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. 2015 Nov;23(11):3136-42.
doi: 10.1007/s00167-014-3058-6. Epub 2014 May 20.

Flat midsubstance of the anterior cruciate ligament with tibial "C"-shaped insertion site

Rainer Siebold  1   2 , Peter Schuhmacher  3 , Francis Fernandez  3 , Robert Śmigielski  4 , Christian Fink  5 , Axel Brehmer  6 , Joachim Kirsch  7
Affiliations

Flat midsubstance of the anterior cruciate ligament with tibial "C"-shaped insertion site

Rainer Siebold et al. Knee Surg Sports Traumatol Arthrosc. 2015 Nov.

Erratum in

Abstract

Purpose: This anatomical cadaver study was performed to investigate the flat appearance of the midsubstance shape of the anterior cruciate ligament (ACL) and its tibial "C"-shaped insertion site.

Methods: The ACL midsubstance and the tibial ACL insertion were dissected in 20 cadaveric knees (n = 6 fresh frozen and n = 14 paraffined). Magnifying spectacles were used for all dissections. Morphometric measurements were performed using callipers and on digital photographs.

Results: In all specimens, the midsubstance of the ACL was flat with a mean width of 9.9 mm, thickness of 3.9 mm and cross-sectional area of 38.7 mm(2). The "direct" "C"-shaped tibial insertion runs from along the medial tibial spine to the anterior aspect of the lateral meniscus. The mean width (length) of the "C" was 12.6 mm, its thickness 3.3 mm and area 31.4 mm(2). The centre of the "C" was the bony insertion of the anterior root of the lateral meniscus overlayed by fat and crossed by the ACL. No posterolateral (PL) inserting ACL fibres were found. Together with the larger "indirect" part (area 79.6 mm(2)), the "direct" one formed a "duck-foot"-shaped footprint.

Conclusion: The tibial ACL midsubstance and tibial "C"-shaped insertion are flat and are resembling a "ribbon". The centre of the "C" is the bony insertion of the anterior root of the lateral meniscus. There are no central or PL inserting ACL fibres. Anatomical ACL reconstruction may therefore require a flat graft and a "C"-shaped tibial footprint reconstruction with an anteromedial bone tunnel for single bundle and an additional posteromedial bone tunnel for double bundle.

Keywords: ACL; Flat; Midsubstance; Ribbon; Tibial insertion; “C”-shaped.

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Figures

Fig. 1
Fig. 1
a–c Anterior horn of the lateral meniscus diving underneath the ACL; medial meniscus inserting right in front of the ACL; AH anterior horn of the lateral meniscus, MM anterior horn of the medial meniscus
Fig. 2
Fig. 2
a–b ACL removed from all surrounding soft tissue and cut-off at midsubstance. In this specimen, the anterior horn of the lateral meniscus did not blend into the ACL but inserted completely posterior to the anterior “C”-shaped part of the ACL insertion. c Anterior fibres of the lateral meniscus blend in the anterior “C”-shaped part of the ACL insertion (most common)
Fig. 3
Fig. 3
a–c ACL cut just above the tibial insertion with the “C”-shaped ACL insertion and the lateral meniscus forming a “rain-drop”-like shape. The ACL formed a “ring” structure with the lateral meniscus
Fig. 4
Fig. 4
Tibial ACL footprint with it’s direct “C”-shaped and “ribbon-like” insertion site and its indirect fibres which fan out anteriorly forming a “duck-foot” (red dots)
Fig. 5
Fig. 5
a, b No separate anteromedial and PL bundles could be distinguished during preparation of the ACL and its midsubstance; however, several fibre bundles were identified in some knees
Fig. 6
Fig. 6
a, b Tendon model of “ribbon-like” ligament a flat, b twisted with bundle “effect”
See this image and copyright information in PMC

References

    1. Adachi N, Ochi M, Uchio Y, Iwasa J, Kuriwaka M, Ito Y. Reconstruction of the anterior cruciate ligament. Single- versus double-bundle multistranded hamstring tendons. J Bone Joint Surg Br. 2004;86(4):515–520. - PubMed
    1. Amis AA, Dawkins GP. Functional anatomy of the anterior cruciate ligament. Fibre bundle actions related to ligament replacements and injuries. J Bone Joint Surg Br. 1991;73(2):260–267. - PubMed
    1. Anderson AF, Dome DC, Gautam S, Awh MH, Rennirt GW. Correlation of anthropometric measurements, strength, anterior cruciate ligament size, and intercondylar notch characteristics to sex differences in anterior cruciate ligament tear rates. Am J Sports Med. 2001;29(1):58–66. - PubMed
    1. Arnoczky SP. Anatomy of the anterior cruciate ligament. Clin Orthop Relat Res. 1983;172:19–25. - PubMed
    1. Baer GS, Ferretti M, Fu FH. Anatomy of the ACL. In: Fu FH, Cohen SB, editors. Current concepts in ACL reconstruction. Thorofare: SLACK; 2008. pp. 21–32.

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