1. Knee Anatomy

2. Knee Joint
The most poorly constructed joint in the body. Femur round, tibia flat.
Comprised of four bones.
Femur
Tibia
Fibula
Patella

3. Femur Medial and Lateral Condyles- distal ends of the femur.
Largest bone in the body

5. Femur Landmarks to know Add. Tubercle Medial and Lateral epicondyles
Medial and lateral condyles
Intercondylar fossa
Patella fossa (not shown)

6. Tibia and Fibula

9. Fibula
Landmarks to know
Apex
Head
Neck
Lateral Maelleolus

10. Tibia Landmarks to know Intercondylar eminence
Medial and lateral condyles
Tibial tuberosity

13. Patella
Patella tendon- attaches to the anterior of the tibia. (tibial tuberosity)
Quadriceps tendon-attaches the quadriceps to the patella.

14. Joints Tibiofemoral Patellofemoral Superior Tibiofibular
Largest joint in body
Patellofemoral
Patella contains the thickest cartilage found in the body
Superior Tibiofibular
Any movement here is due to movement at the ankle

15. Knee Stabilizers PRIMARY SECONDARY Medial Collateral Ligament
Lateral Collateral Ligament
Anterior Cruciate Ligament
Posterior Cruciate Ligament
SECONDARY
Medial Meniscus
“C” shaped
Lateral Meniscus
“O” shaped

17. Cruciate Ligaments Major stabilizing ligaments in the knee
Anterior Cruciate Ligament (ACL)-prevents the tibia from sliding out in front of the femur
Injuries caused by hyperflexion, internal rotation, hyperextension

19. ACL
Has Two Bundles
Anteromedial
Tight in flexion and extension
Posterolateral
Tight in extension
Ligament is most lax between 30 – 60 degrees flexion

20. Posterior Cruciate Ligament
Prevents posterior translation of the tibia on the femur
Resists hyperextension of knee
Runs from posterior tibia to anterior femur

21. PCL Fibers are tightest around 30 degrees flexion
Posterolateral fibers are the last to become tight
Two times stronger than ACL

22. Collateral Ligament
Medial Collateral Ligament (MCL)- connect the tibia and the femur.
A force from the lateral side could cause a tear.
Valgus force

23. Medial Collateral Ligament
Two layers
Deep layer is actually a thickening of the joint capsule that blends into the medial meniscus
Superficial layer is what we view as the MCL

24. Collateral Ligament
Lateral Collateral Ligament (LCL)- connect the fibula to the femur.
A force from the medial side can cause a tear of the LCL
Varus force

25. Lateral Collateral Ligament
Attaches to head of fibula
Prevents excessive varus and IR forces
Tightest in extension, loosest after 30 degrees flexion

26. Cartilage Articulate Cartilage-covers the moving parts of the knee.
Chronic damage to articulate cartilage leads to arthritis.

28. Cartilage
Meniscus- half moon shaped cartilage lying between the knee joint.

29. ARTICULAR DISCS
Medial Meniscus
Lateral Meniscus

30. Meniscal Blood Supply Each Meniscus has 3 zones
Red Zone
Outer 1/3: good blood supply
Red/White Zone
Middle 1/3: minimal blood supply
White Zone
Inner 1/3: avascular (no blood supply)
Implications for injury?

31. Meniscal Blood Supply