The femoral posterior fan-like extension of the ACL insertion increases the failure load

• Published in: Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA sports traumatology, arthroscopy : official journal of the ESSKA, 2020-04, Vol.28 (4), p.1113-1118
• Main Authors: Sabzevari, Soheil, Shaikh, Humza, Marshall, Brandon, Zhu, Junjun, Linde, Monica A., Smolinski, Patrick, Fu, Freddie H.
• Format: Article
• Language: English
• Subjects: Anterior cruciate ligament; Failure load; Femur; Flexing; Footprints; Insertion; Knee; Ligaments; Medicine; Medicine & Public Health; Orthopedics; Preservation
• ISSN: 0942-2056; 1433-7347
• DOI: 10.1007/s00167-019-05753-3

Purpose To examine the role of the posterior fan-like extension of the ACL’s femoral footprint on the ACL failure load. Methods Sixteen ( n  = 16) fresh frozen, mature porcine knees were used in this study and randomized into two groups ( n  = 8): intact femoral ACL insertion (ACL intact group) and cut posterior fan-like extension of the ACL (ACL cut group). In the ACL cut group, flexing the knees to 90°, created a folded border between the posterior fan-like extension and the midsubstance insertion of the femoral ACL footprint and the posterior fan-like extension was dissected and both areas were measured. Specimens were placed in a testing machine at 30° of flexion and subjected to anterior tibial loading (60 mm/min) until ACL failure. Results The intact ACL group had a femoral insertion area of 182.1 ± 17.1 mm 2 . In the ACL cut group, the midsubstance insertion area was 113.3 ± 16.6 mm 2 , and the cut posterior fan-like extension portion area was 67.1 ± 8.3 mm 2 . The failure load of the ACL intact group was 3599 ± 457 N and was significantly higher ( p