Graft Harvesting and Preparation

The semitendinosus and gracilis tendons are harvested in the usual fashion. Each tendon must be at least 20 cm long because, when folded, a 10-cm-long final graft construction is desired. The free grafts are taken to the Grafix Prep Table for preparation. Both tendons are measured and cut to the desired length (20 to 22 cm), and then muscle is removed with an osteotome or a periosteal elevator. Once cut and cleaned, each end of the individual graft tendon is whipstitched approximately 35 to 40 mm from the end with a #2 nonabsorbable suture. If the surgeon plans to use the SE Graft Tensioner for tibial fixation, the graft’s bundles must be identified. This is easily accomplished by applying one knot to the semitendinosus sutures and two to the gracilis or by using a surgical marker pen.

Using the graft sizing block, the entire graft bundle diameter is measured. It is important to take measurements of the femoral and tibial ends (Fig. 35-3); these diameters will determine the proper sizes of the cross-pin graft harness and tunnel. The graft harness size (8 or 9 mm) should always be selected based on the diameter of the femoral end of the graft.

Fig. 35-3 Measure the diameter of the femoral and tibial ends.

Not infrequently, the entire graft size is not uniform; usually the tibial end increases 1 mm because of the morphology of the tendon and the placed sutures. If this is the case, the cross-pin graft harness must match the femoral graft diameter. For tunnel creation, two different drill bits will be used, with the smaller drill bit for the femoral tunnel and the larger for the tibial tunnel.

To load the graft strands into the graft harness (Fig. 35-4), place the graft harness onto the harness holder accessory and pass the graft strands individually through the continuous suture loop on the graft harness.

Fig. 35-4 Graft mounted in the harness.

Notchplasty and ACL Stump Removal

The ACL stump is removed with the shaver. The notchplasty is large enough to accommodate the graft; this is usually possible by just removing the soft tissues on the lateral wall of the notch with the shaver or a curette. Sometimes in chronic cases in which stenotic bone is found, notchplasty will include some bone resection.

Tibial and Femoral Tunnel Creation

The Pinn-ACL tibial guide, set at 55 degrees, is inserted into the knee through the medial working portal. The tip of the guide is placed in the posterior aspect of the tibial ACL stump following an imaginary line along the posterior border of the lateral meniscus anterior horn and centered in the midline of the joint. The guide pin should enter the tibia 5 cm below the medial joint line and 2 to 3 cm medial to the anterior tibial tuberosity in a position adjacent to the medial collateral ligament; this alignment will create a tibial tunnel that allows a more oblique femoral tunnel, usually around the 65-degree angle.^15,16 The guide pin is advanced into the tibia, and arthroscopic visualization is used to check the correct position of the guide pin in the joint. An AccuDrill reamer corresponding to the graft’s tibial size is used to create the tibial tunnel.