Chow Roxanne M, Guzman Maurice S, Dao Quang
Department of Orthopedic Surgery, The Children's Hospital at Westmead, Westmead, NSW, Australia.
J Pediatr Orthop. 2016 Sep;36(6):640-4. doi: 10.1097/BPO.0000000000000511.
Juvenile osteochondritis dissecans (OCD) of the medial femoral condyle (MFC) is one of the most common causes of knee pain in adolescents. Wilson sign reproduces knee pain with internal rotation of the tibia during extension of the knee from 90 to 30 degrees due to impingement of the tibial eminence on the MFC. This impingement may result in microtrauma and contribute to lesion formation. The purpose of this study was to evaluate anatomic factors that may increase the likelihood of impingement by using magnetic resonance imaging scans of patients with MFC OCD lesions to measure tibial eminence height and femoral notch width.
A retrospective, case-control study was performed using the radiology database at our institution between July 2009 and February 2014. Magnetic resonance imagings of patients with MFC OCD lesions and matched controls were identified. For each patient, tibial eminence height and femoral notch width were measured and then normalized for patient size [creating the tibial eminence height normalized, and the notch width index (NWI), respectively]. Values for OCD and control knees were compared using Student t test. Interrater and intrarater reliability were calculated using intraclass correlation coefficients.
Thirty-five MFC OCD patients and matched controls were identified. Comparison of the groups showed a significantly smaller NWI in MFC OCD knees than in the matched controls (0.2620±0.0248 vs. 0.2886 ±0.0323, P=0.0003). There was no difference in tibial eminence height normalized between groups (0.1387±0.0161 vs. 0.1428±0.0108, P=0.21). Interrater and intrarater reliability of all measurements was good to excellent (0.81 to 1.00) when measurements were made using bony margins.
Knees with MFC OCD lesions have significantly smaller NWIs than matched controls. This anatomic factor may increase the likelihood of tibial eminence impingement and contribute to OCD lesion formation.
Level III-case-control study.
股骨内侧髁（MFC）的青少年剥脱性骨软骨炎（OCD）是青少年膝关节疼痛最常见的原因之一。威尔逊征是指在膝关节从90度伸展到30度的过程中，由于胫骨隆起撞击MFC，导致胫骨内旋时膝关节疼痛。这种撞击可能会导致微创伤，并促使病变形成。本研究的目的是通过对患有MFC OCD病变的患者进行磁共振成像扫描，测量胫骨隆起高度和股骨切迹宽度，以评估可能增加撞击可能性的解剖学因素。
2009年7月至2014年2月期间，利用我们机构的放射学数据库进行了一项回顾性病例对照研究。确定了患有MFC OCD病变的患者和匹配对照的磁共振成像。对每位患者测量胫骨隆起高度和股骨切迹宽度，然后根据患者体型进行标准化（分别得出标准化的胫骨隆起高度和切迹宽度指数（NWI））。使用学生t检验比较OCD组和对照组膝关节的值。使用组内相关系数计算评估者间和评估者内的可靠性。
确定了35例MFC OCD患者和匹配对照。两组比较显示，MFC OCD膝关节的NWI明显小于匹配对照（0.2620±0.0248对0.2886±0.0323，P = 0.0003）。两组间标准化的胫骨隆起高度没有差异（0.1387±0.0161对0.1428±0.0108，P = 0.21）。当使用骨边缘进行测量时，所有测量的评估者间和评估者内可靠性均良好至优秀（0.81至1.00）。
患有MFC OCD病变的膝关节的NWI明显小于匹配对照。这一解剖学因素可能会增加胫骨隆起撞击的可能性，并促使OCD病变形成。
III级病例对照研究。
