Anatomy of Clavicle and Scapula

Study Notes

Long bone connecting the sternum (breastbone) to the scapula (shoulder blade)
Helps transfer weight and facilitate movement
Triangular shape, with anterior convexity allowing structures to pass from neck to upper limb.
Articulates with the acromion of the scapula laterally and the sternum medially, forming the acromioclavicular and sternoclavicular joints.
Key features include: conoid tubercle for ligament attachment, and anterior and posterior areas for ligament attachments.

Large, flat, triangular bone in the upper back.
Key features include: superior, medial, and lateral borders.
Key features include: superior, inferior, and lateral angles.
Surfaces include the subscapular fossa, offering muscle attachment sites, and a posterior surface with the supraspinous and infraspinous fossae, for muscle attachment.
Processes include the acromion, contributing to the shoulder joint, and the coracoid process, providing attachment for muscles and ligaments.
Glenoid cavity located at the lateral angle articulates with the head of the humerus forming the shoulder joint.

Long bone, the largest bone in the upper limb.
Major bony prominences include greater and lesser tubercles, serving as muscle attachments for rotator cuff muscles.
Deltoid tuberosity supports the deltoid muscle.
Anatomical neck distinguishes the head from the shaft, while the surgical neck is a more fragile portion prone to fractures.
Intertubercular sulcus (bicipital groove) provides space for the tendon of the biceps brachii muscle.

Large, triangular shoulder muscle.
Originates from the clavicle, acromion, and spine of the scapula.
Insertions are on the deltoid tuberosity.
Innervated by the axillary nerve.
Functions include arm abduction, flexion, and extension, and external and internal rotation.

Group of four muscles crucial for shoulder stability and movement.
Include supraspinatus, infraspinatus, teres minor, and subscapularis.
Each has specific origins, insertions, innervations, and functions related to shoulder joint movement.

Large, superficial muscle of the upper back and neck resembling a trapezoid.
Originates from the occipital bone, nuchal ligament, and the spinous processes of the thoracic vertebrae.
Inserts into the clavicle, acromion, and spine of the scapula.
Innervated by the accessory nerve.
Three parts function in elevating, retracting, and depressing/rotating the scapulae.

Elongated muscle situated on the side of the neck.
Originates from the transverse processes of C1-C4 vertebrae.
Inserts into the medial border of the scapula, specifically from the superior angle to the root of the scapular spine.
Innervated by the dorsal scapular nerve, and cervical spinal nerves C3 and C4.
Functions include elevating the scapula, laterally tilting the neck, and fixing the cervical vertebrae.

Located deep to the trapezius muscle, assisting with scapular movement.
Originate from the spinous processes of the thoracic vertebrae (major) or cervical vertebrae (minor).
Insert into the medial border of the scapula.
Innervated by the dorsal scapular nerve.
Functions in retracting and downwardly rotating the scapulae.

Large, flat, broad muscle on the lower back.
Originates from the spinous processes of inferior thoracic vertebrae, lower ribs, lumbar spine, iliac crest, and thoracolumbar fascia.
Inserts into the intertubercular groove of the humerus.
Innervated by the thoracodorsal nerve (C6, C7, C8).
Functions in extending, adducting, and medially rotating the arm.

Located beneath the pectoralis major, a smaller triangular muscle.
Originates from the ribs 3-5.
Inserts into the coracoid process of the scapula.
Innervated by the medial and lateral pectoral nerves.
Functions in stabilizing the scapula, assisting with shoulder flexion and medial rotation and preventing excessive upward movement of the arm.

Small muscle situated beneath the clavicle.
Originates from the first rib.
Inserts into the inferior surface of the clavicle.
Innervated by the subclavian nerve.
Functions to depress and stabilize the sternoclavicular joint and prevent the excessive upward movement of the shoulder.