The distal epiphysis - distal extremity or end of the humerus is the triangular-shaped and widened end. The body of the humerus gradually widens towards the distal epiphysis, and the distal portion of the humerus ends with an area known as the condyle, which is formed by the trochlea, capitulum, and three fossae.

In fact, the distal end has two parts - the articular and non-articular portions. The structures of the condyle form the articular part, while the two epicondyles define the non-articular portion. The condyle articulates with the radius and the ulna, forming a synovial hinge-type joint - the elbow joint.

Overall, the distal epiphysis has the following anatomical landmarks:

Condyle - a modified articular part of the distal epiphysis; it has several anatomical features:
- Trochlea - a bony projection that is shaped like a spool and located on the anterior medial aspect of the condyle; it also extends onto the posterior aspect of the distal epiphysis, ending in the olecranon fossa; the trochlea articulates with the trochlear notch of the ulna, forming the humeroulnar joint;
- Coronoid fossa - a large hollow area that is located immediately superior to the trochlea; like the trochlea, it is also found on the anterior medial aspect of the distal epiphysis; upon the maximum flexion of the forearm, the coronoid process of the ulna lodges into this fossa;

Capitulum - a rounded and convex projection that articulates with the head of the radius; it is found on the anterior lateral aspect of the condyle lateral to the trochlea; the joint formed between the humerus and the radius is known as the humeroradial joint;
Radial fossa - another hollow area found lateral to the coronoid fossa and superior to the capitulum; it is smaller than the coronoid fossa; the radial head lodges into this fossa during maximum flexion of the forearm;
Olecranon fossa - a deep depression that is located on the posterior aspect of the distal epiphysis; it is found superior to the trochlea; the olecranon fossa is the largest of the trio; during extension of the forearm, the tip of the olecranon of the ulna lodges into this fossa; sometimes, the deepest aspect of this fossa is perforated and it has a foramen or septal aperture;
Medial epicondyle - a blunt non-articular medial projection that forms the end of the medial border of the humerus; the medial epicondyle serves as an attachment site for several structures, including the ulnar collateral ligament and many of the forearm flexor muscles (mostly the superficial muscles of the anterior compartment, such as the flexor carpi ulnaris muscle, palmaris longus muscle, flexor carpi radialis muscle, pronator teres muscle, and flexor digitorum superficialis muscle);
- Groove for the ulnar nerve - a shallow groove found on the anterior medial aspect of the distal epiphysis; it is formed between the medial epicondyle and the trochlea; it lodges the ulnar nerve;
Lateral epicondyle - a small and blunt non-articular bulge on the lateral aspect of the distal epiphysis; it is smaller than the medial epicondyle; it serves as the attachment site for several anatomical structures, including the radial collateral ligament, the supinator muscle and some of the forearm extensors (extensor digitorum muscle, extensor digiti minimi muscle, extensor carpi ulnaris muscle, and extensor carpi radialis brevis muscle).

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Humerus (distal epiphysis)