Lippert William C, Owens Richard F, Wall Eric J
Cincinnati Children's Hospital Medical Center, Division of Orthopaedics, Cincinnati, OH 45229, USA.
J Pediatr Orthop. 2010 Sep;30(6):598-605. doi: 10.1097/BPO.0b013e3181e4f55b.
Salter-Harris (SH) III fractures of the distal femur, although rare, can have devastating effects. The purposes of this study were to: (1) compare the intra-articular fracture displacement measured on plain x-ray and magnetic resonance imaging (MRI) or computed tomography (CT) scan and (2) report the outcomes of patients with a SH III fracture of the distal femur.
All SH III distal femur fractures treated at a large Children's Hospital with a Level I Pediatric Trauma Center between 1995 and 2006 were retrospectively reviewed. A total of 14 patients (average age: 13 y, 11 mo; range: 7 y, 8 mo to 17 y, 11 mo) with an average follow-up time of 21.50 months (range: 2 to 47 mo) were included in this study. Fracture displacement on plain x-ray was compared with the fracture displacement measured on MRI or CT scan. The average time between the initial plain x-ray and MRI or CT scan was 37.48 days (range: 3 h to 6 mo).
Plain x-rays significantly underestimated the displacement of SH III fractures versus MRI or CT scan. Six patients who had both plain x-ray and MRI or CT scan had a measured displacement of 0.42 mm and 2.70 mm, respectively (paired Student t test, P=0.005). Ten of the 14 patients (71%) had no physical limitations and full knee motion at their most recent follow-up visit. The treatment of 4 patients (29%) was changed based on the findings of the additional MRI or CT scan.
This study and earlier studies have shown a high rate of poor results with SH III fractures of the distal femur. This type of fracture pattern is extremely unstable and the true displacement is often underestimated by x-rays. Thus, it is strongly recommended that an MRI or CT scan be obtained on every SH III fracture of the distal femur. Moreover, any SH III fracture visible on plain radiographs should be treated with open reduction, internal fixation.
Level IV.
股骨远端的Salter-Harris（SH）III型骨折虽罕见，但可能产生严重后果。本研究的目的是：（1）比较在普通X线片、磁共振成像（MRI）或计算机断层扫描（CT）上测量的关节内骨折移位情况；（2）报告股骨远端SH III型骨折患者的治疗结果。
回顾性分析1995年至2006年期间在一家设有I级儿科创伤中心的大型儿童医院接受治疗的所有股骨远端SH III型骨折病例。本研究共纳入14例患者（平均年龄：13岁11个月；范围：7岁8个月至17岁11个月），平均随访时间为21.50个月（范围：2至47个月）。将普通X线片上的骨折移位与MRI或CT扫描测量的骨折移位进行比较。初次普通X线片与MRI或CT扫描之间的平均时间为37.48天（范围：3小时至6个月）。
与MRI或CT扫描相比，普通X线片显著低估了SH III型骨折的移位情况。6例同时进行了普通X线片和MRI或CT扫描的患者，测量的移位分别为0.42毫米和2.70毫米（配对学生t检验，P = 0.005）。14例患者中有10例（71%）在最近一次随访时无身体限制且膝关节活动完全正常。4例患者（29%）的治疗方案根据额外的MRI或CT扫描结果进行了调整。
本研究及早期研究表明，股骨远端SH III型骨折的不良结果发生率较高。这种骨折类型极其不稳定，X线片常常低估其真实移位情况。因此，强烈建议对每例股骨远端SH III型骨折均进行MRI或CT扫描。此外，普通X线片上可见的任何SH III型骨折均应采用切开复位内固定治疗。
IV级。
