Gabriel Mary T, Pfaeffle H James, Stabile Kathryne J, Tomaino Matthew M, Fischer Kenneth J
Musculoskeletal Research Center, Department of Orthopaedic Surgery, University of Pittsburgh, Pittsburgh, PA, USA.
J Hand Surg Am. 2004 Mar;29(2):293-8. doi: 10.1016/j.jhsa.2003.10.023.
For severe forearm injuries such as an Essex-Lopresti fracture-dislocation, functional reconstruction necessitates repair of the interosseous ligament (IOL) to restore normal load sharing between the radius and ulna. Locating or tensioning such a reconstruction improperly can lead to abnormal load sharing and/or restriction of forearm rotation. The normal IOL strains should indicate the proper location of reconstruction grafts and the proper forearm rotation for tensioning the grafts. The objective of this study was to quantify the passive strain distribution of the IOL of the forearm with passive rotation of the forearm throughout the range of motion.
The 3-dimensional motions of the radius with respect to the ulna were measured throughout forearm rotation in 10 cadaveric forearms by using an instrumented spatial linkage. From the bone motions and ligament insertion site geometry from dissection and computed tomographic scanning, insertion site motions were determined and used to calculate changes in ligament fiber lengths.
The measured strain distribution in the IOL was nonuniform and varied with forearm rotation. The overall magnitude of IOL strain was found to be greatest in supination and smallest in pronation. In supination the strains varied across fibers with strains being greatest in the distal fibers and lowest in the proximal fibers. Strains in neutral rotation were uniform across fibers. Although fibers were generally slack in pronation proximal fibers were less slack than distal fibers.
The results of this study indicate that fiber strains in the IOL vary from proximal to distal and depend on forearm rotation. Our data suggest that to prevent restriction of forearm rotation all grafts should be tensioned in supination, where measured strains were generally highest. Our data also suggest that a 2-bundle IOL reconstruction may be necessary for proper load transfer between the radius and ulna in both supination and pronation.
对于严重的前臂损伤，如埃塞克斯-洛普雷斯蒂骨折脱位，功能重建需要修复骨间韧带（IOL），以恢复桡骨和尺骨之间的正常负荷分担。重建时IOL定位不当或张力调整不当会导致负荷分担异常和/或前臂旋转受限。正常的IOL应变应能指示重建移植物的正确位置以及用于张紧移植物的前臂正确旋转角度。本研究的目的是在前臂整个运动范围内被动旋转时，量化前臂IOL的被动应变分布。
使用仪器化空间连杆装置，在10具尸体前臂的整个前臂旋转过程中，测量桡骨相对于尺骨的三维运动。根据解剖和计算机断层扫描得到的骨运动和韧带附着点几何形状，确定附着点运动并用于计算韧带纤维长度的变化。
IOL中测得的应变分布不均匀，且随前臂旋转而变化。发现IOL应变的总体大小在旋后时最大，在旋前时最小。在旋后时，各纤维的应变不同，远端纤维的应变最大，近端纤维的应变最小。中立旋转时纤维的应变是均匀的。虽然在旋前时纤维通常松弛，但近端纤维比远端纤维松弛程度小。
本研究结果表明，IOL中的纤维应变从近端到远端各不相同，并取决于前臂旋转。我们的数据表明，为防止前臂旋转受限，所有移植物都应在旋后时张紧，此时测得的应变通常最高。我们的数据还表明，对于在旋后和旋前时桡骨和尺骨之间的正确负荷传递，可能需要进行双束IOL重建。
