Moya Daniel, Poitevin Luciano A, Postan Daniel, Azulay Guillermo A, Valente Sergio, Giacomelli Fernando, Mamone Luis A
Department of Orthopaedic Surgery, Buenos Aires British Hospital, Buenos Aires, Argentina.
Department of Anatomy, School of Medicine-University of Buenos Aires, Buenos Aires, Argentina.
JSES Open Access. 2018 Sep 22;2(4):183-189. doi: 10.1016/j.jses.2018.07.001. eCollection 2018 Dec.
The medial coracoclavicular ligament (MCCL), is a structure that shows defined morphologic and histologic features. However, little attention has been paid to the MCCL to date. This study was conducted to (1) determine whether the MCCL is a constant structure, (2) analyze its mechanical properties, and (3) determine its possible role in acromioclavicular (AC) stability.
AC joints, lateral coracoclavicular ligaments (LCCLs; conoid and trapezoid), and MCCLs were dissected in 30 fresh frozen upper limbs. In 6 of these specimens, we performed a sequential sectioning following the aforementioned order. A 20-N cephalad force was applied to the lateral clavicle at each step, recording the AC distance and coracoclavicular space and their variation. In 6 other specimens, we evaluated the anteroposterior motion of the clavicle following the MCCL section. Biomechanical testing was performed in 8 specimens, comparing the resistance of the MCCL to the LCCLs.
The MCCL in all of the specimens featured a sharp-edge bundle stretching from the coracoid process to the clavicle and subclavius sheath. It showed ligament-like mechanical properties although less tensile resistance than the LCCLs. Once the AC and LCCLs were sectioned, transection of the MCCL determined a significant increase in both cephalad and posterior displacement.
The MCCL is a constant structure with the mechanical behavior of a ligament. It may act as the last container of the coracoclavicular space both in cephalad and posterior directions, precluding additional displacement in the absence of the LCCLs.
内侧喙锁韧带（MCCL）是一种具有明确形态学和组织学特征的结构。然而，迄今为止，MCCL很少受到关注。本研究旨在：（1）确定MCCL是否为恒定结构；（2）分析其力学性能；（3）确定其在肩锁关节（AC）稳定性中的可能作用。
对30例新鲜冷冻上肢的AC关节、外侧喙锁韧带（LCCL；圆锥韧带和梯形韧带）和MCCL进行解剖。在其中6个标本中，我们按照上述顺序进行连续切片。在每个步骤中，向锁骨外侧施加20N的头向力，记录AC距离和喙锁间隙及其变化。在另外6个标本中，我们评估了切断MCCL后锁骨的前后运动。对8个标本进行生物力学测试，比较MCCL与LCCL的阻力。
所有标本中的MCCL均有一束边缘锐利的韧带，从喙突延伸至锁骨和锁骨下肌鞘。它表现出类似韧带的力学性能，尽管抗张强度低于LCCL。一旦切断AC和LCCL，切断MCCL会导致头向和后向位移均显著增加。
MCCL是一种具有韧带力学行为的恒定结构。它可能在头向和后向方向上作为喙锁间隙的最后一道屏障，在没有LCCL的情况下防止额外的位移。
