A previously healthy 12-year-old male patient was presented to our clinic with right knee pain and functional instability, 1.5 years after a football injury. On physical examination, the knee was unstable with a highly positive Lachman test (Figure 1) and anterior drawer test (Figure 2), there was a mild effusion, collateral ligaments appeared stable, and meniscus signs were negative. MRI revealed a complete tear of the ACL. In addition, an osteochondral lesion of the lateral femoral condyle with a diameter of 1.5 cm was seen. He had been treated nonoperatively with physiotherapy in another facility and was referred due to ongoing pain and giving-way episodes. For his age, the patient was very early in his development (Tanner stage 1) with wide open physes of femur and tibia. After discussing several options with the patient and his parents, we decided to proceed with an all-epiphyseal ACL reconstruction using a quadricep tendon autograft.
Under general anesthesia and nerve block, the patient was positioned in supine position on the normal table (Figure 3). A perioperative single-shot antibiotic coverage was given, and a tourniquet was applied.
First, a 5 cm x 10 mm x 5 mm quadricep tendon autograft was harvested through a minimally invasive technique (Figure 4) and prepared for an all-inside ACL reconstruction. Here, 15 mm of both ends of the graft was augmented with a fiber loop with fiber tag (FiberLoop w FiberTag Braided Polyblend Blue Suture Loop 20") (Arthrex) and connected to an ACL tight rope (ACL TIGHTROPE) (Arthrex) .
Then arthroscopic examination of the knee was performed, which revealed a total tear of the ACL. The remnants were debrided, and the femoral and tibial footprints were identified (Figure 5), leaving some tibial fibers in place. Both menisci appeared normal, and the cartilage was unremarkable. Even on the lateral femoral condyle, which demonstrated an osteochondral lesion on MRI, the cartilage appeared stable and did not require any further surgical attention.
Under fluoroscopy (Figure 6) in true lateral position as well as under direct arthroscopic vision, a guidewire was placed into the exact femoral footprint of the ACL from outside-in. This was over drilled with a 7 mm FlipCutter (FlipCutter II S. A.-N.-1.-7.) (Arthrex) to create the final 1.5 to 2 cm long femoral tunnel. Guiding sutures were pulled through the femoral condyle for later graft placement. During the entire process, it was made sure that the drilling was done strictly epiphyseal.
On the tibial side, a guidewire was inserted from the anteriomedial aspect of the proximal tibia into the posterior part of the tibial ACL footprint. It was over drilled with a 6 mm FlipCutter (FlipCutter II S. A.-N.-1.-6.) (Arthrex) in retrograde fashion to create a 1.5 cm tibial tunnel. The drilling again was done under fluroscopic control for a strict epiphyseal position. Guiding sutures were placed in the tibial tunnel and consequently retrieved together with the femoral sutures through the anteriomedial arthroscopic portal. Then, the femoral end of the graft was inserted through the arthroscopic portal, the button flipped on the outside of the lateral femoral condyle, and the graft pulled into the femoral tunnel. The tibial end of the graft was inserted in the similar way, followed by 10 ranges of motion cycles of the knee. Finally, the graft was tensioned in about 20 degrees of flexion. A distal ABS button (TightRope ABS (Attachable Button System)) (Arthrex) was inserted under direct vision to ensure its direct sit on the bone (Figure 7). A final arthroscopic check of the graft and washout of all debris was performed, wounds were closed, and a brace was put on the leg.
The postoperative protocol included early mobilization with weightbearing as tolerated. The child was allowed to remove or wear the brace as wished. Closed chain exercises were initiated early postoperative with special precautions for the weakened quadricep tendon. Physiotherapy continued routinely for 6 weeks postoperatively followed by a guided exercise program. A return to high pivoting activities and competitive sports was only allowed after 9 months.