Trapezoid ligament

Trapezoid Ligament

The trapezoid ligament is one of the two components of the coracoclavicular ligament, the other being the conoid ligament. These ligaments are part of the shoulder complex and play a crucial role in stabilizing the acromioclavicular joint.

Anatomy

The trapezoid ligament is a strong, flat, quadrilateral band that is located on the lateral side of the coracoclavicular ligament. It extends from the superior surface of the coracoid process of the scapula to the inferior surface of the clavicle.

Attachments

The trapezoid ligament attaches to the trapezoid line on the inferior surface of the clavicle. It is positioned anteriorly to the conoid ligament, which attaches to the conoid tubercle of the clavicle.

Function

The primary function of the trapezoid ligament is to prevent excessive movement between the clavicle and the scapula, particularly limiting the upward displacement of the clavicle. It works in conjunction with the conoid ligament to maintain the integrity of the acromioclavicular joint.

Clinical Significance

Injuries to the trapezoid ligament can occur as part of acromioclavicular joint dislocations, commonly known as shoulder separations. These injuries are often the result of trauma, such as a fall directly onto the shoulder. The severity of the injury can vary, with more severe cases involving complete tears of the coracoclavicular ligaments.

Images

Diagram of the shoulder joint, showing the trapezoid ligament.

The coracoclavicular ligament, with the trapezoid ligament labeled.

Related Pages

• Acromioclavicular joint
• Coracoclavicular ligament
• Conoid ligament
• Shoulder anatomy

References

• Moore, K. L., Dalley, A. F., & Agur, A. M. R. (2013). Clinically Oriented Anatomy. 7th edition. Lippincott Williams & Wilkins.
• Standring, S. (2015). Gray's Anatomy: The Anatomical Basis of Clinical Practice. 41st edition. Elsevier.

• Trapezoid ligament
  Trapezoid ligament
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  Gray's Anatomy illustration 326
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