Holmes Connor James, Abelleyra Lastoria Diego Agustín, Roberts Tobias, Ejindu Vivian, Robertson Claire, Hing Caroline
School of Health and Medical Sciences, City St George's University of London, London, UK.
St George's University Hospitals NHS Foundation Trust, London, UK.
Arch Orthop Trauma Surg. 2025 Sep 16;145(1):448. doi: 10.1007/s00402-025-06059-5.
This study investigated the relationship between the vastus medialis obliquus (VMO) cross-sectional area (CSA) and patellofemoral instability (PFI) in both primary and recurrent lateral patellar dislocations (LPD). Our secondary objective was to examine associations between VMO CSA and trochlear dysplasia, tibial tuberosity position, and patellar height in patients with PFI.
Magnetic resonance imaging (MRI) radiographs were retrospectively analysed for 90 patients with primary acute LPD, 90 patients with recurrent LPD, and 56 patients without LPD (control). Measurements of the CSA ratio of the VMO to the whole thigh in three transverse slices were performed to calculate a mean ratio per patient. Additionally, tibial tubercle-trochlear groove (TT-TG) distance, patellar tilt angle (PTA), trochlear sulcus angle (TSA), and Insall-Salvati ratio (ISR) were measured as part of the Dejour Protocol.
The median CSA ratios in primary (0.04, standard deviation [SD]: 0.02) and recurrent (0.04, SD: 0.02) LPD patients were significantly lower than those in the control group (0.07, SD: 0.02) (P < 0.05). Compared with the primary LPD group, the recurrent LPD group presented significantly greater TT-TG distances (16.0, SD: 4.77 mm vs. 13.0, SD: 4.73 mm; p = 0.0101) and PTA (25, SD: 9.79 degrees vs. 19, SD: 15.76 degrees; p = 0.0071). There was no statistically significant correlation between any parameters of the Dejour Protocol and the VMO CSA ratio in patients with primary or recurrent dislocations (P > 0.05).
Patients with both primary and recurrent LPD demonstrated smaller VMO bulk relative to the rest of the thigh compared with controls. These findings indicate an association between reduced VMO size and patellar dislocation; however, causality cannot be inferred from this cross-sectional analysis.
IV.
本研究调查了初次和复发性外侧髌骨脱位（LPD）患者股内侧斜肌（VMO）横截面积（CSA）与髌股关节不稳（PFI）之间的关系。我们的次要目标是研究PFI患者中VMO CSA与滑车发育不良、胫骨结节位置和髌骨高度之间的关联。
对90例初次急性LPD患者、90例复发性LPD患者和56例无LPD患者（对照组）的磁共振成像（MRI）X线片进行回顾性分析。在三个横断面上测量VMO与整个大腿的CSA比值，计算每位患者的平均比值。此外，作为Dejour方案的一部分，测量胫骨结节-滑车沟（TT-TG）距离、髌骨倾斜角（PTA）、滑车沟角（TSA）和Insall-Salvati比值（ISR）。
初次LPD患者（0.04，标准差[SD]：0.02）和复发性LPD患者（0.04，SD：0.02）的CSA比值中位数显著低于对照组（0.07，SD：0.02）（P<0.05）。与初次LPD组相比，复发性LPD组的TT-TG距离显著更大（16.0，SD：4.77mm对13.0，SD：4.73mm；p = 0.0101），PTA也显著更大（25，SD：9.79度对19，SD：15.76度；p = 0.0071）。在初次或复发性脱位患者中，Dejour方案的任何参数与VMO CSA比值之间均无统计学显著相关性（P>0.05）。
与对照组相比，初次和复发性LPD患者的VMO相对于大腿其他部位体积较小。这些发现表明VMO尺寸减小与髌骨脱位之间存在关联；然而，不能从该横断面分析中推断因果关系。
IV级。
