Medial Collateral Ligament of the Elbow
Assistant
Definition
By Gregory R. Waryasz, MD
The medial collateral ligament of the musculoskeletal system is characterized by its location and function. It is also known as the ulnar collateral ligament.
It is part of the elbow joint. It consists of fibrous dense regular connective tissue of collagen fibers.
Its unique structural feature is that it is a triangular shaped ligament that spans from the medial epicondyle of the humerus to coronoid process and olecranon of the ulna. There are three bands; anterior, posterior, and transverse.
The anterior band is cord-like and the strongest.
The posterior band is fan-like and the weakest.
The transverse band or oblique band is slender.
The medial collateral ligament as well as all other bones, muscles, and ligaments of the body are derived of mesodermal origin in the embryo.
The function of the medial collateral ligament is to resist valgus stresses.
The anterior band is the primary restraint to valgus stress.
The posterior band helps to limit flexion when contracted.
The transverse band helps to deepen the articulation surface of the trochlea of the humerus.
Common diseases include ligament tears and dislocation/subluxation.
Medial collateral ligament tears and stretches can occur as a result of physical activity including throwing in baseball. Some patients feel a “pop” with initial injury. Patients may also report numbness and tingling in the ulnar nerve distribution.
Commonly used diagnostic procedures include clinical history, physical exam, x-ray, and MRI.
It is usually treated with surgery. Physical therapy and NSAIDs are usually unsuccessful at returning athletes to throwing activities. Physical therapy and NSAIDs can be an effective treatment for returning someone to simple activities of daily living. Surgery can be performed by reconstructing the ligament with a graft.
References
Elstrom J, Virkus W, Pankovich (eds), Handbook of Fractures (3rd edition), McGraw Hill, New York, NY, 2006.
Koval K, Zuckerman J (eds), Handbook of Fractures (3rd edition), Lippincott Williams & Wilkins, Philadelphia, PA, 2006.
Lieberman J (ed), AAOS Comprehensive Orthopaedic Review, American Academy of Orthopaedic Surgeons, 2008.
Moore K, Dalley A (eds), Clinically Oriented Anatomy (5th edition), Lippincott Williams & Wilkins, Philadelphia, PA, 2006.