The Elbow

Anatomy
The cubital tunnel is an osteofibrous tunnel formed by

• the medial epicondyle - medial
• the ulnar collateral ligament at the bottom of the tunnel
• olecranon - lateral
• arcuate ligament roof of the tunnel.
  This arcuate ligament is the fibrous arcade that connects the ulnar and humeral heads of the flexor carpi ulnaris

Biomechanics

1. The volume in the cubital tunnel is reduced with elbow flexion which may result in external compression of the ulnar nerve:
   • The arcuatum ligament stretches and comes under tension (olecranon moves away from medial epicondyle)
   • The ulnar collateral ligament relaxes and bulges slightly with flexion.
2. The Ulnar nerve elongates and is moved medially during flexion. This may result in subluxation and friction-neuropathy