Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Botnar Research Centre, Windmill Road, Headington, Oxford OX3 7LD, UK.
J Bone Joint Surg Am. 2013 Aug 7;95(15):1365-72. doi: 10.2106/JBJS.L.01005.
When used for appropriate indications, unicompartmental knee replacement is associated with fewer complications, faster recovery, and better function than total knee replacement. However, joint registries demonstrate a higher revision rate for unicompartmental knee replacement. Currently, most unicompartmental knee replacements are cemented; common reasons for revision include aseptic loosening and pain. These problems could potentially be addressed by using cementless implants, with coatings designed to improve fixation. The objectives of this study were to compare the quality of fixation as well as clinical outcomes of cemented and cementless unicompartmental knee replacements at five years of follow-up.
A randomized controlled trial was established with sixty-three knees (sixty-two patients) receiving either cemented (thirty-two patients) or cementless Oxford unicompartmental knee replacements (thirty patients). Fixation was assessed with fluoroscopic radiographs aligned to the bone-implant interface at one and five years. Outcome scores, including the Oxford Knee Score, Knee Society objective and functional scores, and Tegner Activity Score, were collected preoperatively and at six months and one, two, and five years postoperatively. At each postoperative time point, these were recorded as absolute scores and change from the preoperative score.
Four patients died during the study period. There were no revisions. Mean operative time was nine minutes shorter in the cementless group (p = 0.049). At five years, there was no significant difference in any outcome measure except the Knee Society functional score and the change in the Knee Society functional score, which were significantly better in the cementless group (p = 0.003 for both). There were significantly more tibial radiolucencies in the cemented group (twenty of thirty knees versus two of twenty-seven knees; p < 0.001). There were nine complete radiolucencies in the cemented group and none in the cementless group (p = 0.01).
Cementless fixation provides improved fixation at five years compared with cemented fixation in mobile-bearing unicompartmental knee replacements, maintaining equivalent or superior clinical outcomes with a shorter operative time and no increase in complications.
Therapeutic level I. See Instructions for authors for a complete description of levels of evidence.
在适当的适应证下，单髁膝关节置换术与全膝关节置换术相比，并发症更少、恢复更快、功能更好。然而，关节登记处显示单髁膝关节置换术的翻修率更高。目前，大多数单髁膝关节置换术都是骨水泥固定的；常见的翻修原因包括无菌性松动和疼痛。这些问题可以通过使用非骨水泥植入物来解决，这些植入物采用了旨在改善固定的涂层。本研究的目的是比较骨水泥固定和非骨水泥固定的单髁膝关节置换术在五年随访时的固定质量和临床结果。
建立了一项随机对照试验，纳入 63 例（62 例患者）接受骨水泥固定（32 例）或非骨水泥 Oxford 单髁膝关节置换术（30 例）。在术后 1 年和 5 年时，使用荧光透视放射片对与骨-植入物界面对齐的固定情况进行评估。术前及术后 6 个月、1 年、2 年和 5 年收集牛津膝关节评分、膝关节学会客观和功能评分以及 Tegner 活动评分等结果评分。在每个术后时间点，这些评分均记录为绝对值和与术前评分的差值。
研究期间有 4 例患者死亡。无翻修。非骨水泥组的手术时间平均缩短了 9 分钟（p = 0.049）。在 5 年时，除膝关节学会功能评分和膝关节学会功能评分的变化外，其他任何结果测量均无显著差异，非骨水泥组的评分明显更好（p = 0.003）。骨水泥组的胫骨放射性透亮区明显多于骨水泥组（30 例中的 20 例与 27 例中的 2 例；p < 0.001）。骨水泥组有 9 例完全透亮，而骨水泥组无透亮（p = 0.01）。
与骨水泥固定相比，活动型单髁膝关节置换术中的非骨水泥固定在五年时提供了更好的固定，手术时间更短，并发症无增加，同时保持了等效或更优的临床结果。
治疗性Ⅰ级。有关证据水平的完整描述，请参见作者须知。
