KNEE to KNOW

1. KNEE-
ANATOMY
by A.Arputha Selvaraj

2. The Knee
• Bones
o Femur
o Patella
• Largest Sesamoid bone in human body
o Tibia
o Fibula
• Non-weight bearing bone
• Articulations
o Four Articulations
• Femur and Tibia
• Femur and Patella
• Femur and Fibula
• Tibia and Fibula

3. • Meniscus
o Two oval fibrocartilages that sit in the tibia
• Semi-lunar (half moon shape)
o Stabilize the knee
• Especially the medial, when the knee is flexed at 90 degrees
o Medial
• C-shaped
• Attach to the tibia, joint capsule by the coronary ligament,
and the semimenbranous muscle (hamstring)
o Lateral
• O-shaped
• Attached to the tibia, loosely to capsule, and popliteal
tendon, and ligament of Wristberg
o Blood Supply
• Divided into 3 circumferential zones
o Red –Red
o Red-White
o White-White
• Avascular

4. 3 Zones of Meniscus

5. • Stabilizing Ligaments
o Account for a considerable amount of knee stability
o Two ligamentous bands that cross one another within the joint
capsule of the knee
• Anterior Cruciate Ligament (ACL)
o 3 twisted bands
o Prevents the femur from moving posteriorly weight
bearing and anteriorly non-weight bearing.
o Stabilizes the tibia from excessive internal rotation (IR)
• Posterior Cruciate Ligament (PCL)
o Resists IR of the tibia
o Prevents hyperextension of the knee

6. ACL & PCL

7. Common Cause of ACL
Tear

8. Common Cause of PCL
Tear
Situations in which the PCL can tear
include -
excessive hyperflexion (forced
bending), eg falling onto the shin with
a bent knee and foot pointed
dashboard injury in a car - where the
knee is bent to a right angle and a
sudden force drives the tibia
backwards

9. • Medial Collateral Ligament
o Superficial ligament(MCL) is separate from the deeper capsular
ligament.
o Attaches above the join line on the medial epicondyle of the
femur and below on the tibia – Just beneath the attachment of
the pes anserinus (hamstring tendons)
o Deep medial capsular ligaments
• Primary purpose are to attach the medial meniscus to the
femur and to allow the tibia to move on the meniscus
inferiorly
• Lateral Collateral Ligament
o Size of a pencil
o Attached to lateral epicondyle of the femur and to the head of
the fibula.
o Taut during knee extension but relaxed during flexion

11. More Structures of the
Knee
• Joint Capsule
o Knee joint is surrounded by the LARGEST joint capsule in the
body.
o Contains: infrapatellar pouch, fat,pad, and bursae, MCL, and
other ligaments.
o Divided into Four regions – are reinforced by other anatomical
structures
• Posterolateral & medial
• Anterolater al & medial

12. • Knee Musculature
o 13+ Muscles
o Movements of the Knee
• Knee Flexion & Extension
• External & Internal Rotation
• Bursae
o Reduce friction
o 2 dozen have been identified in the knee
• Fat Pads
o Several pads located around the knee
o Infrapatellar fat pad is the largest
• Nerve & Blood Supply

14. Specific Injuries
• Medial & Lateral Collateral Sprain
o Hit from opposite side of leg
• ACL & PCL Sprain
o ACL= lower leg is rotated while the foot is fixed (jumping)
o PCL=fall with full weight on the anterior aspect of the bent knee with
the foot in plantar flexion (sliding)
• Meniscal Lesions
o Most common= weight bearing combined with a rotary force while
running
• Patellar Conditions
o Patellar orientation predisposes you to have certain types of injuries
• Acute patellar subluxation or dislocation
• Chondromalacia
o Softening and deterioration of the articular cartilage on the
back of the patella
o Three stages
• Patellofemoral Stress Syndrome
o Some lateral deviation of the patella as it tracks in the
femoral groove

15. MCL & LCL
Sprain

16. Meniscal Lesions

17. Patellar
Tracking

18. Patellar Examination
• The Q-Angle
o Quadriceps angle
o Normal is 10’ Males / 15’ Females
o 20’ (+) predisposed to
• patellar subluxation/dislocation

19. • Extensor Injuries
o Osgood-Schlatter Disease
• Pain at the attachment of the patellar tendon to the tibial
tubercle
• Can lead to avulsion fracture
o Larsen-Johansson Disease
• Occurs at the inferior pole of the patella
• Excessive repeated strain on the patellar tendon
o Patellar Tendinitis (Jumper’s/Kicker’s Knee)
• Repetitive trauma
• Extreme tension on the knee extensor muscle complex
• Painful at patellar or quadriceps tendon
• Iliotibial Band Friction Syndrome (runner’s
knee)
o General expression for many repetitive and overuse conditions
o Malalignment and structural assymetries of the foot and lower
leg.

20. Extensor
Injuries

21. Patellar tendonitis can be classified by the following
techniques:
Stage 0 - No Pain
Stage 1 - Pain only after intense sports activity; no undue
functional impairment
Stage 2 - Pain at the beginning and after sports activity;
still able to perform at a satisfactory level
Stage 3 - Pain during sports activity; increasing difficulty in
performing at a satisfactory level
Stage 4 - Pain during sports activity; unable to participate
in sport at a satisfactory level
Stage 5 - Pain during daily activity; unable to participate in
sport at any level

22. Knee Joint Rehabilitation
• General Body Conditioning
• Weight Bearing
• Knee-Joint Mobilization
• Flexibility
• Muscular Strength
• Neuromuscular Control
• Bracing / Taping
• Functional Progression
• Return to Activity

23. Thank you
email me : arputhaselvaraj@gmail.com