- PCL is approximately twice as strong and twice as thick as the normal ACL (therefore less commonly injured);
- size: 13 mm, its length, 38 mm, (approximates that of ACL);
- PCL originates from the antero-lateral aspect of medial femoral condyle in the area of intercondylar notch;
- it origin is much more anterior than that of ACL;
- ref: Topography of the Femoral Attachment of the Posterior Cruciate Ligament
- tibial atatchment is not intra articular, but over back of tibial platuea, it is approximately 1 cm distal to the joint line;
- Tibial Insertion of the Posterior Cruciate Ligament: A Sagittal Plane Analysis Using Gross, Histologic, and Radiographic Methods
- Morphology of the Tibial Insertion of the Posterior Cruciate Ligament
- ligament can be partially separated into an anterolateral and posteromedial;
- anterolateral bundle:
- represents about 65% of the substance of the PCL;
- in flexion the anterolateral band is tight and the posteromedial band is lax;
- most surgeons seek to reconstruction the anterolateral portion of the PCL noting its larger size and more important functional role;
- posteromedial bundle:
- comprimises 35% of the PCL;
- in extension the anterolateral band is lax and posteromedial band is tight;
- ref: Changes in knee laxity and ligament force after sectioning the posteromedial bundle of the posterior cruciate ligament.
- ligaments of Humphrey and Wrisberg:
- major blood supply: from middle genicular artery;
- nerve supply: tibial nerve (significant mechanoreceptors)
- function and natural history:
- provides 95% of total restraining force to straight posterior translation of the tibia relative to femur;
- secondary restraints to posterior displacement of the tibia include posterolateral capsule, popliteus, MCL, and POL;
- secondary action includes resistance to varus, valgus, and external rotation;
- PCL is more verticle in extension and more horizontal in flexion;
- hyperflexion mechanism: most common mechanism for an isolated PCL injury:
- hyperflexion causes the large anterolateral component to fail but spares the posteromedial band (which is loose in flexion);
- this type injury does not involve the secondary restraints and does well with non operative treatment;
- dashboard injury (from MVA): may result in severe combined injuries;
- left untreated PCL ruptures may lead to chronic patello femoral as well as medial compartment arthrosis;
- Epidemiology of posterior cruciate ligament injuries.
- Effect of Posterior Cruciate Ligament Deficiency on In Vivo Translation and Rotation of the Knee During Weightbearing Flexion
- A clinically relevant assessment of posterior cruciate ligament and posterolateral corner injuries. Evaluation of isolated and combined deficiency.
- Effects of knee flexion angle and loading conditions on the end-to-end distance of the posterior cruciate ligament: a comparison of the roles of the anterolateral and posteromedial bundles.
Current Concepts Review. Injuries of the Posterior Cruciate Ligament.
Posterior Cruciate Ligament. A Demonstration in Six Patients and a Study of Anatomical Specimens.
Strain measurement of the human posterior cruciate ligament. SW Arms et al. Trans Orthop. Res. Soc. Vol 9. 1984. p 355.
Original Text by Clifford R. Wheeless, III, MD.
Last updated by Data Trace Staff on Tuesday, October 13, 2015 7:25 am