拇指腕掌关节韧带的解剖力学分析及临床意义

目的研究拇指腕掌关节背桡韧带及前斜韧带的解剖学及生物力学特点,测量其弹性模量及延伸率,为伤病时韧带修复提供参考。方法解剖成人男性尸体40例新鲜手标本,制做成大多角骨-韧带-第1掌骨标本,20例保留背桡韧带,20例保留前斜韧带,在生物力学机上测试,测量和计算背桡韧带及前斜韧带的长、宽、厚、最大载荷、弹性模量、延伸率。结果背桡韧带、前斜韧带的最大载荷分别为(213.5±72.4)、(168.7±35.2)N,弹性模量分别为(17.2±6.7)、(9.3±2.5)MPa,延伸率分别为(116.2±21.3)%、(92.7±22.4)%。背桡韧带的最大载荷、弹性模量及延伸率均大于前斜韧带。结论拇指腕掌关节囊内韧带中,背桡韧带刚度较大,韧性较强,对维持关节稳定性起重要作用。前斜韧带刚度较小,韧性较差,韧带退变时容易损伤。拇指腕掌关节炎应该首选重建前斜韧带,且应选用弹性模量及延伸率接近背桡韧带的材料为佳。

Analysis on anatomy and biomechanics of ligaments in carpometacarpal joints of the thumb and clinical significance

Objective To study the anatomic and biomechanical characteristics of the dorsal radial ligament and anterior oblique ligament in carpometacarpal (CPC) joints of the thumb, so as to provide references for ligament repair. Methods Forty fresh hand specimens of adult male cadavers were dissected to make specimen of trapezium bone- ligament-the first metacarpal bone, of which 20 cases retained the dorsal radial ligament and 20 cases retained the anterior oblique ligament, respectively. The ligaments were tested on the biomechanical testing machine, and their length, width, thickness, the maximum load, elastic modulus and elongation rate were measured and calculated. Results For the dorsal radial ligament and anterior oblique ligament, their maximum load was (213.5±72.4) and (168.7±35.2) N, their elastic modulus was (17.2±6.7) and (9.3±2.5) N/mm2, their elongation rate was (116.2±21.3)% and (92.7±22.4)%, respectively. The maximum load, elastic modulus and elongation of the dorsal radial ligament were larger than that of the anterior oblique ligament. Conclusions In the capsular ligament in CPC joints of the thumb, the dorsal radial ligament has a higher stiffness and stronger toughness, which plays an important role in maintaining the stability of the joint. The stiffness of the anterior oblique ligament is smaller, the toughness is poor, which is easy to be damaged. The anterior oblique ligament is suggested to be reconstructed firstly to treat arthritis of CMC joints, and material whose elastic modulus and elongation rate is similar with the dorsal radial ligament should be selected.