Patella
-Triangle Shaped Sesamoid
-Bone in tendon of the quad (Specifically Rec Fem)
Sesamoid
A bone embedded in a tendon (usually shaped like a sesame seed)
Patella (Anterior View)
-Base (the flat superior edge)
-Apex (the more pointed inferior edge)
Patella (Posterior View)
-Vertical Ridge
-Medial Articular Facet
-Lateral Articular Facet
*Facets articulate with the patellar surface of the femur and the medial and lateral condyles of the femur
What are the three articulations of the knee?
Available Movements of the Knee
-Flexion
-Extension
-Internal Rotation (Limited)
-External Rotation (Limited)
*Rotation occurs ONLY when Knee is flexed
Patellofemoral Joint
-Medial and Lateral facets of the patella articulate with the patellar surface of the femur
-Synovial
-Plane
-Patella moves down (inferiorly) during flexion and up (superiorly and laterally) during extension
*The lateral femoral condyle projects farther (anteriorly) than the medial femoral condyle
*This more anterior prominence of the lateral femoral condyle prevents the patella from tracking too far laterally
Tibiofemoral Joint
-Medial and Lateral Condyles of the tibia articulate with the medial and lateral femoral condyles
-Synovial
-Modified Hinge (because it allows for some rotation)
-Biaxial
The __________ femoral condyle projects farther (anteriorly) than the __________ femoral condyle
Lateral, Medial
This more anterior prominence of the lateral femoral condyle prevents the _____________ from tracking too far ___________.
Patella, Laterally
Valgus
Lateral deviation of the distal bone(s) of a joint
-When knee is fixed and the tibia (specifically the distal end) has deviated laterally (relative to knee)
-a.k.a. Knock-Knee
Varus
(return) Medial deviation of the distal bone of a joint
-When the knee is fixed and the tibia (specifically the distal end) has deviated medially (relative to the knee)
-a.k.a. bow-leg
Lateral Collateral Ligament (LCL) (fibular collateral ligament)
-Attached: lateral epicondyle of the femur - fibular
head
-checks/restricts VARUS deviation
-“pencil-like” (easier to palpate)
Medial Collateral Ligament (MCL) (tibial collateral ligament)
-Attaches: medial epicondyle of femur - medial condyle of the tibia
-checks/restricts VALGUS deviation
-it is a flat thickening of the joint capsule
-the deep fibres of the ligament are attached to the medial meniscus
Anterior Cruciate Ligament (ACL)
-Attaches: medial epicondyle of the femur - medial condyle of the tibia
-checks/restricts valgus deviation
-it is a flat thickening of the joint capsule
-the deep fibres of the ligament are attached to the medial meniscus
Posterior Cruciate Ligament
-Attaches: posterior intercondylar area of the tibia - anterior and lateral side of the medial femoral condyle
-slack when the knee is extended and taut when the knee is in full flexion
-checks posterior translation of the tibia on the femur (or anterior translation of the femur on the tibia) and knee flexion
Cruciate ligaments are named for __________________.
Where they attach on the tibia. (i.e. the anterior cruciate ligament attaches anteriorly on the tibia)
Medial and Lateral Coronary Ligaments (Attachments)
-Attach the medial and lateral menisci to their respective tibial plateaus
Menisci of the knee
-C-shaped plated of fibrocartilage attached to the articular surfaces of the tibia
-Centre is thinner than the outer edges
-Slightly mobile and and aid in the spreading of synovial fluid during knee movement
-Function: shock absorbers
-Function: deepen the articulation (provide more stable articulation between the tibia and the femur
-ends of the C-shape are called horns
-medial meniscus is attached to the medial collateral ligament
What is the terrible triad?
Anterior Cruciate Ligament (ACL)
Medial Collateral Ligament (MCL)
Medial Meniscus
2 menisci are connected anteriorly by the _____________.
Transverse Ligament of the Knee
Menisci of the knee (Function)
-Function: shock absorbers
-Function: deepen the articulation (provide more stable articulation between the tibia and the femur
Menisci of the knee (Attachments)
-C-shaped plated of fibrocartilage attached to the articular surfaces of the tibia
-Medial meniscus is attached to the medial collateral ligament
Posterior Cruciate Ligament (Checks/Restricts)
-Checks posterior translation of the tibia on the femur (or anterior translation of the femur on the tibia) and knee flexion