Swarup Ishaan, Elattar Osama, Rozbruch S Robert
Limb Lengthening and Complex Reconstruction Service, Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021, USA.
Orthopaedic Sports Medicine, Boston University School of Medicine, 850 Harrison Avenue, Dowling 2 North, Boston, MA 02118, USA.
Knee. 2017 Jun;24(3):608-614. doi: 10.1016/j.knee.2017.02.004. Epub 2017 Mar 18.
Patellar instability can cause significant disability in both pediatric and adult patients, and it is associated with several factors including genu valgum. In this study, we describe the role of a lateral opening wedge distal femoral osteotomy (DFO) combined with lateral retinacular release in addressing genu valgum with associated patellar instability. The rationale for this approach is to medialize the patellar tendon insertion and decrease the Q angle with DFO.
A consecutive series of patients were studied, and our outcomes of interest included improvements in radiographic measures and patient outcomes. Radiographic improvement was assessed using patella congruency angle (PCA), mechanical axis deviation (MAD), and lateral distal femoral angle (LDFA). Patient outcomes were assessed using Oxford Knee scores, KOOS-PS scores, VAS pain scores, and Kujala scores.
We studied eight patients (10 knees) that underwent a lateral opening wedge DFO for genu valgum and patellar instability. Mean follow-up duration was 27 months. PCA improved from 30.4° lateral preoperatively to 5.7° lateral postoperatively (p=0.016). Similarly, MAD improved from 33.1mm lateral to 6.5mm medial, and LDFA improved from 82.4° to 92.7° after surgery (p=0.002). There were significant improvements in VAS pain and Kujala scores after surgery (p<0.05), and a trend towards improvement in KOOS-PS scores (p=0.14). The mean Oxford Knee score at follow-up was 36.25.
There is an important relationship between mechanical alignment and patellar instability. Lateral opening wedge DFO is an effective treatment for patellar instability in patients with genu valgum.
髌骨不稳定可导致儿童和成年患者出现严重残疾，且与多种因素相关，包括膝外翻。在本研究中，我们描述了外侧开口楔形股骨远端截骨术（DFO）联合外侧支持带松解在治疗伴有髌骨不稳定的膝外翻中的作用。这种方法的基本原理是通过DFO使髌腱止点内移并减小Q角。
对一系列连续的患者进行研究，我们感兴趣的结果包括影像学测量指标的改善和患者的预后。使用髌骨适合角（PCA）、机械轴偏移（MAD）和股骨远端外侧角（LDFA）评估影像学改善情况。使用牛津膝关节评分、膝关节骨关节炎疗效评分（KOOS-PS）、视觉模拟评分法（VAS）疼痛评分和库贾拉评分评估患者预后。
我们研究了8例（10膝）因膝外翻和髌骨不稳定接受外侧开口楔形DFO的患者。平均随访时间为27个月。PCA从术前的外侧30.4°改善至术后的外侧5.7°（p = 0.016）。同样，MAD从外侧33.1mm改善至内侧6.5mm，LDFA术后从82.4°改善至92.7°（p = 0.002）。术后VAS疼痛评分和库贾拉评分有显著改善（p < 0.05），KOOS-PS评分有改善趋势（p = 0.14）。随访时牛津膝关节评分的平均值为36.25。
机械对线与髌骨不稳定之间存在重要关系。外侧开口楔形DFO是治疗膝外翻患者髌骨不稳定的有效方法。
