Summary Movement Science I: The Knee Complex — Visual Study Guide for DPT Students

The Knee Complex




Tibiofemoral Joint:
 Double condyloid joint with medial and lateral components
 3 degrees of freedom: Flexion/Extension, Medial/Lateral rotation, Abduction/Adduction (or
Valgus and Varum)

Menisci
 Fibrocartilage disks that are thick peripherally and thin centrally
 Peripheral meniscus is innervated and vascularized which promotes healing
 Increase tibial concavity & joint congruency
 Distributes WB forces, reduces friction, provides
shock absorption
 Assume 50-70% of imposed loads
 1-2x WB in walking and stair climbing
 3-4 WB in running
Meniscal Attachments



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, Tibia: Anterior and Posterior horns are firmly attached to tibia, limiting movement, especially on
medial side
Ligamentous: MCL, ACL, PCL (medial mensicus)
Muscular:
Semimembranosus: Medial Meniscus
Popliteus: Lateral meniscus
During knee flexion, for example, the semimembranosus exerts a posterior pull on the medial
meniscus, whereas the popliteus assists with deformation of the lateral meniscus.


The menisci glide posteriorly with knee flexion and anteriorly with knee extension.



Ligaments




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