移植物重建前臂骨间膜的生物力学研究

A biomechanical study of the reconstruction of the forearm interosseous membrane with the graft substitute

目的 探讨3种移植物与正常前臂骨间膜比较限制桡骨向近端移位的能力.方法 12具新鲜冷冻尸体前臂标本制成生物力学模型,腕、肘关节中立位固定于生物材料实验机上加载恒定100 N的轴向负荷,测量桡骨相对于肱骨小头向近端移位的距离.首先测试桡骨头切除骨间膜完整的标本,然后切断骨间膜,分别利用掌长肌腱、桡侧腕屈肌腱、同种异体跟腱重建每具标本的骨间膜中央束.每种测试状态重复加载10次,第1次至第10次桡骨向近端位移的增加代表移植物被拉伸的长度.结果 桡骨向近端的平均位移分别为（3.02±3.56） mm（完整骨间膜）、（6.78 ±4.12） mm（掌长肌腱）、（5.08 ±6.78） mm（桡侧腕屈肌腱）、（4.13 ±4.73） mm（同种异体跟腱）,两两比较差异有统计学意义（P＜0.05）.移植物被拉伸的平均长度分别为（0.31 ±2.12） mm（完整骨间膜）、（1.82±3.26） mm（掌长肌腱）、（1.72±4.37） mm（桡侧腕屈肌腱）、（0.36 ±2.89） mm（同种异体跟腱）,其中掌长肌腱与桡侧腕屈肌腱,同种异体跟腱与完整骨间膜比较差异无统计学意义（P＞0.05）,其余两两比较差异有统计学意义（P＜0.05）.结论 没有一种移植物重建可以像正常骨间膜一样有效地限制桡骨向近端移位.如果考虑通过骨间膜重建来治疗前臂Essex-Lopresti损伤,3种移植物中同种异体跟腱是较为理想的选择.

Objective To study the abilities of 3 graft tissues to linit proximal radial displacement compared with the native interosseous membrane （IOM） of the forearm.Methods Twelve biomechanics models harvested from fresh-frozen cadaveric forearms were mounted on testing machine.The specimens were tested under 100 newtons of constant axial load with the elbow and wrist in neutral rotation.Proximal displacement of the radius relative to the capitellum was measured.With the radial head excised specimens were first tested with the IOM intact.The IOM was then sectioned and central band IOM reconstruction were performed on each specimen using the following tissues：palmaris longus tendon,flexor carpi radialis （FCR） tendon,and achilles tendon allograft.Ten loading cycles were performed with each test configuration.The increase in proximal displacement between the first and 10th loading cycles represented the elongation of the graft.Results Mean proximal radial displacements were （3.02 ± 3.56） mm （intact IOM）,（6.78 ± 4.12） mm （palmaris longus tendon）,（5.08 ± 6.78） mm （FCR tendon）,（4.13 ± 4.73） mm （achilles tendon allograft）,all means were significantly different from each other.Mean graft elongations were （0.31 ± 2.12） mm （intact IOM）,（1.82 ± 3.26） mm （palmaris longus tendon）,（1.72 ± 4.37） mm （FCR tendon）,（0.36±2.89） mm （achilles tendon allograft）.All means were significantly different from each other with the exception of means for palmaris longus tendon vs.FCR tendon and achilles tendon allograft vs.intact IOM.Conclusion No graft reconstruction limited proximal radial displacement as effectively as the native IOM.Of the 3 graft tissues the achilles tendon allograft is the best choice if IOM reconstruction is considered for treatment of an Essex-Lopresti injury.