The patient is placed in the supine position with the arm laid across the body or on an arm board. Before beginning, an examination under anesthesia is performed with special attention paid to the posterolateral rotatory drawer test and the lateral pivot-shift test. If desired, a nonsterile tourniquet can be placed high on the arm out of the surgical field.

A 7-cm incision is made from just proximal to the lateral epicondyle toward the crista supinatorius on the ulna. Once through skin and subcutaneous tissue, the interval (Kocher's interval) between the anconeus and the extensor carpi ulnaris is identified (Fig 1). The fascia is sharply incised, and blunt dissection is carried out down to the capsule. It is important that the lateral capsule be identified and protected throughout the case because the ligament will ultimately be reconstructed in an extra-articular position. The capsule is incised in line with the LUCL, just anterior to the posterior margin of the extensor tendon so that there is thick enough tissue to suture during imbrication and closure.

Attention is turned to the supinator crest, and subperiosteal dissection is performed just posterior and proximal to its apex. The ulnar tunnel is created by converging the bases of two 3.2-mm-diameter sockets (Fig 2A). The first begins immediately posterior to the supinator crest and the second is located proximal and posterior to a bony bridge of at least 1.25 cm between the holes. Once both sockets are drilled, their bases can be connected and cleared of bone debris using a Bankart awl (Kirwan, Marshfield, MA) with a similar radius of curvature as the curved needle of the passing suture. A looped suture is passed through the tunnel using a curved needle. It is tagged and set aside for later graft passage.

Once the ulnar tunnel is created, attention is turned to creating the humeral socket. An appropriately positioned humeral attachment site should provide an isometric reconstruction that maintains the same tension throughout the flexion-extension arc. This point is typically at the geometric center of a circle superimposed on the capitellar articular margin (Fig 2B). The isometry of this point can be confirmed by pulling the free ends of the passing suture from the ulnar tunnel to this location using a hemostat once a small starting indentation has been created with the 3.2-mm drill (Fig 2C). The suture should demonstrate even tension and isometry as the elbow is flexed and extended. With a 3.2-mm drill, the humeral socket is drilled toward, but not through, the posterior cortex to a depth of 15 mm. The center of this socket is placed approximately 1 mm proximal and 1 mm posterior to the previously identified isometric point. The center of the socket is moved just proximal and posterior because once tensioned, the graft will drape along the anteroinferior rim of the socket, which brings it back to the isometric point. A second socket is drilled toward, but not through, the anterior cortex.

A 2.0-mm drill is used to create 2 holes proximally on either side of the supracondylar ridge, one posteriorly and the other anteriorly. These holes should be at least 10 mm apart to provide a strong bony bridge over which sutures can be tied at the end of the case. A looped passing suture is passed through each tunnel and tagged for later graft passage.

Although autograft (palmaris or split hamstring tendon) can be used, we prefer to use the allograft plantaris tendon to minimize the surgical morbidity to the patient. If semitendinosus or peroneus longus allograft tendons are used, they are split to reduce bulk. In one end of the graft, a running locked suture (No. 2-0 Fiberwire; Arthrex, Naples, FL) is placed and the remaining end is initially left free. Before graft passage, imbricating “vest-over-pants” capsular sutures are placed so that the capsulotomy can be closed at a later stage (Fig 2D). These are tagged but not tied until the graft has been passed.

Using the passing suture, the graft is passed through the ulnar tunnel from proximal to distal (Fig 3A). The sutured end is then docked into the posterior humeral socket using the posterior passing suture that was previously placed. The free end is laid across the aperture of the humeral socket and tensioned, whereas the elbow is flexed and extended. The tendon is marked a few millimeters proximal to the aperture, and a second running, locking stich is applied from this mark traveling 10 mm away from the free end (Fig 3B). The excess graft is excised and the free end is docked into the socket using the anterior passing suture (Fig 3C). Once again, the graft is tensioned, whereas the elbow is taken through a flexion-extension arc. Before securing the graft, the capsule is closed using the previously placed capsular sutures to ensure that the graft remains extra-articular. The graft is now secured by tying the sutures over the bone bridge. Care is taken to ensure that the knot is placed on the anterior surface of the humerus to avoid irritation under the thin posterior skin (Fig 3D). The wound is then closed in layers.

Although we are not certain as to the optimum postoperative management, we immobilize the arm in a long-arm cast for 3 weeks. A removable thermoplastic splint is applied for 3 more weeks. It is removed 4 times per day to do overhead range of motion (ROM) exercises in the supine position. Anytime the elbow is moved away from the body, the weight of the forearm is supported by the other hand to prevent inadvertent varus torque during these activities. ROM is progressed as able with a goal of achieving full ROM by three months post-operative. At 3 months, focus is shifted toward strengthening the elbow flexors, extensors, pronators, and supinators. Unrestricted activity and return to sport are generally allowed 6 months after surgery.