**7.2 Drilling**

During drilling, the knee must be bent at least at 110 degree of flexion in order to avoid blowing up the posterior wall of the lateral femoral condyle (Fig. 10). The more the knee is

Contemporary Anterior Cruciate Ligament Reconstruction 209

Anatomic ACL reconstruction is defined as the functional restoration of the ACL to its native dimensions, collagen orientation, and insertion sites (Van Eck et al., 2010). The concept and development of double-bundle ACL reconstruction comes from the rediscovery of the ACL bundles anatomy and biomechanics of ACL reconstruction. Several studies have shown that rotational control of the tibia as well as anterior tibial translation were much improved when the PLB was reconstructed in addition to the AMB (Colombet et al., 2007; Kanaya et al., 2009; Markolf et al., 2009; Sbihi et al., 2004; Yagi et al., 2002; Zaffagnini et al.,

Already in his original transtibial technique, T Rosenberg was mentioning the possibility to reconstruct 2 bundles, if the femoral footprint size was big enough, by drilling 2 sockets in the femur and one tunnel in the tibia. This idea was further developed in Japan (Hara et al., 2000; Hamada et al., 2001; Mae et al., 2001;Munetta et al., 1999), then in France (Franceschi et al, 2002; Bellier et al., 2004 ) and finally in the USA. While few authors persisted in the use of transtibial technique (Yasuda et al., 2004), it appeared rapidly to most surgeons that double bundle ACL reconstruction which necessitates drilling 2 femoral sockets and 2 tibial tunnels could be only performed either with transportal technique or two-incision

**8.1** Following is a brief summary of the principles of anatomic double-bundle ACL reconstruction technique. We will describe transportal technique with four tunnels, which is the most widely used. Few surgeons are using alternative techniques like two-incision- (Aglietti et al., 2005) or modified transtibial technique (Yasuda et al., 2004). Most of the authors use autogenous hamstring tendons. Usually the AMB is reconstructed with a double-stranded semitendinosus tendon, while the gracilis is used for the PLB. According to their size or length, tendons can be doubled, tripled or even quadruple-stranded. Allografts are used mostly in the USA. In Western patients, with autogenous hamstrings, the average AMB diameter is 7mm (6-9mm) and PLB 6mm (5-7mm). Most of the authors use Endobutton® CL for the femoral fixation. Others are using interference screws. On the tibial side, various fixation methods have be described: interference screws, plate and screw, screw post and washer. As femoral tunnels are drilled independently one may start either

The femoral footprint is visualized through an AM portal and carefully identified according to the landmarks previously described (Cha et al., 2005). Identifying the intercondylar ridge is a key issue and fluoroscopy may help. Through an accessory AM portal two sockets are drilled through the center of each bundle attachment with the knee bent at least at 110° of flexion (Basdekis et al., 2008; Basdekis et al., 2009; Hoshino et al., 2009). Specific instruments allow proper positioning of the tunnels, keeping a 2-3 mm bone bridge (Fig. 11) between them in order to insure independent fixation of each bundle (Bellier et al., 2004; Christel et

**8. Development of anatomic double-bundle ACL reconstruction** 

technique

2008; Zantop et al., 2007).

by drilling tibial- or femoral tunnels.

**8.1.1 Femoral tunnels** 

technique.

However, Chhabra et al (Chhabra et al., 2006) comparing transtibial femoral tunnel expansion vs AM drilling found significantly less enlargement with the transportal

bent the longer is the femoral tunnel (Basdekis et al., 2008). It might be necessary to resect part of the fat pad in order to obtain an appropriate vision of the lateral wall of the notch. Keeping the scope through the AL portal provides a tangential view of the lateral wall of the notch and the ACL footprint. So, in order to insure a good visualization of the footprint it is better to view the notch from the medial side of the knee. Placing the scope through a proximal AM portal and the instruments through an accessory AM portal is also called three-portal technique (Cohen & Fu, 2007) as it combines one AL portal with 2 AM portals. Watching the lateral wall of the intercondylar notch from medial provides a full view of the ACL foot print from the anterior cartilage margin to the posterolateral outlet and allows precise visualization of the lateral intercondylar ridge.

Fig. 10. Drilling the femoral tunnel transportal. The knee is bent at least at 110 degree of flexion. The scope is through the PAM portal and the drill through the DAM portal (Right knee).

### **7.3 Transportal drilling limitations**


bent the longer is the femoral tunnel (Basdekis et al., 2008). It might be necessary to resect part of the fat pad in order to obtain an appropriate vision of the lateral wall of the notch. Keeping the scope through the AL portal provides a tangential view of the lateral wall of the notch and the ACL footprint. So, in order to insure a good visualization of the footprint it is better to view the notch from the medial side of the knee. Placing the scope through a proximal AM portal and the instruments through an accessory AM portal is also called three-portal technique (Cohen & Fu, 2007) as it combines one AL portal with 2 AM portals. Watching the lateral wall of the intercondylar notch from medial provides a full view of the ACL foot print from the anterior cartilage margin to the posterolateral outlet and allows

Fig. 10. Drilling the femoral tunnel transportal. The knee is bent at least at 110 degree of flexion. The scope is through the PAM portal and the drill through the DAM portal (Right




precise visualization of the lateral intercondylar ridge.

knee).

notch

**7.3 Transportal drilling limitations** 

transtibial insertion only

However, Chhabra et al (Chhabra et al., 2006) comparing transtibial femoral tunnel expansion vs AM drilling found significantly less enlargement with the transportal technique
