Upper Limb: Shoulder Joint lecture #1

Vocabulary flashcards covering the osteology, joints, and ligaments of the shoulder joint complex based on the lecture notes.

Pectoral (shoulder) girdle

A bony ring formed by the two scapula posteriorly and the clavicles and manubrium of the sternum anteriorly.

Facet

Any small, smooth, flat, or nearly flat surface on a bone where it articulates with another bone.

Tubercle

A small, rounded eminence or nodule found on bones, soft tissues, or organs.

Groove or sulcus

A shallow depression within the bone.

Osteology

The study of the structure and bony landmarks of the skeleton or bone.

Jugular Notch

Located on the superior surface of the manubrium between the clavicular facets, with the trachea lying just behind it.

Clavicle

Also known as the collar bone, it connects the upper limb to the trunk.

Subclavian groove

A landmark on the middle aspect of the inferior surface of the clavicle serving as the insertion point for the subclavius muscle.

Conoid tubercle

A landmark on the lateral end of the clavicle for the attachment of the conoid portion of the coracoclavicular ligament.

Trapezoid line

Located just lateral to the conoid tubercle, it is the attachment site for the trapezoid portion of the coracoclavicular ligament.

Scapula

Also known as the shoulder blade, it is a flattened triangular-shaped bone that spans between the $2nd$ and $7th$ ribs.

Glenoid labrum

A fibrocartilaginous complex that attaches as a rim to the glenoid fossa to improve the depth of the concavity.

Supraglenoid tubercle

The origin site of the long head of the biceps brachii on the scapula.

Infraglenoid tubercle

The origin site for the long head of the triceps on the scapula.

Angle of inclination (Humerus)

The orientation where the humeral head faces medially and superiorly at an angle of $135^{\circ}$.

Retroverted (Humeral head)

The humeral head orientation where it is rotated $30^{\circ}$ posteriorly relative to the medial-lateral axis through the elbow.

Greater tubercle (Humerus)

The most lateral projection of the shoulder and attachment site for the supraspinatus, infraspinatus, and teres minor muscles.

Lesser tubercle (Humerus)

Located medial to the intertubercular groove, it is the attachment site for the subscapularis muscle.

Anatomical neck (Humerus)

A groove circumscribing the head that marks the attachment of the joint capsule of the glenohumeral joint.

Surgical neck (Humerus)

The region just inferior to the greater and lesser tubercles; it is a common site for fractures.

Radial (spiral) groove

Runs obliquely across the posterior surface of the humerus, where the radial nerve and profunda brachii artery are located.

Glenohumeral (GH) Joint

Commonly known as the shoulder joint, it is a true synovial joint between the humeral head and the glenoid fossa.

Axillary pouch

The redundant inferior portion of the GH joint capsule that allows for mobility during arm elevation.

Coracoacromial ligament

The "roof of the shoulder joint" that limits superior translation of the humeral head.

Subacromial space

The space between the humeral head, acromion, and coracoacromial ligament.

Scapulothoracic Joint

Formed between the anterior concave surface of the scapula and the posterior thoracic wall; it is not a true anatomical joint.

Scapulohumeral rhythm

A $2:1$ ratio where for every $3$ degrees of shoulder elevation, $2$ degrees occur at the GHJ and $1$ degree occurs by scapulothoracic upward rotation.

Sternoclavicular (SC) Joint

A basilar, true synovial joint that is the only connection between the upper limb and the trunk.

Interclavicular ligament

Reinforces the SC joint capsule superiorly and limits superior displacement.

Avascular necrosis

Bone death due to a lack of blood supply, which can occur after a fracture of the anatomical neck of the humerus.