喙肩弓对肩关节前上方稳定性作用的生物力学研究

A biomechanical study on anterosuperior stability of coracoacromial arch in shoulder joint

目的探讨对喙肩弓进行不同程度破坏时肩关节前上方稳定性所受到的影响。方法选取新鲜成人冷冻肩关节尸体标本36个,随机平均分为3组后进行不同的处理。组1,保留完整的喙肩韧带;组2,破坏一半喙肩韧带;组3,将喙肩韧带全部破坏。然后分别将肩关节标本固定生物力学试验机上进行力学实验;对肱骨干施加轴向压力时,肱骨头向前上方移动,记录肱骨头在50 N压力时的位移距离。结果在50 N压力作用下,组1、2、3肱骨头位移距离分别为(2.50±0.59)、(5.38±0.71)、(6.49±0.81)mm。3组数据组间比较均存在明显统计学差异(P<0.05)。结论喙肩弓的破坏会影响肩关节前上方的稳定性。喙肩弓的破坏程度越大,肩关节前上方的稳定性就越差。

Objective To study the effects on anterosuperior stability of the shoulder joint when the coracoacromial arch is damaged at different degrees.Methods Thirty-six specimens of the fresh frozen adult shoulder joints were randomly and evenly divided into 3 groups.Group 1,reserving integrity of the coracoacromial ligament of the shoulder joint;Group 2,dissecting half of the coracoacromial ligament attachment sector on the acromion;Group 3,grinding all the coracoacromial ligament attachment sector on the acromion.The specimens of the shoulder joint were fixed on test bench of the biomechanical testing machine.The axial pressure was applied on the humeral shaft,and the humeral head was pushed to move in anterosuperior direction.The displacement distance of the humeral head under 50 N pressure was then recorded.Results Under 50 N pressure,the displacement distance of the humeral head in Group 1,2,3 was（2.50 ± 0.59）,（5.38 ± 0.71）,（6.49 ± 0.81） mm,respectively,which showed significantly statistic differences among 3 groups（P〈0.05）.Conclusions The damage to the coracoacromial arch will affect the anterosuperior stability of the shoulder joint.The greater damage to the coracoacromial arch will lead to the lower anterosuperior stability of the shoulder joint.