Articulations of the Upper Extremity: Difference between revisions

Latest revision as of 14:36, 30 March 2025

Editor-In-Chief: Prab R Tumpati, MD
Obesity, Sleep & Internal medicine
Founder, WikiMD Wellnesspedia &
W8MD's medical weight loss NYC, sleep center NYC
Philadelphia medical weight loss and Philadelphia sleep clinics
Anatomy > Gray's Anatomy of the Human Body > III. Syndesmology > 6. Articulations of the Upper Extremity > a. Sternoclavicular joint

Henry Gray (1821–1865). Anatomy of the Human Body. 1918.

Sternoclavicular Articulation[edit]

(Articulatio sternoclavicularis)

File:Gray325.png

Anterior view of the sternoclavicular joint.

File:Gray326.png

Shoulder joint showing ligamentous attachments.

File:Pectoral girdle front diagram.svg

Bones of the shoulder girdle (not from Grays)

The sternoclavicular joint is a synovial joint of the double arthrodial type, connecting the upper limb to the axial skeleton. It is the only true joint between the upper limb and the trunk.

This articulation is formed by the junction of three components:

The sternal end of the clavicle
The manubrium of the sternum
The cartilage of the first rib

Despite the disparity in size between the articular surfaces (the clavicle being significantly larger), stability is achieved through a fibrocartilaginous articular disk and a robust set of ligaments.

Joint Structures[edit]

Articular Capsule[edit]

The capsular ligament completely encloses the joint. It is strong anteriorly and posteriorly, where it blends with the anterior and posterior sternoclavicular ligaments. Superiorly and inferiorly, the capsule is thinner and more areolar in character.

Articular Disk[edit]

The articular disk is a fibrocartilaginous structure interposed between the clavicle and the sternum. It is nearly circular in shape and divides the joint into two separate synovial cavities. It is:

Attached superiorly to the posterior superior aspect of the clavicle’s articular surface
Attached inferiorly to the cartilage of the first rib
Circumferentially continuous with the capsule and ligaments

This disk allows for increased range of motion and contributes significantly to joint stability.

Ligaments[edit]

Anterior Sternoclavicular Ligament[edit]

(Ligamentum sternoclaviculare anterius)

This ligament reinforces the front of the joint capsule. It passes obliquely from the anterosuperior sternal end of the clavicle to the anterior surface of the manubrium. It is crossed superficially by the sternal head of sternocleidomastoid.

Posterior Sternoclavicular Ligament[edit]

(Ligamentum sternoclaviculare posterius)

Located posteriorly, this ligament extends from the posterosuperior clavicle to the posterior manubrium. It lies anterior to the sternohyoid and sternothyroid muscles.

Interclavicular Ligament[edit]

(Ligamentum interclaviculare)

A transverse band connecting the superior aspects of both clavicles and the superior border of the manubrium. It spans the jugular notch and helps resist downward displacement of the clavicles.

Costoclavicular Ligament[edit]

(Ligamentum costoclaviculare; rhomboid ligament)

This short, strong ligament runs obliquely between the costal tuberosity of the clavicle and the superior surface of the first rib’s costal cartilage. It limits elevation of the clavicle and plays a key role in joint stabilization. It lies anterior to the subclavian vein and posterior to the subclavius muscle.

Synovial Membranes[edit]

Two distinct synovial membranes are present:

The lateral synovial membrane — between the clavicle and the articular disk
The medial synovial membrane — between the sternum and the articular disk

The medial membrane is usually larger.

Movements[edit]

The sternoclavicular joint permits motion in multiple directions:

Elevation and depression – occurs primarily between the clavicle and the articular disk.
Protraction and retraction – the clavicle and disk glide over the sternum.
Circumduction – a composite movement involving the above motions.

The joint acts as a pivot point for scapular movement, indirectly enabling shoulder motion.

Muscles Involved[edit]

Elevation: Trapezius (upper fibers), levator scapulae, sternocleidomastoid (clavicular head)
Depression: Gravity, subclavius, pectoralis minor, lower fibers of trapezius
Protraction: Serratus anterior, pectoralis minor
Retraction: Rhomboids, middle fibers of trapezius

Ligamentous Constraints[edit]

Elevation is limited by the costoclavicular ligament
Depression is limited by the interclavicular ligament and the articular disk
Protraction and retraction are checked by the anterior and posterior sternoclavicular ligaments

Clinical Relevance[edit]

While rare, dislocations of the sternoclavicular joint can occur due to trauma. Posterior dislocations are particularly dangerous due to the proximity of mediastinal structures. Degenerative changes may also affect the joint with age or repetitive stress.

Gray's Anatomy[edit]

Anatomy atlases (external)[edit]

[1] - Anatomy Atlases

Adapted from the Classic Grays Anatomy of the Human Body 1918 edition (public domain)

@@ Line 1: / Line 1: @@
-[[Anatomy]] > [[Gray's Anatomy| Gray's Anatomy of the Human Body]] > III. Syndesmology > 6. Articulations of the Upper Extremity. a. Sternoclavicular Articulation
+{{SI}}
+[[Anatomy]] > [[Gray's Anatomy|Gray's Anatomy of the Human Body]] > III. Syndesmology > 6. Articulations of the Upper Extremity > a. [[Sternoclavicular joint]]
-[[Henry Gray]] (1821–1865).  Anatomy of the Human Body.  1918.
+[[Henry Gray]] (1821–1865). ''Anatomy of the Human Body''. 1918.
-'''6. Articulations of the Upper Extremity. a. Sternoclavicular Articulation'''
+== '''Sternoclavicular Articulation''' ==
+''(Articulatio sternoclavicularis)''
+[[File:Gray325.png|Anterior view of the sternoclavicular joint.|thumb]]
+[[File:Gray326.png|Shoulder joint showing ligamentous attachments.|thumb]]
+[[File:Pectoral girdle front diagram.svg|Bones of the [[shoulder girdle]] (not from Grays)|thumb]]
-The articulations of the Upper Extremity may be arranged as follows:
+The '''sternoclavicular joint''' is a [[synovial joint]] of the [[arthrodial joint|double arthrodial]] type, connecting the upper limb to the axial skeleton. It is the only true joint between the [[upper limb]] and the [[trunk]].
-*I. Sternoclavicular.
+This articulation is formed by the junction of three components:
-*II. Acromioclavicular.
-*III. Shoulder.
-*IV. Elbow.
-*V. Radioulnar.
-*VI. Wrist.
-*VII. Intercarpal.
-*VIII. Carpometacarpal.
-*IX. Intermetacarpal.
-*X. Metacarpophalangeal.
-*XI. Articulations of the Digits.
-'''Sternoclavicular Articulation (Articulatio Sternoclavicularis) (Fig. 325)'''
+* The sternal end of the [[clavicle]]
+* The [[manubrium]] of the [[sternum]]
+* The cartilage of the [[first rib]]
-The sternoclavicular articulation is a double arthrodial joint. The parts entering into its formation are the sternal end of the clavicle, the upper and lateral part of the manubrium sterni, and the cartilage of the first rib. The articular surface of the clavicle is much larger than that of the sternum, and is invested with a layer of cartilage,  68 which is considerably thicker than that on the latter bone. The ligaments of this joint are:
+Despite the disparity in size between the articular surfaces (the clavicle being significantly larger), stability is achieved through a fibrocartilaginous [[articular disk]] and a robust set of ligaments.
-#The Articular Capsule.
+== '''Joint Structures''' ==
-#The Interclavicular.
-#The Anterior Sternoclavicular.
-#The Costoclavicular.
-#The Posterior Sternoclavicular.
-#The Articular Disk.
-The Articular Capsule (''[[capsula articularis; capsular ligament]]'') — The articular capsule surrounds the articulation and varies in thickness and strength. In front and behind it is of considerable thickness, and forms the anterior and posterior sternoclavicular ligaments; but above, and especially below, it is thin and partakes more of the character of areolar than of true fibrous tissue.
+=== Articular Capsule ===
+The '''[[capsular ligament]]''' completely encloses the joint. It is strong anteriorly and posteriorly, where it blends with the anterior and posterior sternoclavicular ligaments. Superiorly and inferiorly, the capsule is thinner and more areolar in character.
-The Anterior Sternoclavicular Ligament (''[[ligamentum sternoclaviculare anterior]]'') — The anterior sternoclavicular ligament is a broad band of fibers, covering the anterior surface of the articulation; it is attached ''[[above]]'' to the upper and front part of the sternal end of the clavicle, and, passing obliquely downward and medialward, is attached below to the front of the upper part of the manubrium sterni. This ligament is covered by the sternal portion of the Sternocleidomastoideus and the integument; ''[[behind]]'' it is in relation with the capsule, the articular disk, and the two synovial membranes.
+=== Articular Disk ===
+The '''[[articular disk]]''' is a fibrocartilaginous structure interposed between the clavicle and the sternum. It is nearly circular in shape and divides the joint into two separate synovial cavities. It is:
-'''The Posterior Sternoclavicular Ligament (''[[ligamentum sternoclaviculare posterius]]'')'''—The posterior sternoclavicular ligament is a similar band of fibers, covering the posterior surface of the articulation; it is attached above to the upper and back part of the sternal end of the clavicle, and, passing obliquely downward and medialward, is fixed below to the back of the upper part of the manubrium sterni. It is in relation, in ''[[front]]'' with the articular disk and synovial membranes; ''[[behind]]'' with the Sternohyoideus and Sternothyreoideus.
+* Attached ''superiorly'' to the posterior superior aspect of the clavicle’s articular surface
+* Attached ''inferiorly'' to the cartilage of the first rib
+* Circumferentially continuous with the capsule and ligaments
-The Interclavicular Ligament (''[[ligamentum interclaviculare]]'') — This ligament is a flattened band, which varies considerably in form and size in different individuals, it passes in a curved direction from the upper part of the sternal end of one clavicle to that of the other, and is also attached to the upper margin of the sternum. It is in relation, in ''[[front]]'' with the integument and Sternocleidomastoidei; ''[[behind]]'' with the Sternothyreoidei.
+This disk allows for increased range of motion and contributes significantly to joint stability.
-'''The Costoclavicular Ligament (''[[ligamentum costoclaviculare; rhomboid ligament]]'')'''—This ligament is short, flat, strong, and rhomboid in form. Attached below to the upper and medial part of the cartilage of the first rib, it ascends obliquely backward and lateralward, and is fixed above to the costal tuberosity on the under surface of the clavicle. It is in relation, in ''[[front]]'' with the tendon of origin of the Subclavius; ''[[behind]]'' with the subclavian vein.
+== '''Ligaments''' ==
-[[File:Gray325.png|thumb|FIG. 325– Sternoclavicular articulation. Anterior view. (''Picture From the Classic Gray's Anatomy'')]]
+=== Anterior Sternoclavicular Ligament ===
+''(Ligamentum sternoclaviculare anterius)''
-The Articular Disk (''[[discus articularis]]'') — The articular disk is flat and nearly circular, interposed between the articulating surfaces of the sternum and clavicle. It is attached, ''[[above]]'' to the upper and posterior border of the articular surface of the clavicle; ''[[below]]'' to the cartilage of the first rib, near its junction with the sternum; and by its circumference to the interclavicular and anterior and posterior sternoclavicular ligaments. It is thicker at the circumference, especially its upper and back part, than at its center. It divides the joint into two cavities, each of which is furnished with a synovial membrane.
+This ligament reinforces the front of the joint capsule. It passes obliquely from the anterosuperior sternal end of the clavicle to the anterior surface of the manubrium. It is crossed superficially by the [[sternal head of sternocleidomastoid]].
-'''[[Synovial Membranes]]'''—Of the two synovial membranes found in this articulation, the lateral is reflected from the sternal end of the clavicle, over the adjacent surface of the articular disk, and around the margin of the facet on the cartilage of the first rib; the medial is attached to the margin of the articular surface of the sternum and clothes the adjacent surface of the articular disk; the latter is the larger of the two.
+=== Posterior Sternoclavicular Ligament ===
+''(Ligamentum sternoclaviculare posterius)''
-'''[[Movements]]'''—This articulation admits of a limited amount of motion in nearly every direction—upward, downward, backward, forward, as well as circumduction. When these movements take place in the joint, the clavicle in its motion carries the scapula with it, this bone gliding on the outer surface of the chest. This joint therefore forms the center from which all movements of the supporting arch of the shoulder originate, and is the only point of articulation of the shoulder girdle with the trunk. The movements attendant on elevation and depression of the shoulder take place between the clavicle and the articular disk, the bone rotating upon the ligament on an axis drawn from before backward through its own articular facet; when the shoulder is moved forward and backward, the clavicle, with the articular disk rolls to and fro on the articular surface of the sternum, revolving, with a sliding movement, around an axis drawn nearly vertically through the sternum; in the circumduction of the shoulder, which is compounded of these two movements, the clavicle revolves upon the articular disk and the latter, with the clavicle, rolls upon the sternum.
+Located posteriorly, this ligament extends from the posterosuperior clavicle to the posterior manubrium. It lies anterior to the [[sternohyoid]] and [[sternothyroid]] muscles.
-Elevation of the shoulder is limited principally by the costoclavicular ligament; depression, by the interclavicular ligament and articular disk. The muscles which ''[[raise]]'' the shoulder are the upper fibers of the Trapezius, the Levator scapulæ, and the clavicular head of the Sternocleidomastoideus, assisted to a certain extent by the Rhomboidei, which pull the vertebral border of the scapula backward and upward and so raise the shoulder. The ''[[depression]]'' of the shoulder is principally effected by gravity assisted by the Subclavius, Pectoralis minor and lower fibers of the Trapezius. The shoulder is drawn ''[[backward]]'' by the Rhomboidei and the middle and lower fibers of the Trapezius, and ''[[forward]]'' by the Serratus anterior and Pectoralis minor.
+=== Interclavicular Ligament ===
+''(Ligamentum interclaviculare)''
-'''Note 68'''  According to Bruch, the sternal end of the clavicle is covered by a tissue which is fibrous rather than cartilaginous in structure.
+A transverse band connecting the superior aspects of both clavicles and the superior border of the manubrium. It spans the jugular notch and helps resist downward displacement of the clavicles.
-{{grays}}
+=== Costoclavicular Ligament ===
+''(Ligamentum costoclaviculare; rhomboid ligament)''
+This short, strong ligament runs obliquely between the costal tuberosity of the clavicle and the superior surface of the first rib’s costal cartilage. It limits elevation of the clavicle and plays a key role in joint stabilization. It lies anterior to the [[subclavian vein]] and posterior to the [[subclavius]] muscle.
+== '''Synovial Membranes''' ==
+Two distinct synovial membranes are present:
+* The '''lateral synovial membrane''' — between the clavicle and the articular disk
+* The '''medial synovial membrane''' — between the sternum and the articular disk
+The medial membrane is usually larger.
+== '''Movements''' ==
+The sternoclavicular joint permits motion in multiple directions:
+* '''Elevation and depression''' – occurs primarily between the clavicle and the articular disk.
+* '''Protraction and retraction''' – the clavicle and disk glide over the sternum.
+* '''Circumduction''' – a composite movement involving the above motions.
+The joint acts as a pivot point for scapular movement, indirectly enabling shoulder motion.
+=== Muscles Involved ===
+* '''Elevation:''' [[Trapezius]] (upper fibers), [[levator scapulae]], [[sternocleidomastoid]] (clavicular head)
+* '''Depression:''' Gravity, [[subclavius]], [[pectoralis minor]], lower fibers of trapezius
+* '''Protraction:''' [[Serratus anterior]], [[pectoralis minor]]
+* '''Retraction:''' [[Rhomboids]], middle fibers of [[trapezius]]
+=== Ligamentous Constraints ===
+* '''Elevation''' is limited by the [[costoclavicular ligament]]
+* '''Depression''' is limited by the [[interclavicular ligament]] and the articular disk
+* '''Protraction and retraction''' are checked by the anterior and posterior sternoclavicular ligaments
+== '''Clinical Relevance''' ==
+While rare, dislocations of the sternoclavicular joint can occur due to trauma. Posterior dislocations are particularly dangerous due to the proximity of mediastinal structures. Degenerative changes may also affect the joint with age or repetitive stress.
+== '''See Also''' ==
+* '''[[Clavicle]]'''
+* '''[[Sternum]]'''
+* '''[[Shoulder girdle]]'''
+* '''[[Pectoral girdle]]'''
+* '''[[Acromioclavicular joint]]'''
+* '''[[Upper limb anatomy]]'''
+{{Human anatomical features}}
+{{Bones of upper extremity}}
+{{Joints of upper limbs}}
+{{Grays adapted}}
+[[Category:Upper limb anatomy]]
+[[Category:Joints]]
+[[Category:Shoulder girdle]]