Anterior Cruciate Ligament Reconstruction with Quadriceps Tendon Autograft

Abstract

A graft from the central quadriceps tendon for ACL reconstruction is easily obtained, causes minimal morbidity and has a track record of excellent results. Graft sizes of 10-12 mm wide X 7-8 mm thick and up to 120 mm of length are possible. A bone plug is optional. The popularity of the quadriceps tendon graft is increasing.

Keywords

ACL, loose plug, Quadriceps tendon graft

Keywords

ACL, loose plug, Quadriceps tendon graft

Introduction

The central quadriceps tendon is an excellent graft source for both primary and revision anterior cruciate ligament reconstruction (ACLR). A graft 10–12 mm wide, 7–8 mm thick, and up to 120 mm in length can be harvested in most adults. The graft can include a bone plug from the proximal patella or can be harvested as a soft tissue graft only. Fulkerson and Langeland, Staubli, and Blauth have published techniques for quadriceps tendon graft harvest.

Technique

The leg is placed in an arthroscopic leg holder, with the hip flexed moderately to allow hyperflexion of the knee. A tourniquet is routinely used. Exposure of the distal quadriceps tendon is made by a sagittal incision at the superior margin of the patella of about 2.5–3 cm in length ( Fig. 34.1 ). The skin in this area is quite mobile. After the subcutaneous fat is cleaned away, the tendon is clearly exposed.

The freehand technique of graft harvest requires incising the tendon with a #10 knife blade straight down to the superior pole of the patella to a depth of 7–8 mm at the edge of the vastus medialis obliquus (VMO). A second incision is made approximately 10 mm lateral to the first, parallel and straight down to the patella. When harvesting a soft tissue graft, the tendon is dissected from the patella with a #15 knife blade and advanced proximally. The first 25 mm of graft is sized to 9 mm. Two strong whipstitches are placed in the end of this graft. If the graft is to be harvested with a bone plug, a 9 × 9 × 25 mm ³trapezoidal piece of the patella with the tendon attached is cut with a saw.

As the tendon is dissected proximally, a small fat pad is encountered at the superior tip of the patella. The tendon is incised proximally, leaving a 1-mm layer of suprapatellar pouch for a distance of 3–4 cm. Surgical scissors are used to further longitudinally strip the remaining tendon up to a length of about 85–95 mm. The tendon is divided proximally with the scissors, and the defect in the quadriceps tendon is closed side to side with absorbable suture. Another method of quadriceps tendon graft harvest uses a commercially available harvest set. The cutting instrument is a disposable-tip knife with two parallel blades 10 mm apart and 7 mm deep. It is used to make the initial parallel cuts in the tendon. A second instrument pulls the graft through an opening, stripping it proximally to a distance of 85–95 mm where it is amputated. The main body of the graft is sized to 10 or 11 mm. A graft is thus produced with an overall length of 85–95 mm, the first 30 mm being 9 mm in size for the femoral socket. The proximal graft is then split between the interval between the vastus intermedius and rectus femoris. A layer of fat between these two tendons is present and facilitates this dissection. A whipstitch is put in each limb of the proximal end of the graft ( Fig. 34.2 ).

For a double-bundle ACLR, the dissection between the vastus intermedius and rectus femoris can be carried all the way down to the end of the tendon, creating two separate bundles. The rectus femoris part of the tendon is usually thicker and makes an excellent choice for an anterior medial bundle graft. The vastus intermedius is usually smaller and can be used for the posterolateral bundle.

For single-bundle reconstruction and interference screw fixation, the tibial tunnel is reamed at an approximate 50-degree angle about 2–2.5 fingerbreadths medial to the patellar tendon into the middle to anterior part of the tibial footprint of the old ACL. A low anterior medial accessory portal is used to locate the femoral tunnel in the correct anatomical position. It is then reamed a depth of 30 mm, with a 9-mm reamer at a point, down the femoral side wall between the insertions of the anteromedial and posterolateral bundle.

After completing the tunnels, the distal end of the graft, sized to 9 mm, is pulled through the tibial tunnel and into the femoral socket with a pull-through suture ( Fig. 34.3 ). Prior to insertion of the graft, a flexible guide pin is placed between the two split tails of the graft for the insertion of a tibial interference screw, and a second guide pin is placed through the low anteromedial portal into the femoral tunnel. Fixation of the graft is accomplished with a 7 × 25 mm ²absorbable screw on the femoral side first. The tibial side is then secured with an absorbable screw 1 mm smaller than the diameter of the tibial tunnel. The whipstitches in the two limbs of the tibial side of the graft are then passed through the periosteum at the edge of the tibial tunnel and tied together for secondary backup fixation. The knee is carried through a range of motion to make sure that impingement of the graft is not present, and the graft is checked for appropriate tension. The incisions are closed with subcuticular absorbable sutures and Steri-Strips, and the patient is placed in a knee immobilizer for 48 hours.