Hu Xu1, Chunli Zhang2, Qiang Zhang3, Tianshu Du1, Ming Ding1, Yingchun Wang1, Sai-Chuen Fu4, Chelsea Hopkins4, Shu-Hang Yung4. 1. Institution of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi'an, China. 2. Institution of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi'an, China. Electronic address: zhang2014chunli@163.com. 3. Institution of Orthopedics, The Third People's Hospital, Hefei, China. 4. Department of Orthopaedics and Traumatology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong SAR, China.
Abstract
PURPOSE: To unravel the standard position of anterior cruciate ligament (ACL) femoral origin and deduce practical arthroscopic localization and postsurgical evaluation method. METHODS: Two independent reviewers searched PubMed using the terms ACL, footprint, femur, etc. We included studies published since January 1, 2000, in which the results were measured by Bernard's quadrant method. This method consists of 4 distances, including total diameter of lateral condyle along Blumensaat's line (distance t), maximum intercondylar notch height (distance h), distance from center of footprint to proximal border (distance x), and distance from center of footprint to Blumensaat's line (distance y). The data of included studies were combined to calculate theoretical centers and standard area for both ACL as a whole bundle and as anteromedial (AM) and posterolateral (PL) bundles individually. Finally, we translated the combined data to arthroscopic localization and postsurgical evaluation. RESULTS: A total of 13 studies were included. The theoretical centers of ACL as a whole bundle is 28.4% ± 5.1% (x) of distance t and 35.7% ± 6.9% (y) of distance h, whereas AM bundle is 24.2% ± 4%, 21.6% ± 5.2% (x, y) and PL bundle is 32.8% ± 4.7%, 46.7% ± 4.9% (x, y), respectively. The standard area of ACL footprint is a circle with a center of 27.53%, 35.85% (x, y), and a radius of 4.58%, 9.2% (x, y), respectively. Translation of combined data shows that under arthroscopy, for single-bundle ACL reconstruction, the midpoint of distance from border of proximal to distal articular cartilage is the center of anatomic femoral socket. CONCLUSIONS: Combined data unravel the standard position of ACL femoral origin. It can be used by clinicians to localize anatomic tunnel both in surgery and postsurgical evaluation. For single-bundle ACL reconstruction, the midpoint of lateral femoral condyle corresponds to anatomic socket. LEVEL OF EVIDENCE: Level V, systematic review of anatomic studies.
PURPOSE: To unravel the standard position of anterior cruciate ligament (ACL) femoral origin and deduce practical arthroscopic localization and postsurgical evaluation method. METHODS: Two independent reviewers searched PubMed using the terms ACL, footprint, femur, etc. We included studies published since January 1, 2000, in which the results were measured by Bernard's quadrant method. This method consists of 4 distances, including total diameter of lateral condyle along Blumensaat's line (distance t), maximum intercondylar notch height (distance h), distance from center of footprint to proximal border (distance x), and distance from center of footprint to Blumensaat's line (distance y). The data of included studies were combined to calculate theoretical centers and standard area for both ACL as a whole bundle and as anteromedial (AM) and posterolateral (PL) bundles individually. Finally, we translated the combined data to arthroscopic localization and postsurgical evaluation. RESULTS: A total of 13 studies were included. The theoretical centers of ACL as a whole bundle is 28.4% ± 5.1% (x) of distance t and 35.7% ± 6.9% (y) of distance h, whereas AM bundle is 24.2% ± 4%, 21.6% ± 5.2% (x, y) and PL bundle is 32.8% ± 4.7%, 46.7% ± 4.9% (x, y), respectively. The standard area of ACL footprint is a circle with a center of 27.53%, 35.85% (x, y), and a radius of 4.58%, 9.2% (x, y), respectively. Translation of combined data shows that under arthroscopy, for single-bundle ACL reconstruction, the midpoint of distance from border of proximal to distal articular cartilage is the center of anatomic femoral socket. CONCLUSIONS: Combined data unravel the standard position of ACL femoral origin. It can be used by clinicians to localize anatomic tunnel both in surgery and postsurgical evaluation. For single-bundle ACL reconstruction, the midpoint of lateral femoral condyle corresponds to anatomic socket. LEVEL OF EVIDENCE: Level V, systematic review of anatomic studies.