1. Effect of Tibial Drill Angles on Bone Tunnel Aperture During Anterior Cruciate Ligament Reconstruction by Sebastian Kopf, Daniel E. Martin, Scott Tashman, and Freddie H. Fu J Bone Joint Surg Am Volume 92(4):871-881 April 1, 2010 ©2010 by The Journal of Bone and Joint Surgery, Inc.

2. Superior view on the tibial plateau, showing the proximity of the anterior cruciate ligament insertion site with its two bundles, the anteromedial (AM) and posterolateral (PL) bundles, to the surrounding soft-tissue structures. Sebastian Kopf et al. J Bone Joint Surg Am 2010;92:871- 881 ©2010 by The Journal of Bone and Joint Surgery, Inc.

3. The tibia with the tibial drill-guide set to an angle (α) of 45°. Sebastian Kopf et al. J Bone Joint Surg Am 2010;92:871- 881 ©2010 by The Journal of Bone and Joint Surgery, Inc.

4. Tibia (saw-bone model) with a drill guide showing the transverse angle (β). Sebastian Kopf et al. J Bone Joint Surg Am 2010;92:871- 881 ©2010 by The Journal of Bone and Joint Surgery, Inc.

5. The tibial bone tunnel in the sagittal plane of a computed tomography scan showing the diameter of the bone tunnel (equal to the drill-bit diameter) (d), the major axis of the ellipse (hypotenuse) (h), and the angle at which the bone tunnel intersects the c... Sebastian Kopf et al. J Bone Joint Surg Am 2010;92:871- 881 ©2010 by The Journal of Bone and Joint Surgery, Inc.

6. a: Tibial tunnel aperture (blue dotted line) precisely oriented with the native anterior cruciate ligament (ACL) insertion (yellow line). b: Tibial tunnel aperture malrotated by 45° relative to the native tibial anterior cruciate ligament insertion in the t... Sebastian Kopf et al. J Bone Joint Surg Am 2010;92:871- 881 ©2010 by The Journal of Bone and Joint Surgery, Inc.

7. Tibial bone-tunnel aperture length (in millimeters) is dependent on the drill-guide angle and the drill-bit diameter (7, 9, and 11 mm). Sebastian Kopf et al. J Bone Joint Surg Am 2010;92:871- 881 ©2010 by The Journal of Bone and Joint Surgery, Inc.

8. Three-dimensional model of a human tibia demonstrating the effect of different drill-guide angles on the tibial tunnel aperture size and surrounding osseous structures. Sebastian Kopf et al. J Bone Joint Surg Am 2010;92:871- 881 ©2010 by The Journal of Bone and Joint Surgery, Inc.

9. Effect of changed transverse drill angle on the missed area of the tibial tunnel aperture orientation relative to the native tibial insertion of the anterior cruciate ligament (with use of a 9- mm drill-bit diameter at a 45° drill-guide angle). Sebastian Kopf et al. J Bone Joint Surg Am 2010;92:871- 881 ©2010 by The Journal of Bone and Joint Surgery, Inc.