合并肘关节脱位的成人后孟氏骨折的形态特征及治疗

Morphology and surgical treatment of posterior Monteggia fracture with associated ulnohumeral dislocation

目的探讨合并肘关节脱位的成人后孟氏骨折的形态特征、损伤机制和治疗方法。方法回顾性分析自2011年1月至2013年12月收治的11例伴肘关节脱位的成人后孟氏骨折患者资料，男8例，女3例，年龄21-59岁，平均（43．3±11．6）岁。10例为高能量损伤，另外1例为摔倒后骨折；Jupiter分型ⅡA型9例，ⅡB型1例，Ⅱc型I例。分析其一般资料、形态特征和治疗方法，并随访术后肘关节功能。结果伴肘关节脱位的成人后孟氏骨折具有以下特征：①尺骨骨折位于鹰嘴冠状突平面的损伤，冠状突均存在尖端和前内侧两个骨块，部分可合并有外侧骨块；②冠状突尖端骨块较小；③上尺桡关系常正常；④外侧副韧带损伤和桡骨头骨折发生率较高。典型ⅡA型骨折的复位及固定顺序：牵开尺骨鹰嘴即可暴露冠状突骨块及桡骨头骨折，首先固定冠状突尖端骨块，然后复位冠状突前内侧（及前外侧）骨块和桡骨头骨折块，继而复位尺骨鹰嘴，尺骨鹰嘴复位固定后一般桡骨头可复位，然后修复外侧副韧带。尺骨鹰嘴采用解剖钢板固定，前内侧骨块往往需要单独一块掌骨“T”型钢板固定。10例获得随访，平均随访22．7个月。伸屈活动度为45°-140°，平均104°；旋转活动度为60°-180°，平均128°。根据BrobergMorrey评分，2例为优，5例为良，2例为可，1例为差，优良率70％。结论合并肘关节脱位的成人后孟氏骨折上尺桡关节大多正常，冠状突常粉碎且尖端骨块较小，外侧结构损伤发生率高，提示此类骨折与后孟氏骨折可能具有不同的损伤机制，其治疗除复位和固定尺骨外，更重要的是恢复肘关节的稳定性。

Objective To investigate the morphological properties of posterior Monteggia lesion with associated elbow dislocation, to propose its injury mechanism, and to present its surgical methods and its outcomes. Methods The injury mecha- nism, radiographs and surgical records of patients with posterior Monteggia fractures and associated elbow dislocation were retro- spectively reviewed from January 2011 to December 2013. 11 patients were included, with 43.3 years old on average. 10 were re- sulted from high-energy injuries. According to the Jupiter classification, II A fracture-dislocation 9 eases, II B fracture-dislocation 1 case and II C fracture-dislocation 1 case. The general medical data, morphological properties, and the surgical methods. Func- tional outcomes were followed up. Results These cases had several intrinsic morphologic features： fractures of the coronoid tip and its anteromedial aspect; dislocation of the oleeranon from the trochlear notch; fracture of the radial head and disruption of the lateral collateral ligament; a normal proximal radioulnar joint. Operation was carried out with emphasis on elbow stability restora- tion. All patients underwent the primary operations in the supine position and a routine posterior approach was used. An additional anterior approach was used in 1 case （ II B）. The coronoid tip was first fixed, followed by the anteromedial coronoid fragment, the radial head, the oleeranon, and then the LCL. An anatomic olecranon plate was used as the fundamental fixation device. Anterome- dial coronoid fractures were mostly fixed with a T-shaped metacarpal plate. The eoronoid tip fractures were fixed with screw, K- wire or suture, and the injured LCL was repaired with suture anchors. Ten of the 11 patients were followed up with a mean period of 22.7 months. The extension-flexion motion ranged from 45°- 140° （104° average）, and the pronation-supination motion ranged from 45° - 180° （128° average）. According to the Broberg and Morrey functional index, the excellent to good ratio was 70%. Conclusion Patients with posterior Monteggia fracture and associated ulnohumeral dislocation have small and comminuted coronoid fractures, and mostly have a normal PRUJ relationship. It might experience a different mechanism to those of the posterior Monteg- gia fracture without elbow dislocation. Emphases should be address to restore the rotation stability of the elbow when operation.