Department of Orthopaedic Surgery, University Hospital of Saint Étienne, Saint Étienne, France.
EA 7424-Interuniversity Laboratory of Human Movement Science, University Lyon-University Jean Monnet, Saint Étienne, France.
Am J Sports Med. 2019 May;47(6):1338-1345. doi: 10.1177/0363546519831294. Epub 2019 Apr 3.
Isolated medial patellofemoral ligament reconstruction (iMPFLR) is increasingly used for the surgical treatment of recurrent patellofemoral instability.
The purpose of this study was to identify the clinical and radiological predictors that can significantly influence the functional outcomes after an iMPFLR.
Case series; Level of evidence, 4.
A total of 107 patients (112 ligament reconstructions) who underwent iMPFLR were evaluated with a mean ± SD follow-up of 59 ± 33 months (range, 12-123 months). Functional International Knee Documentation Committee (IKDC) and Kujala scores were assessed preoperatively and every 12 months. Radiological assessment of patellar height and tilt (Laurin angle, Merchant angle, Maldague classification) and computed tomography (CT) scan measurement of patellar tilt (contracted and relaxed quadriceps) and tibial tubercle-trochlear groove distance were performed preoperatively and at 6 months. Femoral tunnel position was assessed following the criteria formulated by Schöttle. The amount of femoral tunnel widening was measured by means of 3-dimensional CT scan at 6 months. Predictors were determined from univariate and multivariate regression analyses integrating clinical and radiological criteria pre- and postoperatively. The dependent variable was defined as the difference between pre- and postoperative scores.
Between pre- and postoperative measurement at last follow-up, a significant improvement for IKDC and Kujala functional scores was observed (Kujala: 57 ± 11.3 to 87 ± 12.9, P < .001; IKDC: 47.8 ± 13.1 to 79 ± 15.8, P < .001). Demographics (age, body mass index, sex), dislocation characteristics (number of dislocations, time between first dislocation and surgery, age at first dislocation, mechanism of first dislocation, knee side), clinical data (frontal limb alignment, hyperlaxity, recurvatum, pre- and postoperative range of motion), and complications (quadriceps atrophy, complex regional pain syndrome) did not influence functional scores. The predictors of lower improvement in functional scores included small correction of the patellar tilt reported on the CT scan measurement, malpositioning of the femoral tunnel, and a widening of this tunnel near the medial cortex. Malpositioning of the femoral tunnel was correlated with tunnel widening, and patients with anterior and proximal malpositioning experienced stiffness in flexion.
Overall, iMPFLR demonstrated good outcomes. Predictors influencing the functional results were identified. Less improvement in clinical outcome was reported for patients with a high preoperative patellar tilt and only a small correction in tilt and for those who had femoral tunnel malpositioning, which was correlated with tunnel widening.
孤立性内侧髌股韧带重建（iMPFLR）越来越多地用于复发性髌股不稳定的手术治疗。
本研究旨在确定能够显著影响 iMPFLR 后功能结果的临床和影像学预测因素。
病例系列；证据水平，4 级。
对 107 例（112 条韧带重建）接受 iMPFLR 的患者进行评估，平均随访时间为 59 ± 33 个月（范围 12-123 个月）。术前和每 12 个月评估功能国际膝关节文献委员会（IKDC）和 Kujala 评分。术前和术后 6 个月行髌股高度和倾斜（Laurin 角、Merchant 角、Maldague 分类）和 CT 扫描测量髌股倾斜（收缩和放松股四头肌）及髌腱-滑车沟距离。根据 Schöttle 制定的标准评估股骨隧道位置。术后 6 个月通过三维 CT 扫描测量股骨隧道增宽程度。通过术前和术后的单变量和多变量回归分析确定预测因素，将临床和影像学标准整合在一起。因变量定义为术前和术后评分的差值。
末次随访时，IKDC 和 Kujala 功能评分与术前相比有显著改善（Kujala：57 ± 11.3 至 87 ± 12.9，P <.001；IKDC：47.8 ± 13.1 至 79 ± 15.8，P <.001）。人口统计学因素（年龄、体重指数、性别）、脱位特征（脱位次数、首次脱位与手术时间间隔、首次脱位年龄、首次脱位机制、膝关节侧别）、临床数据（额状面肢体对线、过度松弛、后倾、术前和术后活动范围）和并发症（股四头肌萎缩、复杂性局部疼痛综合征）均未影响功能评分。影响功能评分改善较小的预测因素包括 CT 扫描测量时髌股倾斜的小校正、股骨隧道的位置不当以及内侧皮质附近隧道的增宽。股骨隧道位置不当与隧道增宽相关，前位和近端位置不当的患者在弯曲时会出现僵硬。
总体而言，iMPFLR 显示出良好的结果。确定了影响功能结果的预测因素。对于术前髌股倾斜度较高且倾斜度仅得到较小矫正的患者，以及股骨隧道位置不当且与隧道增宽相关的患者，临床结果的改善较小。
