Ulnar Collateral Ligament (UCL) reconstruction, commonly known as Tommy John surgery, is a procedure designed to restore stability to the inner elbow. This ligament connects the humerus (upper arm bone) to the ulna (forearm bone). The UCL is frequently torn due to the repetitive, high-velocity stress of overhead throwing motions, common in baseball pitchers and other athletes. The surgery replaces the damaged native tissue with a new tendon graft, effectively creating a new ligament to stabilize the joint. The success of this reconstruction allows many athletes to return to their previous level of competition.
Preparing for UCL Reconstruction
The procedure begins with the patient under general anesthesia, positioned on their back with the arm extended. A tourniquet is applied to the upper arm to manage blood flow, and the area is prepped for sterility. The surgeon then makes an incision, typically three to four inches long, along the inside of the elbow.
The soft tissues, including the skin and muscle layers, are carefully separated to expose the damaged UCL beneath. The surgeon identifies and protects the ulnar nerve, which runs close to the surgical site, sometimes rerouting it if it is unstable or damaged.
Before replacement begins, the necessary tendon graft must be acquired and prepared. The most common source is the Palmaris Longus tendon from the forearm, harvested through small, separate incisions. Other potential sources for this autograft include the hamstring, toe extensors, or a tendon from the knee. Once harvested, the tendon is prepared to be the new ligament.
The Reconstruction Process
The actual reconstruction begins with the creation of precise tunnels drilled into the bones. These tunnels are placed at the anatomical attachment sites of the original UCL, spanning the inner bump of the humerus and the upper part of the ulna. The number and configuration of these bony tunnels vary based on the specific technique the surgeon uses.
In the ulna, two tunnels are often drilled to create a loop for the new graft to pass through. The humerus typically receives a central tunnel, sometimes with two smaller holes branching out, or a single tunnel for fixation. These tunnels are placed to ensure the new ligament will have the correct length and tension across the joint. Strong sutures are then threaded through the tunnels to act as guides for pulling the tendon graft into position.
The prepared tendon is looped through the ulnar tunnels and stretched across the elbow joint. Two popular methods for securing the graft are the docking technique and the figure-eight technique, both of which use the tunnels to anchor the replacement tissue. In the docking technique, the ends of the graft are pulled into the humeral tunnel and secured under tension with sutures tied over a bone bridge or with screws.
The figure-eight technique involves weaving the tendon through the tunnels in a continuous, looping pattern and then suturing the ends of the graft back onto the main tendon body. The surgeon adjusts the tension on the graft while moving the elbow through its range of motion. This step ensures the new ligament provides optimal joint stability without restricting movement. Once the tension is correct, the graft is permanently secured within the bone tunnels using high-strength sutures, anchors, or screws.
Immediate Post-Surgical Stabilization
After the new ligament is secured and tested for stability, the surgical site is closed. The layers of muscle and soft tissue are brought back together and sutured. The outer incision is then closed with sutures or staples.
A sterile dressing and a bulky bandage are applied to protect the incision and manage initial swelling. Immediately following the operation, the patient’s arm is placed into a rigid, protective splint or cast. This splint typically holds the elbow at a fixed angle for the first one to two weeks. This immediate immobilization shields the reconstructed UCL from movement or strain that could compromise the graft before early healing begins.