Ulnar collateral ligament of elbow joint

Ligament: Ulnar collateral ligament (elbow)
Left elbow-joint, showing anterior and ulnar collateral ligaments. (Ulnar collateral lig. visible at center left.)
Latin	ligamentum collaterale ulnare
Gray's	subject #84 322
From	medial epicondyle of the humerus
To	coronoid process of the ulna (anterior), olecranon (posterior)
Dorlands/Elsevier	l_09/12491985

Location of UCL injury

Pronating forearm

Supination exercise

The ulnar collateral ligament (internal lateral ligament) is a thick triangular band at the medial aspect of the elbow. It consists of two portions, an anterior and posterior united by a thinner intermediate portion. Note that this ligament is also referred to as the medial collateral ligament and should not be confused with the lateral ulnar collateral ligament (LUCL).

• The anterior portion, directed obliquely forward, is attached, above, by its apex, to the front part of the medial epicondyle of the humerus; and, below, by its broad base to the medial margin of the coronoid process.
• The posterior portion, also of triangular form, is attached, above, by its apex, to the lower and back part of the medial epicondyle; below, to the medial margin of the olecranon.

• Between these two bands a few intermediate fibers descend from the medial epicondyle to blend with a transverse band which bridges across the notch between the olecranon and the coronoid process.

• This ligament is in relation with the Triceps brachii and Flexor carpi ulnaris and the ulnar nerve, and gives origin to part of the Flexor digitorum superficialis.

Classification of the UCL injury

Ulnar collateral ligament injury can be classified into two categories a slow deterioration injury or an acute rupture. The slow and chronic deterioration can be due to repetitive stress acting on the ulna. At first, pain can be bearable and can worsen to an extent where it can terminate an athlete’s career. The repetitive stress placed on the ulna causes micro tears in the ligament resulting in the loss of structural integrity over time. The acute rupture is less common compared to the slow deterioration injury. The acute rupture occurs in collisions when the elbow is in flexion such as that in a wrestling match or a tackle in football. The ulnar collateral ligament distributes over fifty percent of the medial support of the elbow. This can result in an ulnar collateral ligament injury or a dislocated elbow causing severe damage to the elbow and the radioulnar joints.

Causes of UCL injuries

Damage to the ulnar collateral ligament is common among baseball pitchers and javelin throwers because the throwing motion is similar. Gridiron football, racquet sports, ice hockey and water polo players have also been treated for damage to the ulnar collateral ligament. Injuries to the Ulnar Collateral Ligament are believed to result from poor throwing mechanics, overuse, high throwing velocities, and throwing certain types of breaking pitches. Injuries to the Ulnar Collateral Ligament in baseball players are rarely due to one-time, traumatic events. Rather, they are more often due to small tears that accumulate over time.

Epidemiology of the UCL injury

According to the International Classification of Diseases, 9th Revision, Clinical Modification, ICD-9-CM, in 2008 the U.S. listed the diagonsis code for UCL injury as 841.1: Sprain ulnar collateral ligament. There were a total of 336 discharges of UCL injuries. Within the total discharges, separated by age groups: 18-44 year olds; 165 people (49.17%). 45-64 year olds; 91 (27.08%). 65-84 year olds, 65 (19.35%) it shows that the ulnar collateral ligament injuries were more commonly found in men than women. There were 213 men compared to 123 women with ulnar collateral ligament injury. Most of these injuries were also paid through private insurance (170: 50.63%) and Medicare (70: 20.85%). The average estimated cost for the surgery also known as Tommy John Surgery is $21,563.

Diagnosis of the UCL injury

If symptoms of an ulnar collateral ligament injury are present, one should seek a physician’s consultation in order to have a proper diagnosis. In most cases, a physician will diagnose an ulnar collateral ligament injury using a patient’s medical history and a physical examination that includes a procedure known as the valgus stress test. The valgus stress test is performed on both arms and a positive test is indicated by pain on the affected arm that is not present on the uninvolved side. Physicians often utilize imaging techniques such as musculoskeltetal ultrasound, x-rays and magnetic resonance imaging or arthroscopic surgery to aid with making a proper diagnosis.

Signs & Symptoms of the UCL injury

Pain along the inside of the elbow is the main symptom of this condition. Throwing athletes report it occurs most often during the acceleration phase of throwing. Closing the hand and clenching the fist has also been shown to reproduce the painful symptoms. The injury is often associated with an experience of a sharp “pop” in the elbow, followed by pain during a single throw. In addition, swelling and bruising of the elbow, loss of elbow range of motion, and a sudden decrease in throwing velocity are all common symptoms of a UCL injury. If the injury is not as severe, pain can be minimal with complete rest.

Grip strengthening exercises

Treatments of the UCL injury

The treatment of a UCL injury can follow the path of receiving surgical treatment or opting to not receive surgical treatment. Non surgical treatment will primarily focus on strengthening the elbow joint to regain strength and stabilize the joint. In the instance of choosing to not have the surgery, patients are instructed to follow the RICE (Rest, ice, compression, elevation) method while using NSAIDS (Non-steroidal anti-inflammatory drug) to help alleviate pain and swelling. When the swelling has subsided, individual exercises or physical therapy may be prescribed to assist in the recovery process. The goal in these instances is to strengthen the muscles around the elbow joint to compensate for the torn UCL ligament. Some of these exercises may include biceps curls (non resistance and resistance), pronating and supinating the forearm, and grip strengthening exercises. These exercises are performed with low resistance and a moderate amount of repetitions at no more than three times a week. Opting for the surgical treatment provides the possibilities of regaining the abilities to perform the overhand throwing motions most commonly associated with UCL injuries. Typically, two types of tissue may be used for the reconstructive surgery by using autograft or allograft tissues. Autograft tissue is, in most cases, the palmaris longus tendon, which is mostly seen as an accessory tendon. An allograft is when the tissue comes from a cadaver, or donor. Attachment of the new tendon is done by drilling holes known as “tunnels” in the medial epicondyle of the humerus and the sublime tubercle of the ulna. The tendon will then be laced through the tunnels in a figure eight pattern. Following the surgery, the patient may begin physical therapy shortly after.

See also

• Tommy John surgery

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.