Elbow Throwing Injuries: The Medial Collateral Ligament (MCL) and Tommy John Surgery

An Interview with Dr. David Altchek

In most people, major elbow injuries are rarely caused by stressing the joint during a throwing motion. But for serious amateur and professional baseball pitchers who may throw a ball between 70 to 100 miles an hour, each pitch places a high level of force on the elbow joint. Over time, this repetitive motion can lead to inflammation (swelling), cartilage injuries, bone spurs and, eventually, a tear in the medial collateral ligament (MCL) of the elbow. This ligament, sometimes referred to as the ulnar collateral ligament (UCL), should not be confused with the MCL of the knee.

The MCL of the elbow is part of a complex of ligaments and tendons that attach and stabilize the bones of the lower and upper arm where they meet at the joint. Specifically, the MCL attaches the ulna (which, along with the radius, makes up the bones of the lower arm) to the humerus, the bone of the upper arm. When you tear your MCL, you will still have a full range of motion in the joint and the ability to throw, but will not be able to exert significant force. MCL tears of the elbow are often the result of a gradual process of "attenuation" (weakening) of the ligament. In some cases, it may not be immediately clear that the ligament has been torn. In others, people report hearing a pop at the time of injury.

Image: Illustration of the medial collateral ligament (MCL) of the elbow.

Fortunately, the surgical treatment of MCL tears commonly known as "Tommy John surgery" – so named for professional baseball player Thomas ("Tommy") Edward John Jr., who became the first pitcher to have this treatment – is highly successful. It can help professional and amateur athletes alike to return to their sports.

The surgery, formally known as ulnar collateral ligament reconstruction was developed by Dr. Frank Jobe, then the team physician for the Los Angeles Dodgers baseball team. In 1974, he used this technique to repair the MCL in Tommy John's left arm. Since then, hundreds of athletes have undergone the procedure, in which a tendon is taken from another part of the body and grafted to replace the injured ligament. The most common tendon source is one that connects the palmaris longus muscle of the forearm to the fascia of the palm in the hand. This tendon is visible in most people at the wrist when a fist is made. A common second choice is the accessory hamstring tendon in the leg.

Photo showing the transverse carpal ligament that connects the palmaris longus muscle to the palmar fascia of the hand.
Palmaris longus

"Before Dr. Jobe developed this surgical technique, an MCL tear was often a career-ending injury," says David W. Altchek, MD, Attending Orthopedic Surgeon and Co-Chief Emeritus in the Sports Medicine Shoulder Service. "Today, athletes that undergo MCL reconstruction often play as well as they did before the surgery, and, in some cases even better." Nonathletes may also develop a full or partial tear of the MCL, Dr. Altchek says. But these patients usually don't require surgery because their less strenuous activities are not generally affected.

Today, athletes with MCL tears can benefit from refinements to Dr. Jobe's techniques that have been developed by Dr. Altchek and his colleagues at HSS. Dr. Altchek begins treatment with an arthroscopic examination of the affected area. (For more information on elbow arthroscopy, please see the article on this topic listed below.)

After addressing any other conditions that are present in the joint, such as bone spurs, the orthopedic surgeon makes an incision to reveal the medial aspect (inner side) of the elbow joint. If possible, the surgeon then reattaches the remaining portion of the MCL. The harvested tendon graft is threaded through holes created in the ulna and humerus and sutured to stabilize the joint.

An illustration showing the insertion of the tendon graft in Tommy John surgery.
Illustration showing insertion of the tendon graft

Dr. Altchek's technique differs from Dr. Jobe's in that only one hole is made in the humerus bone, versus the three holes Dr. Jobe used in his original operation. This provides increased protection to the bone, which is more vulnerable to fractures if it has multiple holes in it. Dr. Altchek also found a way to simplify the tensioning of the graft and developed a special stitch that provides more secure fixation of the tendon to the bone.

In the original Tommy John procedure, the orthopedic surgeon took off the overlying muscles and moved the nerve away from the joint to reduce the chance of injury. However, this approach still ran a risk of trauma to both muscles and nerves. Today, orthopedic surgeons can use a safer, muscle-splitting technique that minimizes trauma to the muscles. Also, in most cases, when Dr. Altchek performs the surgery he finds it necessary to move the ulnar nerve.

The newer technique also takes less time, making it a safer surgery. Traditionally, MCL reconstruction took about four hours. It can now be completed in about a half hour, which reduces the chance of infection. Recovery from MCL reconstruction can take a long time. The patient must wait 9 to 12 months for the ligament to be healed into the bone before returning full sports activity. During that period, he or she will participate in a rehabilitation (physical therapy) program in which an increasing amount of force is gradually applied to the elbow, and the muscles are strengthened. Most athletes can return to competitive play in about a year.

Results of the surgery are generally excellent. In one study where Dr. Altchek used his modified Tommy John technique, 30 out of 31 patients returned to their previous level of competition over an 11-month period.

While the incidence of MCL tears is high among elite major league baseball pitchers, Dr. Altchek points out that this is not the only population that experiences the injury. Female softball players who play the position of catcher or short stop are prone to elbow MCL tears. Javelin throwers, lacrosse and tennis players, and golfers are also vulnerable. This is especially true for people middle-aged or older, who may have some long-term degeneration of the ligament. In addition, children who participate in little league may injure the ligament. Elbow MCL tears are less common in children and teenagers than in adults because they do not throw as hard as, and their ligaments are more elastic than in adults. But they do occur sporadically. Treatment in children and adolescents may be slightly different than for adults, out of concern to protect the growth plate in the joint.

Summary Prepared by Nancy Novick *Illustration of (MCL) provided courtesy of Bartleby.com


Headshot of David W. Altchek, MD
David W. Altchek, MD
Attending Orthopedic Surgeon, Hospital for Special Surgery
Co-Chief Emeritus, Sports Medicine, Hospital for Special Surgery

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