MCL Anatomy

This section describes the MCL anatomy, including the bundles represented in the model and the femoral and tibial insertion sites.

General Description

This lab models the MCL as three distinct bundles. Two of those bundles compose the superficial MCL (sMCL), and one bundle represents the deep MCL (dMCL). The sMCL has one femoral and two two tibial attachments [LaP07], one tibial insertion is more proximal to the joint line (psMCL), and the other is more distal to the joint line (dsMCL). The tibial attachments are used to differentiate the two sMCL bundles.

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Fig. 10 The insertions of the MCL [LaP07].

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Fig. 11 The insertions of the dMCL [LaP07].

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Fig. 12 The insertions of the dMCL [LYG+10].

Proximal sMCL

  • Femoral insertion: the attachment is located in a depression that is slightly proximal and posterior to the medial femoral epicondyle. The center of the attachment side is 6.4 mm (3.9 to 9.6 mm) from the medial femoral epicondyle, and 26.8 mm (13.1 to 32.2 mm) from the femoral joint line (assumed to be in extension). The insertion area is approximately 94.1 mm^2 (60.1 to 143.8 mm^2) [LaP07] (appendix).
  • Tibial insertion: the tibial insertion is described as connecting to the semimembranosus tendon, and the tendon inserts into the tibia. This is modeled as a direct attachement of the psMCL into the tibia (this describes the semimembranosus tendon tibial attachment from [LaP07]). The center of the attachment is located 12.2 mm (8.8 to 15.3 mm) to the tibial joint line. The attachment area is approximately 221.5 mm^2 (104.7 to 609.2 mm^2).

Distal sMCL

  • Femoral insertion: the attachment is located in a depression that is slightly proximal and posterior to the medial femoral epicondyle. The center of the attachment side is 6.4 mm (3.9 to 9.6 mm) from the medial femoral epicondyle, and 26.8 mm (13.1 to 32.2 mm) from the femoral joint line (assumed to be in extension). The insertion area is approximately 94.1 mm^2 (60.1 to 143.8 mm^2) [LaP07] (appendix).
  • Tibial insertion: just anterior to the posteromedial crest of the tibia. The distance from the center of the attachment to the joint line is approximately 61.2 mm (52.4 to 70.5 mm). The attachement area is approximately 294.3 mm^2 (212.4 to 356.8 mm^2) [LaP07] (appendix).

Deep MCL

The deep MCL (dMCL) has an insertion into the medial meniscus [LaP07][LYG+10]. The definition of this insertion is described in dMCL and Meniscus Ties.

  • Femoral insertion: width (anterior-posterior) 9.9 ± 3.2 mm, with an area of 71.9 ± 14.8 mm^2, and the center of the insertion area is 20.5 ± 4.2 mm from the femoral joint line, and 13.0 ± 2.7 mm from the medial femoral epicondyle [LYG+10].
  • Tibial insertion: width (anterior-posterior) 18.0 ± 4.0 mm, with an area of 63.6 ± 13.4 mm^2, and the center of the insertion area is 6.5 ± 1.3 mm inferior to the tibial joint line [LYG+10].

Note

This section references [LaP07], and the appendix for this article can be found on the journal’s website. The appendix appears to be freely available, so a subscription to the journal is not needed.

[LaP07](1, 2, 3, 4, 5, 6, 7, 8, 9) Robert F. LaPrade. The Anatomy of the Medial Part of the Knee. The Journal of Bone and Joint Surgery (American), 89(9):2000, September 2007. URL: http://jbjs.org/cgi/doi/10.2106/JBJS.F.01176, doi:10.2106/JBJS.F.01176.
[LYG+10](1, 2, 3, 4) Fang Liu, Bing Yue, Hemanth R. Gadikota, Michal Kozanek, Wanjun Liu, Thomas J. Gill, Harry E. Rubash, and Guoan Li. Morphology of the medial collateral ligament of the knee. Journal of orthopaedic surgery and research, 5(1):69, 2010. URL: https://josr-online.biomedcentral.com/articles/10.1186/1749-799X-5-69.