Medial Collateral Ligament Injury
(More formally called Ulnar Collateral Ligament Injury)
What is a Medial Collateral Ligament Injury?
Ligaments are soft tissue structures that connect bones to bones across a joint. The best way to think of a ligament is as a tether between the bones, which gets tight when the joint moves. When a ligament is torn, the tether is too long and the joint becomes unstable. This can lead to pain, a sense of instability or looseness, and inability to work or do a sport.
In the elbow, the two ligaments primarily responsible for maintaining elbow stability are the Medial Collateral Ligament (more formally called the Ulnar Collateral Ligament), and the Lateral Ulnar Collateral Ligament. The Medial Collateral Ligament (MCL) is located on the inside of the elbow close to the body, and the Lateral Ulnar Collateral Ligament (LUCL) is located on the outside of the elbow away from the body. The MCL is a thick fan-shaped band of ligamentous tissue connecting the humerus (the upper arm bone), and the ulna (the bone of the forearm on the opposite side of the thumb). The MCL complex is composed of three bundles or bands—the anterior, posterior, and transverse bands. Of the three bands, the anterior band of the MCL is the arm’s primary restraint from stress to the elbow, while the posterior and transverse band also help to stabilize the elbow.
The bands of the MCL can tear or rupture during an acute elbow injury or dislocation, or from repetitive stress and overuse. The largest stresses in the elbow are those forces that cause twisting and bending of the elbow, such as the throwing of a baseball or javelin. Football, tennis, ice hockey, and water polo players are also especially prone to MCL injuries as the motions of these athletes put extreme stress on the ligament during certain parts of the motion. The MCL can become stretched, frayed, or torn through the stress of repetitive throwing motion. If the force on the soft tissues is greater than the tensile strength of the structure, then tiny tears of the ligament can develop. Months (and even years) of throwing cause a process of microtears, degeneration, and eventually, rupture of the medial collateral ligament. The athlete may report the injury occurred during a single throw, but the reality is usually that the ligament finally became weakened to the point of rupture over time.
Signs and Symptoms:
Pain along the inside of the elbow is the main symptom of Medial Collateral Ligament injury. Throwing athletes often report pain primarily during the acceleration phase of throwing. If loose fragments or uneven joint surfaces exist, you may notice popping, catching, or grinding.
Sometimes swelling can be seen along the inside of the elbow. There also may be bruising in the area, especially with a MCL rupture. Some patients experience a slight loss of elbow motion. Closing the hand and clenching the fist reproduces the painful symptoms.
The goals of nonsurgical treatment of a torn MCL are to restore stability to the elbow joint and to provide pain relief to the patient. Treatment consists of an initial period of rest with non-steroidal anti-inflammatory medications and application of ice to the elbow daily until the pain and swelling are gone. After inflammation of the elbow has decreased, the patient may begin physical therapy. The purpose of physical therapy is to strengthen the muscles around the elbow to compensate for the torn ligament.
If the patient wishes to return to strenuous overhead or throwing activities and they do not respond to non–surgical treatments, surgical repair of the MCL may be recommended.
When the condition fails to respond to the conservative care described above, surgery may be indicated. If pain is the primary symptom and there is no evidence that the elbow joint is grossly unstable, the surgeon may use an arthroscope (tiny camera) to look inside the elbow and see the condition of the joint and the soft tissue. The surgeon may perform Arthroscopic Debridement of any tissue fragments or frayed edges. During debridement the surgeon carefully cleans the area by removing any loose cartilage or damaged tissue. Any bone spurs or areas of calcium build-up are also removed.
If arthroscopic debridement does not help the symptoms, further surgical care may be required. There are two types of surgery – 1) Repair the existing ligament or 2) Reconstruction (replacement) of the ligament.
1) MCL Repair:
If it is an acute MCL injury (within 3 months of initial injury) due to a fall on the outstretched arm, a direct repair of the ligament may be possible. If the ligament has pulled off the humerus, it may be reattached with sutures through holes drilled in the bone. Direct repair of the existing ligament is only performed when the ligament has pulled away from the humeral attachment. This is known as an MCL “avulsion” and is rare.
2) MCL Reconstruction:
If the ligament is damaged by constant overuse and is not strong enough to restore stability to the elbow joint if it is simply reattached or repaired, reconstruction of the MCL is recommended. The torn MCL must be replaced with a new ligament. Commonly, an accessory tendon from the forearm (called the Palmaris longus tendon) is used to reconstruct the MCL. This is known as an “autograft” because the graft was harvested from somewhere else in the body. The MCL can also be reconstructed with donor tendon called an “allograft.” The graft will be positioned over the MCL complex and secured to the humerus and ulna with anchors.
Ulnar Nerve decompression: During surgery the surgeon may find that the ulnar nerve (which travels along the inner side of the elbow and down to the hand) is compressed. The surgeon will carefully open the roof of the cubital tunnel at the site of the compression, creating more space for the ulnar nerve. The nerve is often moved out of the tunnel and repositioned along a new path to prevent it from being compressed in the future. If the nerve is compressed in multiple places, more than one section of the tunnel may require treatment.
Post Operative Rehabilitation:
Following Arthroscopic Debridement, gentle range of motion exercises will be started right away. Full motion is restored as the pain and swelling resolve. Elbow strengthening exercises are begun within the first few days to week after the procedure. A rehabilitation program is started and progressed, including a gradual throwing program. Full sports participation can be anticipated within one to three months.
The postoperative protocol is the same for both MCL Repairs and MCL Reconstructions, as shown below.
Note: These instructions are to serve as guidelines and are subject to Physician discretion. Actual progress may be faster or slower depending on the individual.
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