1. Knee Anatomy and EvaluationBy
Dr. Sue Shapiro

2. Osseous Structures
Formed by the articulations of femur, tibia, and patella.
They form 2 articulations
Tibiofemoral joint
Patellofemural joint
These two articulation are not independent of each other but have a biomechanical relationship

3. Femur Anatomy Distal Aspect Posterior Aspect Condyles Epicondyles
Articulate with patella and tibia.
Posterior Aspect
Epicondyles

4. Tibial Anatomy Tibial Plateus Anterior Portion Medial plateau
Lateral plateau
Anterior Portion
Tibial tuberosity

5. Tibiofemoral & Femoral Joints
Motion in 2 planes
Flexion/Extension & IR/ER
Motion of the tibia on the femur
Femoral Rotation
Flex/Ext above meniscus
IR/ER below meniscus
The Screw Home Mechanism
Results in ER of the femur at terminal Ext.

6. Patellofemoral Joint
The patella a triangular in both sagital and frontal plane
The superior portion ins wider than it distal part
5 distinct facets
super., infer., lateral, medial and odd

7. Osseous Abnormalities
Genus Varus and Valgus
Knock Knee - excessive valgus
Bowleg - excessive varus
Genus Recurvatum - excessive extension
Shallow Trochlear Groove - redisposed to ACL problems
Patella Abnormalities - camel sign

8. Osseous Abnormalities

9. Extra Articular Structures
Extensor Mechanism
Function
to provide deceleration of the patellofemoral articulation at different points along flexion/extension motion.
Lateral retinaculum- static stabilizer
Vastus Lateralis & IT band - dynamic stabilizers
Medial retinaculum- static stabilizer
Vastus Medialis & Adductor Magnus- dynamic stabilizers

10. Extensor Mechanism Extensor Mechanism Function
to provide deceleration of the patellofemoral articulation at different points
Lateral retinaculum- static stabilizer
Vastus Lateralis & IT band - dynamic stabilizers
Medial retinaculum- static stabilizer
Vastus Medialis & Adductor Magnus- dynamic stabilizers

11. Extensor Mechanism
Superior of the patella is supported by the lateral and medial patellofemoral ligament, and inferior by the patello-tibial ligament

12. Q-Angle
The relationship b/t line of pull of the quadriceps and the line of the tendon from the midpoint on the patella to its insertion on the tibial tuberosity.
Normal ranges
Male - 13 degrees
Female - 18 degrees

13. Patella Plica A fold in the synovial lining of the knee Signs
Aggravated by quadriceps exercise
+ Moviegoer’s sign
Pop or snap as the knee is flexed and extended
Point tenderness at medial and lateral retinacular regions

14. Joint Capsule Characteritics
Medial, lateral and anterior aspects arises superior to the femoral condyles and fixates distal to the tibial condyle
Posteriorly the capsule attaches to the posterior margins of the femoral condyles above the Jt. Line & inferiorly, to the posterior tibial condyle
Strength of the capsule is reinforced by the collateral lig. Medially & laterally, the retinaculum medially & laterally, the oblique popliteal lig. and the patella tendon
Capsular attachment of the menisci along the peipheral border of the tibia thus hulding the minisci to the articular surface - CORONARY LIGAMENT

15. Collateral Ligament Medial Collateral Lig. Lateral Collateral Lig.
Deep & Superficial Layers
Primary Function is to protect the knee against valgus
Lateral Collateral Lig.
No attachment to the capsule or meniscus
Primary restrain against varus forces

16. Medial Knee Anatomy Medial Knee muscle Insertion Semimembranosus
Medial Gastroc
VMO
Adductor Magnus
Pes Anerine Group

17. Lateral Knee Anatomy Posteriorlateral Structures Middle Third
Arcuate Lig. Complex
Popliteous Muscle
Lateral Grastroc Head
Arcuate Lig.
Posterior third of the capsular lig.
Middle Third
LCL
Mid-lat capsular lig
Bicep Femoris Muscle

18. Lateral Knee Anatomy Anteriorlateral Aspect Posterior Compartment
Joint Line
Lateral patellar restrainsts
Ilitibial Tract & insertion
Fibular head
Common peroneal nerve
Posterior Compartment
Bicep Femoris
Semimmembranosis
Medial & lateral head gastroc
Popliteal fossa
Popliteal pulse

19. Intra Articular Structures
Menisci
Functions
Distributed WB load over a large surface area
To increase stability
Increase joint congruency by deepening the tibia plateau
Limits abnormal movements

20. Menisci Peripheral Meniscus Medial Meniscus
The outer perimeter is vascular & has the ability to heal itself if torn.
Coronary ligament attach outer perimeter to tibial plateau
Medial Meniscus
Avascular & can not heal if torn
Semimbranosus attaches to the posterior horn
C-shaped & attaches to the MCL and medial capsule

21. Lateral Meniscus O-shaped
Popliteus tendon attaches to the posterior horn & this causes pot. Translation during knee flexion

22. Meniscus Biomechanics Mechanism of Injury Total Excursion (ant/post)
Medial - 6 mm
Lateral - 12 mm
Knee Extension
Kaplan’s Lig. Pulls menisci anteriorly
Knee Flexion
Semimembranosus pulls medial menisci
Popliteus pulls lateral menisci
Mechanism of Injury
Flexion/ Rotation Injury
In flexed position (w/wt) trying to extend the post. Horns get trap and create a bucket handle tear which create pseudo-locking

23. Types of Menisci Most commonly torn in the posterior horn
Unusual for a anterior meniscal tear
Second most common in middle
Names of meniscus tear
Medial- Longitudinal, complex, horizontal. Cleavage
Lateral - Radial, longitudinal, bucket-handle

24. Cruciate Ligaments Anterior Cruciate Lig. Anatomy of ACL Three Bundles
Anteromedial
Intermediate
Posterolateral
Special Teest
Anterior Drawer
Lachman’s Test
Functions of ACL
anterior displacement of tibia to the femur
Stabilizer of rotation

25. Anterior Cruciate Lig Factors affecting ACL rupture Ligament Restrains
Equipment Design
Technique
Fitness
Anatomy
Intercodylar Notch
Narrow Notch
Quick Rotation (ER)
Notchplasty
Braces
Prophylactic & Functional
Ligament Restrains
Anterior Stability
Provides 89% of restraint to anterior displacement
Secondary restraints - 15%
Stress on ACL
Greatest stress (30-0 deg,)

26. Anterior Cruciate Lig Signs and Symptoms
Pivot: deceleration + valgus stress + ER tibia
Hyperextension
Direct contact
80-90% hear/feel “pop/click”
Perception of the knee going out of place
Accumulation of effusion over 2-24 hours

27. Posterior Cruciate Lig.
Anatomy
Two bundles
Posteromedial
Anteromedial
Stability
Provides 95% of restraint to posterior displacement
Function
Prevents posterior displacement of the tibia on femur
Mechanism of Injury
Blow to proximal tibia, or fall on flexed knee with plantar flexion
PCL Testing
Recurvatum
Sag Test
Clancy’s Step Up
Posterior Drawer

28. Bursas Intracapsular Extracapsular Suprapatellar Subpopliteal
Semimembranosus
Extracapsular
Prepatellar
Superficial infrapatellar
Deep infrapatellar

29. Bursas
Functions
During motion of flexion and extension synovial fluid moves throughout the bursal recesses to lubricate the articular surface and the bursas compress compressing fluid in many directions.
Give protection to articular surfaces at the sites of tendon attachment

30. Reflexes and Cutaneous Distribution
Patellar reflex ( L3 - L4)
Medial Hamstrings reflex (L5 - S1)

31. Reflexes and Cutaneous Distribution
Nerves
Tibial Nerve (L4-S3)
Common Peroneal Nerve (L4-S2)
Femoral Nerve (L2-L4)
Saphenous Nerve (L3-L4)

32. Reflexes and Cutaneous Distribution
Blood Supply
Popliteal Artery
Located in popliteal fossa