Sternoclavicular Joint

This article is a stub.

{{{{{quality}}}}}

Sternoclavicular Joint
Primary Type	Saddle joint"Saddle joint" is not in the list (Synovial Joint, Cartilaginous Joint, Fibrous Joint, Compound Joint) of allowed values for the "Has joint type" property., fibrocartilage."Fibrocartilage." is not in the list (Synovial Joint, Cartilaginous Joint, Fibrous Joint, Compound Joint) of allowed values for the "Has joint type" property.
Secondary Type
Bones	Manubrium, proximal clavicle"Proximal clavicle" is not in the list (Vertebra, Sacrum, Coccyx, Scapula, Clavicle, Humerus, Radius, Ulna, Scaphoid, Lunate, ...) of allowed values for the "Has joint bones" property., cartilage of first rib"Cartilage of first rib" is not in the list (Vertebra, Sacrum, Coccyx, Scapula, Clavicle, Humerus, Radius, Ulna, Scaphoid, Lunate, ...) of allowed values for the "Has joint bones" property.
Ligaments	Sternoclavicular, costoclavicular, interclavicular ligs.
Muscles
Innervation	Medial supraclavicular (C3-4) and subclavian (C5-6) nn.
Vasculature	Internal thoracic and suprascapular aa. (branches of the subclavian a.)
ROM	35° in the horizontal and coronal planes, 70° range of motion anteroposteriorly, 45° of rotation along its long axis.
Volume
Conditions	Sternoclavicular Joint Pain and Instability

The sternoclavicular joint (SCJ) is a diarthrodial, multi-axial saddle joint, and consists of the articulation between the manubrium sterni, the proximal clavicle, and the cartilage of the first rib. The articular surfaces are covered by fibrocartilage. The joint has an intraarticular disc or meniscus that is made of fibrocartilage. It is attached to the joint capsule anteriorly and posteriorly, first costal cartilage inferiorly and the clavicle superiorly.

The joint is stabilised by the following major ligaments:

Ligament	Description	Function
Sternoclavicular ligament	This consists of the anterior, posterior, superior, and inferior sternoclavicular ligaments. It attaches the manubrium sterni to the clavicle	The posterior component, provides primary anteroposterior stabilisation of the SCJ. The anterior ligament also stabilises the SCJ and prohibits excessive superior displacement
Costoclavicular ligament	Attaches the cartilage of the first rib to the clavicle	Mediates bilateral clavicle and anterior first rib stability. By anchoring the inferior surface of the sternal end of the clavicle to the first rib, it serves as the primary restraint for the SCJ.
Interclavicular ligament	Attaches the proximal end of one clavicle to the other. It also attaches to the superior manubrium sterni.	Facilitates medial traction of both clavicles

The subclavius muscle also functions to provide joint stability. There are no muscles that immediately act on the SCJ. SCJ motion primarily depends on the motion of the scapula and shoulder girdle, including the clavicle. Muscles that insert on the clavicle that influence SCJ movement are the deltoid, pectoralis major, trapezius, and sternocleidomastoid muscles.

The SCJ is only of five articulations that allow fluid shoulder girdle movement. It provides 35° range of motion for movement in the horizontal and coronal planes and 70° range of motion anteroposteriorly. It also provides 45° of rotation along its long axis. Movement of the shoulder girdle influences movement of the SCJ.

Motion	Muscles	Innervation
Elevation	levator scapulae, upper trapezius, rhomboid major and minor muscles	dorsal scapular nerve, C5 ventral ramus, C3-C4 ventral rami
Depression	pectoralis minor, lower trapezius, serratus anterior and inferior muscles	medial pectoral nerve, spinal accessory nerve, long thoracic nerve
Protraction	pectoralis minor, serratus anterior muscles	medial pectoral nerve, long thoracic nerve
Retraction	middle trapezius, latissimus dorsi, rhomboid major and minor muscles	spinal accessory nerve, thoracodorsal nerve, dorsal scapular nerve
Rotation via elevation of the glenoid cavity	upper and lower trapezius, serratus anterior and inferior muscles	suprascapular nerve, axillary nerve, long thoracic nerve
Rotation via depression of the glenoid cavity	levator scapulae, latissimus dorsi, pectoralis minor, rhomboid major and minor muscles	dorsal scapular nerve, thoracodorsal nerve, medial pectoral nerve, dorsal scapular nerve

There are several vital structures directly posterior to the SCJ. This includes the brachiocephalic trunk, internal jugular vein, common carotid artery, innominate artery and vein, vagus nerve, phrenic nerve, trachea, and oesophagus.

In a small portion of cases there is a facet that articulates with the first rib.

See Also

• Sternoclavicular Joint Pain and Instability
• Sternoclavicular Joint Injection