骨的术中发生率、患者满意度和患者期望均显著更好。Microplasty组的牛津膝关节评分也更好，然而，差异不显著。
Microplasty器械有助于外科医生实现最佳的假体组件定位，并减少胫骨再次截骨的需求。使用Microplasty器械的临床结果也更好。
