Sabo Marlis T, McDonald Colin P, Ferreira Louis M, Johnson Jim A, King Graham J
Bioengineering Laboratory, The Hand and Upper Limb Center, Lawson Research Institute, St. Joseph's Health Care, University of Western Ontario, London, Ontario, Canada.
J Hand Surg Am. 2011 Jan;36(1):74-80. doi: 10.1016/j.jhsa.2010.09.037.
Osteochondritis dissecans (OCD) of the capitellum most commonly affects adolescent pitchers and gymnasts, who present with pain and mechanical symptoms. Patients with larger lesions have poorer outcomes, possibly related to increased contact pressures on the surrounding articular surface with or without instability. The purpose of this in vitro study was to determine whether displaced OCD lesions of the capitellum lead to altered kinematics and stability of the elbow.
We mounted 9 fresh-frozen cadaveric arms in an upper extremity joint testing system, with cables attaching the tendons of the major muscles to motors and pneumatic actuators. An electromagnetic receiver on the ulna enabled quantification of the kinematics of the radius and ulna with respect to the humerus. We used 3-dimensional computed tomography scans and computer-assisted techniques to navigate sequential osteochondral defects ranging in size from 12.5% to 100% of the capitellum. The arms were subjected to active and passive flexion in both the vertical and valgus positions with the forearm in both pronation and supination.
We found no significant differences in valgus angulation or ulnar rotation between any of the OCD lesions and the intact elbow during flexion, regardless of arm position or forearm rotation.
Osteochondritis dissecans lesions of the capitellum, both small and large, did not alter the ulnohumeral kinematics and stability with intact collateral ligaments. Therefore, excision of unfixable osteochondral fragments of the capitellum in the setting of intact collateral ligaments can be considered without the risk of creating instability.
肱骨小头剥脱性骨软骨炎（OCD）最常影响青少年投手和体操运动员，这些患者会出现疼痛和机械性症状。病损较大的患者预后较差，这可能与周围关节面接触压力增加有关，无论有无不稳定情况。本体外研究的目的是确定肱骨小头移位性OCD病损是否会导致肘关节运动学改变和稳定性下降。
我们将9具新鲜冷冻尸体手臂安装在上肢关节测试系统中，用缆线将主要肌肉的肌腱连接到电机和气动致动器上。尺骨上的电磁接收器能够量化桡骨和尺骨相对于肱骨的运动学情况。我们使用三维计算机断层扫描和计算机辅助技术来定位大小从肱骨小头的12.5%到100%不等的连续性骨软骨缺损。在前臂旋前和旋后时，使手臂在垂直位和外翻位进行主动和被动屈曲。
我们发现，在屈曲过程中，无论手臂位置或前臂旋转情况如何，任何OCD病损与完整肘关节之间的外翻角度或尺骨旋转均无显著差异。
无论大小，肱骨小头剥脱性骨软骨炎病损在侧副韧带完整时不会改变尺肱关节的运动学和稳定性。因此，在侧副韧带完整的情况下，可以考虑切除肱骨小头无法固定的骨软骨碎片，而不会有造成不稳定的风险。
