Department of Orthopedic Surgery, Washington University School of Medicine/Barnes-Jewish Hospital, 660 S. Euclid Avenue, Campus Box 8233, St. Louis, MO, 63110, USA.
Department of Orthopedic Surgery, Rush University Medical Center, 1611 West Harrison Street, Suite 300, Chicago, IL, 60612, USA.
Knee Surg Sports Traumatol Arthrosc. 2018 May;26(5):1506-1514. doi: 10.1007/s00167-017-4507-9. Epub 2017 Mar 15.
It has been hypothesized that under-correction of a preoperative varus deformity may be more natural and improve outcomes after total knee arthroplasty (TKA). This study's purpose was to assess the impact of hip-knee-ankle (HKA) alignment and joint line obliquity on TKA outcomes for the varus knee.
All patients with a preoperative varus deformity received both preoperative and postoperative standing, full-length radiographs from which two independent observers performed radiographic measurements including the HKA axis and mechanical medial proximal tibial angle (mMPTA). Patients were categorized based on their HKA into neutral (0° ± 3°), mild varus (-6° to -3°), severe varus (≤ -6°), and valgus (>3°) cohorts, and separately categorized based on their mMPTA into neutral (90° ± 2°), mild varus (86°-88°), severe varus (<86°), and valgus (>92°) cohorts.
Two hundred and fifty-six patients (mean age 63.8 ± 9.0 years, BMI 33.0 ± 6.2 kg/m, follow-up 1.3 ± 0.6 years) were included. There was no difference in the postoperative SF-12 physical component, mental component, Oxford knee, Forgotten Joint Score, or incremental improvement in scores based on the postoperative alignment category for either the HKA or mMPTA. There was no correlation between the magnitude of change in HKA (r = 0.03-0.1) and mMPTA (r = 0.02-0.1) from preoperatively to postoperatively with clinical outcomes.
In patients undergoing TKA for a preoperative varus deformity, a specific postoperative HKA or mMPTA alignment category was not associated with improved outcomes. Therefore, categorization of optimal postoperative alignment after TKA may not be possible as static, coronal alignment is just one of many variables that can impact clinical outcomes. Future investigations focusing on the combination of static images with dynamic examinations and ligamentous balancing may shed further insight into the controversy and importance of coronal alignment following TKA.
III.
有假说认为，对于术前内翻畸形，矫枉过正可能更符合自然状态，并改善全膝关节置换术（TKA）后的效果。本研究旨在评估髋膝踝角（HKA）对线和关节线倾斜对内翻膝 TKA 效果的影响。
所有术前存在内翻畸形的患者均接受术前和术后站立位全长位 X 线片检查，由两位独立观察者进行 X 线测量，包括 HKA 轴和机械性内侧胫骨近端角（mMPTA）。根据 HKA 将患者分为中立位（0°±3°）、轻度内翻（-6°至-3°）、重度内翻（≤-6°）和外翻（＞3°）组，根据 mMPTA 分别分为中立位（90°±2°）、轻度内翻（86°-88°）、重度内翻（＜86°）和外翻（＞92°）组。
共纳入 256 例患者（平均年龄 63.8±9.0 岁，BMI 33.0±6.2 kg/m²，随访 1.3±0.6 年）。HKA 和 mMPTA 的术后 SF-12 生理评分、心理评分、牛津膝关节评分、遗忘关节评分以及基于术后对线的评分增量改善方面，术后 HKA 或 mMPTA 分类无差异。HKA（r=0.03-0.1）和 mMPTA（r=0.02-0.1）从术前到术后的变化幅度与临床结果无相关性。
对于行 TKA 治疗的术前内翻畸形患者，特定的术后 HKA 或 mMPTA 对线分类与改善效果无关。因此，TKA 后最佳术后对线的分类可能是不可能的，因为冠状位静态对线只是影响临床效果的众多变量之一。未来的研究集中在静态图像与动态检查和韧带平衡的结合上，可能会进一步深入了解 TKA 后冠状对线的争议和重要性。
III 级。
