Gaba Sahil, Wahal Naman, Gautam Deepak, Pandit Hemant, Kumar Vijay, Malhotra Rajesh
Department of Orthopaedics, All India Institute of Medical Sciences (AIIMS), New Delhi, India.
Orthopaedics and Honorary Consultant, Chapel Allerton Hospital, University of Leeds, UK.
Arch Bone Jt Surg. 2018 Jul;6(4):301-311.
Oxford medial unicompartmental knee replacement (UKR) is indicated in patients with anteromedial osteoarthritis (AMOA) of the knee. Microplasty (MP) instrumentation was introduced in 2012 as an improvement over phase 3 instrumentation. Advantages of this instrumentation include conservative tibial cut, decreased tibial re-cut rate and improved component alignment. We report the results of UKR with the new instrumentation in a consecutive series with a minimum follow-up of 2 years.
A prospective study of 115 cemented medial Oxford UKRs implanted in 89 patients was done. Post-operative alignment of the tibial and femoral components was analysed. Patient reported outcome measures were recorded using Oxford Knee Score (OKS) and the American Knee Society Score (KSS). Tegner Activity Scale (TAS) was used to record the activity level.
115 consecutive medial Oxford UKRs were studied. All patients were followed up annually in this prospective ethically approved study. The mean follow-up was 36 months and the minimum follow-up was 25 months. No patient died and none were lost to follow-up. At the final follow-up, the average OKS of the cohort was 39.5 (SD: 5.7). 91.2 % of the patients had good or excellent OKS with only 3.5 % reporting poor OKS. The overall limb alignment was 4.8 varus (0 - 14 varus). Tibia was recut in 5.2 % of cases. Median bearing size was 3 (range: 3 to 6). There was one case of bearing dislocation and one case of aseptic tibial loosening.
This is the first study to report results of MP instrumentation at a minimum follow-up of 2 years. Our study indicates that the new instrumentation results in reliable and accurate implantation of femoral and tibial components in majority of the cases, with a decrease in number of alignment outliers, and also a reduced rate of bearing dislocation.
牛津内侧单髁膝关节置换术（UKR）适用于膝关节前内侧骨关节炎（AMOA）患者。微整形（MP）器械于2012年推出，是对第三代器械的改进。该器械的优点包括胫骨截骨保守、胫骨再次截骨率降低以及部件对线改善。我们报告了使用这种新器械进行UKR的连续系列病例结果，随访时间至少为2年。
对89例患者植入的115例骨水泥固定的内侧牛津UKR进行了前瞻性研究。分析了胫骨和股骨部件的术后对线情况。使用牛津膝关节评分（OKS）和美国膝关节协会评分（KSS）记录患者报告的结局指标。使用 Tegner 活动量表（TAS）记录活动水平。
对115例连续的内侧牛津UKR进行了研究。在这项经伦理批准的前瞻性研究中，所有患者每年接受随访。平均随访时间为36个月，最短随访时间为25个月。无患者死亡，无一例失访。在最后随访时，该队列的平均OKS为39.5（标准差：5.7）。91.2%的患者OKS为良好或优秀，只有3.5%的患者报告OKS较差。整体肢体对线为4.8°内翻（0 - 14°内翻）。5.2%的病例进行了胫骨再次截骨。中位轴承尺寸为3（范围：3至6）。有1例轴承脱位和1例无菌性胫骨松动。
这是第一项报告MP器械至少随访2年结果的研究。我们的研究表明，这种新器械在大多数情况下能实现股骨和胫骨部件的可靠、准确植入，减少了对线异常的数量，也降低了轴承脱位率。
