Fracture of the proximal 1/3 of the ulna with an associated radial head dislocation.
Mechanisms of injury include direct blow, hyperpronation and hyperextension.
Radial head is dislocated anteriorly in 60% of the cases.
can be associated with Posterior Interosseous Nerve (PIN) palsy.
PIN is the deep motor branch of the radial nerve and supplies the wrist extensors except for Extensor Carpi radialis Longus. The palsy can be delayed so be sure to document wrist extenson strength.
Most patients will require operative repair of the ulna fracture.
Splint the forearm in neutral rotation with slight supination, keeping the elbow flexed at 90 degrees.
References
Wheeless' Textbook of Orthopaedics http://www.wheelessonline.com/ortho/monteggias_fracture
