Anterior cruciate ligament (ACL) reconstruction with quadriceps tendon autograft and press-fit fixation using an anteromedial portal technique

Abstract

Background: This article describes an arthroscopic anterior cruciate ligament (ACL) reconstruction technique with a quadriceps tendon autograft using an anteromedial portal technique.

Methods: A 5 cm quadriceps tendon graft is harvested with an adjacent 2 cm bone block. The femoral tunnel is created through a low anteromedial portal in its anatomical position. The tibial tunnel is created with a hollow burr, thus acquiring a free cylindrical bone block. The graft is then passed through the tibial tunnel and the bone block, customized at its tip, is tapped into the femoral tunnel through the anteromedial portal to provide press-fit fixation. The graft is tensioned distally and sutures are tied over a bone bridge at the distal end of the tibial tunnel. From the cylindrical bone block harvested from the tibia the proximal end is customized and gently tapped next to the graft tissue into the tibial tunnel to assure press fitting of the graft in the tibial tunnel. The distal part of the tibial tunnel is filled up with the remaining bone.All patients were observed in a prospective fashion with subjective and objective evaluation after 6 weeks, 6 and 12 months.

Results: Thirty patients have been evaluated at a 12 months follow-up. The technique achieved in 96.7% normal or nearly normal results for the objective IKDC. The mean subjective IKDC score was 86.1 ± 15.8. In 96.7% the Tegner score was the same as before injury or decreased one category. A negative or 1+ Lachman test was achieved in all cases. Pivot-shift test was negative or (+) glide in 86.7%. The mean side-to-side difference elevated by instrumental laxity measurement was 1.6 ± 1.1 mm. Full ROM has been achieved in 92.3%. The mean single one-leg-hop index was 91.9 ± 8.0 at the follow-up.

Conclusions: Potential advantages include minimum bone loss specifically on the femoral side and graft fixation without implants.

Figure 1

Harvesting the quadriceps tendon graft. a. The proximal end of graft whipstitched using # 2 polyester suture. b. The sutured end of the graft was threaded through a hollow burr, which was attached to an oscillating compression air drill (Richard Wolf, Knittlingen, Germany). c. The cutting edge of a 9.4 mm hollow burr for graft harvesting. Two thirds of the circumference of this specific hollow burr had sharp teeth, while the other 1/3 was blunt. Using the hollow burr with in inner diameter of 9.4 mm, a cylindrical bone cylinder of 20 mm length could be harvested from the proximal aspect of the patella.

Figure 2

The cylindrical 20 mm bone block at the end of the graft had a diameter of 9.4 mm and a graft sizer was used to ensure that it could be completely passed through a 9.4 mm template.b. For later easier graft placement in the femoral tunnel, the apex of the bone block was prepareted in a fashion, that its distal 1 cm just fitted into a 9.0 mm template.

Figure 3

Complete graft with a 50 mm strip of quadriceps tendon and a 20 mm cylindrical bone plug.

Figure 4

The right knee was flexed to 120. After a 2.4 mm guide wire was introduced into the lateral femoral condyle through the anteromedial portal, an 8.0 mm cannulated reamer was used to create a socket into the femur of 20 mm in length.

Figure 5

With the knee flexed to 120°, the bone cylinder was pulled into the femoral tunnel. Then an impactor was used to tap the bone cylinder into the femoral tunnel until the bone lock is flush with the femoral cortex.

Figure 6

The bone block of the graft was flush with the femoral cortex with press-fit fixation. Tibially, a split bone wedge harvested from the tibia the graft was compressed against the bone tunnel wall close to the joint line, furthermore the graft was secured with sutures tied over a bone bridge. The remaining part of the harvested bone plug was stuffed into the tibial tunnel like a cork to close the bone tunnel distally.

Figure 7

CT scan of the right knee 6 weeks postoperatively.