Groupement Hospitalier Nord, Hospices civils de Lyon, Université Claude-Bernard Lyon 1, 103 Grande Rue de la Croix-Rousse, 69004, Lyon, France.
Groupement Hospitalier Nord, Hospices civils de Lyon, Université Lyon, 103 bvd de la Croix Rousse, 69004, Lyon, France.
Knee Surg Sports Traumatol Arthrosc. 2019 Mar;27(3):731-739. doi: 10.1007/s00167-018-5023-2. Epub 2018 Jul 11.
Surgeons mainly consider the anterior anatomy of the distal femur in the treatment of patellar instability (PI) with trochlear dysplasia (TD). Through this research, the idea was to analyse the posterior femoral condyle length in TD. The research team posited the presence of morphological differences in the posterior part of the femoral epiphysis in TD compared to a control group. They also postulated that the posterior bicondylar angle (PCA), in the axial plane, was increased in TD.
This is a single-centre morphological study of 100 patients who had a computed tomography (CT) using the same protocol. 50 patients with PI (25 dysplasias A and 25 B-C-D according to the Dejour classification), and 50 controls were included. All patients presenting a clinical PI were considered for the study. None of these patients had undergone a surgical treatment prior to imaging. Demographic characteristics, BMI, and laterality were comparable in all patients. 20 pilot CT scans were used to establish the methodology. The following measurements were performed: anterior bicondylar angle, PCA, and condylar lengths with respect to the surgical transepicondylar axis. Ratios were calculated in relation to the femoral width. TD was classified according to the Dejour classification in grade A or grades B-C-D. An analysis of variance and a linear model were performed within some groups to investigate which parameters correlated with the classification's grade.
This study showed a link between TD and the PCA: control group (1.4 ± 0.2°), type A group (1.6 ± 0.3°), and types B, C, D group (2.6 ± 0.3°) (p = 0.01). The difference between the control group and types B, C, D TD group was significant (p = 0.002). In groups B, C, D, the PCA was more important, which proves that in these groups the posterior part of the lateral condyle was relatively shorter compared to the medial condyle. The greater the dysplasia, the longer the medial condyle was in the anterior posterior (p = 0.02).
This study shows not only an anterior but also a posterior anomaly in PI with TD. There is a correlation between the severity of the anterior deformation and the PCA: in other words, the knee is placed in valgus in flexure which promotes the external dislocation of the patella. This anatomical study could open a field of research on the development of surgical treatments based on the correction of posterior condylar femoral anomalies in PI.
III.
在治疗伴滑车发育不良（TD）的髌骨不稳定（PI）时，外科医生主要考虑股骨远端的前解剖结构。通过这项研究，研究小组分析了 TD 中股骨后髁长度的形态差异。研究小组假设与对照组相比，TD 患者的股骨骨骺后部存在形态学差异。他们还假设，在轴位上，后双髁角（PCA）增加。
这是一项单中心形态学研究，共纳入了 100 名患者，这些患者均采用相同的方案进行了计算机断层扫描（CT）检查。其中 50 名 PI 患者（25 名 A 型，25 名 B-C-D 型根据 Dejour 分类），50 名对照组患者。所有有临床 PI 的患者均被考虑进行该研究。这些患者在影像学检查前均未接受过手术治疗。所有患者的人口统计学特征、BMI 和侧别在所有患者中均相似。进行了 20 次 CT 扫描以建立方法。进行了以下测量：双髁前角、PCA 以及相对于手术髁间轴的髁长度。计算了与股骨宽度的比值。根据 Dejour 分类将 TD 分为 A 级或 B-C-D 级。在某些组内进行方差分析和线性模型，以研究哪些参数与分类等级相关。
本研究表明 TD 与 PCA 之间存在关联：对照组（1.4±0.2°）、A型组（1.6±0.3°）和 B、C、D 型组（2.6±0.3°）（p=0.01）。对照组与 B、C、D 型 TD 组之间的差异具有统计学意义（p=0.002）。在 B、C、D 组中，PCA 更重要，这证明在这些组中，外侧髁的后部分相对于内侧髁更短。发育不良程度越大，内侧髁在前后方向上越长（p=0.02）。
本研究不仅显示了 PI 伴 TD 的前异常，还显示了后异常。前变形的严重程度与 PCA 之间存在相关性：换句话说，膝关节在弯曲时处于外翻位，这促进了髌骨的外侧脱位。这项解剖学研究可能为基于 PI 中股骨后髁异常的矫正的手术治疗的发展开辟了一个研究领域。
III 级。
