Common flexor tendon
Pronator teres muscle
| Origin | humeral head: medial epicondyle of humerus (common flexor tendon) ulnar head: coronoid process of ulna |
| Insertion | Middle of the lateral surface of the body of the radius |
| Artery | ulnar artery and radial artery |
| Nerve | median nerve |
| Actions | pronation of forearm, flexes elbow |
Anconeus muscle
| Origin | lateral epicondyle of the humerus proximally |
| Insertion | lateral surface of the olecranon process and the superior part of the posterior ulna distally |
| Artery | deep brachial artery, recurrent interosseous artery |
| Nerve | radial nerve (C7, C8, and T1) |
| Actions | It is partly blended in with the triceps, which it assists in extension of the forearm. It also stabilizes the elbow during pronation and supination and pulls slack out of the elbow joint capsule during extension to prevent impingement. |
Triceps brachii muscle
| Origin | long head: infraglenoid tubercle of scapula lateral head: above the radial sulcus medial head: below the radial sulcus |
| Insertion | olecranon process of ulna |
| Artery | deep brachial artery (Profunda brachii) |
| Nerve | radial nerve and axillary nerve (long head) |
| Actions | extends forearm, long head extends shoulder |
Teres minor muscle
| Origin | lateral border of the scapula |
| Insertion | inferior facet of greater tubercle of the humerus |
| Artery | posterior circumflex humeral artery and the circumflex scapular artery |
| Nerve | axillary nerve |
| Actions | laterally rotates the arm, adducts the forearm, stabilizes humerus |
Infraspinatus muscle
| Origin | infraspinous fossa of the scapula |
| Insertion | middle facet of greater tubercle of the humerus |
| Artery | suprascapular and circumflex scapular arteries |
| Nerve | suprascapular nerve |
| Actions | Lateral rotation of arm and stabilizes humerus |
