The costoclavicular ligament or rhomboid ligament (a.k.a. Halsted's ligament ) is the major stabilizing factor of the sternoclavicular joint and is the axis of movement of the joint.
The costoclavicular ligament binds the inferior medial clavicle (via the rhomboid fossa) to the first costal cartilage and the adjacent end of the first rib. It is composed of an anterior lamina and posterior lamina which are usually separated by a bursa.
- anterior lamina
- origin: anterior lip of the ligamentous impression (rhomboid fossa) on the clavicle
- insertion: runs downward and medially to the first costal cartilage
- posterior lamina
- origin: posterior lip of the ligamentous impression (rhomboid fossa) on the clavicle
- insertion: runs downward and laterally to the adjacent end of the first rib
The rhomboid fossa may be prominent and simulate a lytic lesion (see case 1).