Bony Landmarks
This lateral projection of the scapula articulates with the clavicle at the acromioclavicular joint.
What is the acromion?
This joint connects the sternum to the clavicle and is the only bony articulation between the upper limb and axial skeleton.
What is the sternoclavicular joint?
This muscle forms the rounded contour of the shoulder and is responsible for abduction of the arm past 15 degrees.
What is the deltoid?
This nerve runs along the posterior aspect of the humerus in the radial groove and can be injured in a midshaft humeral fracture.
What is the radial nerve?
This bony landmark on the scapula serves as the attachment site for the short head of the biceps brachii and coracobrachialis.
What is the coracoid process?
This ligament prevents superior displacement of the humeral head by forming an arch over the glenohumeral joint.
What is the coracoacromial ligament?
This muscle of the brachium has two heads and is a powerful supinator of the forearm.
What is the biceps brachii?
This nerve, which passes through the suprascapular notch, is responsible for innervating two of the four rotator cuff muscles.
What is the suprascapular nerve?
This groove separates the greater and lesser tubercles of the humerus and contains the tendon of the long head of the biceps brachii.
What is the intertubercular (bicipital) groove?
This ligament wraps around the head of the radius and allows for pronation and supination while maintaining articulation with the ulna.
What is the annular ligament?
This large, fan-shaped muscle originates from the clavicle and sternum and inserts on the intertubercular groove of the humerus.
What is the pectoralis major?
The medial and lateral pectoral nerves innervate these two muscles, with the medial pectoral nerve uniquely piercing one of them.
What are the pectoralis major and pectoralis minor?
This notch on the ulna articulates with the trochlea of the humerus, forming part of the elbow joint.
What is the trochlear notch?
This fibrocartilaginous structure deepens the glenoid fossa, increasing stability of the glenohumeral joint.
What is the glenoid labrum?
This deep muscle, often overlooked in shoulder stabilization, originates from the ribs and inserts on the medial border of the scapula, aiding in protraction.
What is the serratus anterior?
The musculocutaneous nerve innervates all of the muscles in this arm compartment.
What is the anterior compartment of the arm (biceps brachii, brachialis, and coracobrachialis)?
This concave surface on the scapula houses the head of the humerus, forming the glenohumeral joint.
What is the glenoid fossa (or glenoid cavity)?
This ligament runs from the coracoid process to the humerus and helps support the superior glenohumeral joint capsule.
What is the coracohumeral ligament?
This muscle assists the latissimus dorsi in shoulder extension, adduction, and internal rotation but is not part of the rotator cuff.
What is the teres major?
This nerve courses through the quadrangular space and is at risk in shoulder dislocations.
What is the axillary nerve?