Department of Orthopaedics, Cagayan Valley Medical Center, Tuguegarao City, Cagayan, Philippines.
Clin Orthop Relat Res. 2013 May;471(5):1472-83. doi: 10.1007/s11999-012-2618-7.
Coronal alignment is considered key to the function and longevity of a TKA. However, most studies do not consider femoral and tibial anatomical features such as lateral femoral bowing and the effects of these features and subsequent alignment on function after TKA are unclear.
QUESTIONS/PURPOSES: We therefore determined (1) the prevalence of lateral femoral bowing, varus femoral condylar orientation, and severe tibia plateau inclination in female Koreans undergoing TKA; (2) whether postoperative alignments are affected by these anatomical features and improved by the use of navigation; and (3) whether postoperative coronal alignments are associated with function.
We measured alignment in 367 knees that underwent TKA and 60 sex- and age-matched normal knees (control group). We determined patterns and degrees of femoral bowing angle, femoral condylar orientation, and tibial plateau inclination on preoperative full-limb radiographs. Postoperatively, coronal alignment of limbs and of femoral and tibial components was measured. We compared American Knee Society scores, WOMAC scores, and SF-36 scores in aligned knees and outliers (beyond ± 3° or ± 2°) at 1 year.
The prevalence of lateral femoral bowing was 88% in the TKA group and 77% in the control group. Mean femoral condylar orientation angle was varus 2.6° in the TKA group and valgus 1.1° in the control group, and mean tibial plateau inclination was varus 8.3° in the TKA group and varus 5.4° in the control group. Femoral lateral bowing and varus femoral condylar orientation were associated with postoperative alignments. Several clinical outcome scales were inferior in the outliers in mechanical tibiofemoral angle, anatomical tibiofemoral angle, and tibial coronal alignment but not in femoral coronal alignment outliers.
Lateral femoral bowing, varus condylar orientation, and severe varus inclination of the tibia plateau should be considered when performing TKA in Korean patients or patients with otherwise similar anatomical features.
冠状面对线被认为是 TKA 功能和长期效果的关键。然而，大多数研究并未考虑股骨和胫骨的解剖特征，例如股骨外侧弯曲以及这些特征及其对 TKA 后功能的影响尚不清楚。
问题/目的：因此，我们确定了（1）接受 TKA 的韩国女性中股骨外侧弯曲、股骨髁间矢状面倾斜和胫骨平台严重倾斜的流行率；（2）这些解剖特征是否会影响术后对线，并通过导航来改善；以及（3）术后冠状面对线是否与功能相关。
我们测量了 367 例接受 TKA 和 60 例性别和年龄匹配的正常膝关节（对照组）的膝关节对线。我们在术前全长 X 线片上确定了股骨弯曲角度、股骨髁间矢状面倾斜和胫骨平台倾斜的模式和程度。术后测量下肢、股骨和胫骨组件的冠状面对线。我们比较了对线良好的膝关节和 1 年时的对线不良膝关节（超出±3°或±2°）的美国膝关节协会评分、WOMAC 评分和 SF-36 评分。
TKA 组的股骨外侧弯曲发生率为 88%，对照组为 77%。TKA 组股骨髁间矢状面倾斜平均为 2.6°，对照组为 1.1°，TKA 组胫骨平台倾斜平均为 8.3°，对照组为 5.4°。股骨外侧弯曲和股骨髁间矢状面倾斜与术后对线有关。在机械性胫股角、解剖性胫股角和胫骨冠状对线的对线不良患者中，几个临床结果量表的评分较低，但在股骨冠状对线不良患者中则不然。
在韩国患者或具有类似解剖特征的患者中进行 TKA 时，应考虑股骨外侧弯曲、股骨髁间矢状面倾斜和胫骨平台严重倾斜。
