Chia Zi-Yang, Pang Hee-Nee, Tan Mann-Hong, Yeo Seng-Jin
Department of Orthopaedic Surgery, Singapore General Hospital, 20 College Road, Academia, Level 4, Singapore 169865, Singapore.
SICOT J. 2018;4:30. doi: 10.1051/sicotj/2018007. Epub 2018 Jul 13.
The success of Total Knee Arthroplasty (TKA) hinges on balanced flexion-extension gaps. This paper aims to evaluate the correlation between imbalanced gaps and clinical outcomes, and hence help quantify the imbalanced gap in navigation-assisted total knee arthroplasty.
We studied 195 knees with an average follow-up of two years. Flexion-extension gaps were obtained from computer calculation upon cementation of implants in both flexion (90°) and extension. The gap difference (GD) was defined as the measured difference between the gaps in flexion and extension.
At 2 years after surgery, the mean ROM in the balanced group, with GD less than or equal to 2 mm, was 115.1° ± 16.6° and the mean ROM in the imbalanced group was 116.7° ± 12.1°. This was not statistically significant with p-value 0.589. Balanced flexion-extension gaps also did not show significant difference in terms of mechanical alignment, with 0.29 ± 0.89 in the balanced group at 2 years, and 0.65 ± 1.51 in the imbalanced group with p-value 0.123. Balanced gaps however, were associated with improved outcomes in terms of physical functioning, bodily pain, social functioning, Oxford and Knee scores at 6 months and improved social functioning scores at 2 years.
Computer navigation is a useful tool for assessing the gap balance in TKA. Balanced flexion-extension gaps, with gap differences of less than or equal to 2 mm, is associated with improved clinical outcomes at 6 months.
全膝关节置换术（TKA）的成功取决于屈伸间隙的平衡。本文旨在评估间隙不平衡与临床结果之间的相关性，从而有助于量化导航辅助全膝关节置换术中的间隙不平衡。
我们研究了195个膝关节，平均随访两年。在植入物骨水泥固定后，于屈膝（90°）和伸膝位通过计算机计算获得屈伸间隙。间隙差值（GD）定义为屈膝和伸膝间隙的测量差值。
术后2年，间隙差值小于或等于2毫米的平衡组平均活动范围（ROM）为115.1°±16.6°，不平衡组平均ROM为116.7°±12.1°。p值为0.589，差异无统计学意义。平衡的屈伸间隙在机械对线方面也无显著差异，2年时平衡组为0.29±0.89，不平衡组为0.65±1.51，p值为0.123。然而，平衡的间隙与6个月时身体功能、身体疼痛、社会功能、牛津膝关节评分的改善以及2年时社会功能评分的改善相关。
计算机导航是评估全膝关节置换术中间隙平衡的有用工具。间隙差值小于或等于2毫米的平衡屈伸间隙与6个月时临床结果的改善相关。
