Anatomical description of the posterolateral corner of the knee: a descriptive study based on cadaveric dissection and E12 sheet plastination

Abstract

Background: major traumatisms affecting the knee usually associate posterolateral instability, which makes difficult the recovery of other lesions such as anterior cruciate ligament avulsion. The more anatomical the reconstruction of the posterolateral stabilisers the better biomechanical outcome is achieved. In order to provide an accurate diagnoses and treatment, basic knowledge must be pursued, being anatomy the first stage on a multi-specialist approach. Objectives: to perform a precise description of the major stabilisers of the posterolateral corner of the knee, these being the lateral collateral ligament, the popliteus tendon and the popliteofibular ligament. A structure related to the capsule will be studied independently in order to determine its existence and components, defined by some as a midthird lateral capsular ligament or an anterolateral ligament. Design: descriptive observational exploratory study, based on a series of cases. Methods: macro and microdissection was performed on three fresh human knee specimens. E12 sheet plastination technique was applied to two more fresh human knees. Slices were then scanned with a 4K high definition scan for up-close study. Results: all four structures were identified by dissection and also by sheet plastination. A description of each of them could be specified. Connexions between the popliteus

tendon and the fibula have been demonstrated. Fibrous tissue compatible with the so- called midthird lateral capsular ligament was expressly reported.

Conclusions: combined use of macro-microdissection technique and E12 (Biodur®) sheet plastination have allowed us a better comprehension of the complex anatomy of the posterolateral compartment of the knee. Nevertheless, our sample value needs to be increased in order to corroborate our results and to evidence possible anatomical variations that may need to be taken into account