Fig. 21.1
Positioning. The distal thigh is kept horizontal using a leg holder with the calf hung down by gravity
Fig. 21.2
Three arthroscopic portals. In addition to the routine anterolateral (AL) and anteromedial (AM) portals, the far anteromedial (FAM) portal which is 2–2.5 cm posterior to the anteromedial portal and just above the medial meniscus is created
The fibrous tissues including ACL stump on superior-posterior half of the lateral wall of the intercondylar notch is thoroughly removed using a radiofrequency device through the FAM portal while viewing via the AM portal. Mechanical shavers may not be utilized in order to preserve subtle undulation of the bony surface around the attachment area. After cleaning up, the crescent-shaped attachment area is clearly delineated by the resident’s ridge, anteriorly; proximal cartilage margin, superiorly; and posterior cartilage margin, posteriorly [1, 2, 9] (Fig. 21.3).
Fig. 21.3
Visualization of the ACL femoral attachment area. (a) The femoral attachment area covered with fibrous tissues viewed through the anteromedial portal. (b) The femoral attachment area with fibrous tissues thoroughly removed. The area is delineated by the resident’s ridge, proximal cartilage margin, and posterior cartilage margin
21.3 Creation of Two Femoral Tunnels for Hamstring Tendon Graft
The outside-in technique is suitable for cortical fixation, because the buttons could sit on the harder distal femoral cortex and because the tunnels are longer.
After exposure of the ACL femoral attachment area, the area is transversely divided into two portions: upper proximal portion for the anteromedial (AM) graft and lower posterior portion for the posterolateral (PL) graft. The centers of the two parts are marked with an awl (Fig. 21.4a). With the anterolateral entry femoral guide (Smith&Nephew # 6901189, or 7210984) through the AL portal, two guide pins are drilled from the lateral cortex to the marked centers through small skin incisions of 1 cm in length.
Fig. 21.4
Creation of two femoral tunnel in outside-in fashion. (a) Two guide pins are drilled into the center of anterior and posterior halves of the ACL attachment area from the lateral femoral cortex with the anterolateral entry femoral guide (Smith & Nephew # 6901189, or 7210984) via the anterolateral portal. (b) Created two tunnel apertures inside the femoral attachment area
21.4 Femoral Tunnel Creation for 10-mm Wide Bone-Patellar Tendon-Bone Graft
21.4.1 Rectangular Tunnel (KS)
This approach is especially recommended for the knee with passive flexion of less than 140°to avoid blowout of the tunnel. Viewing the ACL femoral attachment area via the AM portal, two points are marked with a 5-mm distance in the center of the attachment area along its long axis to the resident’s ridge using RF device or a micro-fracture awl. A central guide pin is drilled through a small lateral femoral incision into the center of the area from the lateral femoral cortex with the antero-lateral entry femoral guide (Smith&Nephew # 6901189, or 7210984) via the AL portal (Fig. 21.5). A 11-mm skin protection cannula is installed over the guide pin via 2-cm lateral femoral incision (Fig. 21.6a). With the aid of a 10-mm in-line offset drill guide, two guide pins are drilled parallel to the central pin along the long axis of the attachment area or the resident’s ridge that forms an angle of 30° to the femoral axis (Fig. 21.6b). After the central pin is removed, two guide pins are over-drilled with 5-mm drill-bit. With the dilator of 5 × 10 mm (Smith&Nehew, # E0014050-2) from the lateral femoral cortex, the two drill holes are dilated into one rectangular tunnel in outside-in fashion [4, 5] (Fig. 21.7).
