Hutt Jonathan R B, Sur Avtar, Sur Hartej, Ringrose Aine, Rickman Mark S
Department of Trauma and Orthopaedics, St George's University Hospitals NHS Foundation Trust, London, UK.
Department of Orthopaedics and Trauma, The University of Adelaide and Royal Adelaide Hospital, Adelaide, Australia.
BMC Musculoskelet Disord. 2018 May 29;19(1):172. doi: 10.1186/s12891-018-2099-2.
This prospective study evaluates outcomes and reoperation rates for unicompartmental knee arthroplasty (UKA) from a single non-designer surgeon using relatively extended criteria of degenerative changes of grade 2 or above in either or both non-operated compartments.
187 consecutive medial mobile bearing UKA implants were included after history, clinical assessment and radiological evaluation. 91 patients had extended clinical outcomes. Post-operative assessment included functional scoring with the Oxford Knee Score (OKS) and radiographic review. Survivorship curves were constructed using the life-table method, with 95% confidence intervals calculated using Rothman's equation. Separate endpoints were examined: revision for any reason and revision for confirmed loosening.
The mean follow-up was 3.5 years. The pre-operative OKS improved from a mean of 21.2 to 38.9 (Mann-Whitney U Test, p = < 0.001). Twelve Patients required further operations including 9 revisions. No patients developed deep infection and no surviving implants were loose radiographically. Survivorship at 7 years with endpoints of re-operation, revision and aseptic loosening at surgery or radiographically was 88.4% (95% CI 79.6-93.7), 93.1% (95% CI 85.5-96.9) and 97.3% (95% CI 91.2-99.2) respectively. The presence of pre-operative mild contralateral tibiofemoral or any extent of patellofemoral joint degeneration was of no consequence.
The indications for UKA are being expanded to include patients with greater deformity, more advanced disease in the patellofemoral joint and even certain features in the lateral compartment indicative of an anteromedial pattern of osteoarthritis (OA). However, much of the supporting literature remains available only from designer centres. This study represents a group of patients with what we believe to be wider indications, along with decisions to treat made on clinical grounds and radiographs alone.
This study shows comparable clinical outcomes of UKA for extended indications from a high volume, high-usage non-designer unit.
本前瞻性研究评估了由一位非特定设计器械的外科医生进行的单髁膝关节置换术（UKA）的疗效及再次手术率，该研究采用了相对宽松的标准，即非手术侧一个或两个间室的退变程度达到2级或以上。
在进行病史、临床评估和影像学评估后，纳入了187例连续的内侧活动平台UKA植入病例。91例患者获得了延长的临床疗效。术后评估包括使用牛津膝关节评分（OKS）进行功能评分和影像学复查。采用寿命表法构建生存曲线，使用罗斯曼公式计算95%置信区间。分别检查了不同的终点：因任何原因进行的翻修和因证实松动而进行的翻修。
平均随访时间为3.5年。术前OKS评分从平均21.2分提高到38.9分（曼-惠特尼U检验，p＜0.001）。12例患者需要进一步手术，其中9例为翻修手术。没有患者发生深部感染，影像学检查也未发现存活的植入物松动。以再次手术、翻修以及手术中或影像学检查发现无菌性松动为终点的7年生存率分别为88.4%（95%置信区间79.6 - 93.7）、93.1%（95%置信区间85.5 - 96.9）和97.3%（95%置信区间91.2 - 99.2）。术前对侧胫股关节轻度退变或髌股关节任何程度的退变均无影响。
UKA的适应证正在扩大，包括畸形更严重、髌股关节疾病更晚期甚至外侧间室具有某些提示前内侧型骨关节炎（OA）特征的患者。然而，许多支持性文献仅来自特定设计器械的中心。本研究代表了一组我们认为适应证更广泛的患者，并且仅基于临床情况和X线片做出治疗决策。
本研究表明，来自一个高手术量、高使用量的非特定设计器械单位的UKA，对于扩大适应证具有相当的临床疗效。
