Extensor carpi radialis brevis muscle — lateral epicondyle

Extensor carpi ulnaris muscle — lateral epicondyle (and also to the posterior border of the ulna

Extensor digiti minimi muscle — lateral epicondyle

Extensor digitorum muscle — lateral epicondyle

Supinator muscle — lateral epicondyle (and also to the radial collateral ligament, annular ligament, the supinator fossa, and the crest of the ulna )

Flexor carpi radialis muscle — medial epicondyle

Flexor carpi ulnaris muscle, its humeral head — medial epicondyle

Flexor digitorum superficialis muscle, its humeroulnar head — medial epicondyle (and also to the ulnar collateral ligament and the coronoid process of the ulna )

Palmaris longus muscle — medial epicondyle

Pronator teres muscle — medial epicondyle (and also to the coronoid process of the ulna)

Sorry that was super technical, got it from wikipedia.

The gist of it is that the two condyles are the medial and lateral condyles, the list above shows what muscles attach to them. The medial epicondyle is on the inside of the elbow, the lateral is on the outside.