The knee joint

Question 1

What is the anatomical name for the knee joint?

Answer 1

Tibiofemoral

Question 2

What are the main functions of the knee joint?

Answer 2

Weight bearing, locomotion an stability

Question 3

Describe the medial and lateral condyles of femur

Answer 3

Convex is shape and rest of the tibia
Medial condyle slightly larger
Lateral condyle extends more laterally

Question 4

What are the femoral condyles?

Answer 4

Form the trochlear groove that provide articulating surface of the demure

Question 5

What are epicondyles?

Answer 5

On condyles

Attachment points fo ligaments

Question 6

What is the main function of the patella

Answer 6

Creates improved angle of pull resulting in greater mechanical advantage of quads during knee extension

Question 7

Describe the patella

Answer 7

Triangular sesamoid bone embedded in quadriceps and patellar tendon

Question 8

What happens to the patella when the knee flexes?

Answer 8

Moves down and posterior, over 2 times its length

Question 9

What are the normal Q values?

Answer 9

12 degrees for males 18 degrees for females

Question 10

What are the functions of menisci

Answer 10

Aid in lubrication and nutrition of joint
Deepen contact surface which increases joint stability
Shock absorption
Protect articular cartilage

Question 11

Describe menisci

Answer 11

Fibrocartliage discs located on tibial plateaus

Attached to the tibial condyles by the medial and lateral coronary ligaments

Question 12

Coronary ligament

Answer 12

joins menisci to head of tibia medially and laterally

Question 13

Transverse ligament

Answer 13

links anterior surfaces of both menisci together

Question 14

Medial (tibial) collateral ligament

Answer 14

strong thick ligament from medial epicondyle of femur to medial tibial condyle

Question 15

Lateral collateral ligament

Answer 15

narrow rounded cord from lateral epicondyle of femur to lateral surface of head of fibula
prevents lateral separation and sideways movements of articulating surfaces

Question 16

What is the main function of cruciate ligaments?

Answer 16

Prevent anterior/posteror dislocation and rotation of tibia on femur

Question 17

Anterior cruciate ligament (ACL)

Answer 17

runs posteriorly and laterally from anterior intercondylar eminence to medial side of lateral condyle of femur
Provides ~86% of stability preventing anterior displacement of the tibia

Question 18

Posterior cruciate ligament (PCL)

Answer 18

runs anteriorly and medially from the posterior intercondylar eminence to lateral and front part of medial epicondyle

Stronger than ACL, injured less frequently

Question 19

What type of joint is the knee joint?

Answer 19

Primarily a hinge

Ginglymus

Question 20

Movements of the knee

Answer 20

Flexion and extension

Question 21

What is the screw home principle of the knee

Answer 21

Considered a key element to knee stability for standing upright

Rotation between Femur & Tibia

If foot fixed on ground and tibia is weight-bearing, femur will involuntarily internally rotate and move posteriorly on tibia during last 30° of extension – locks knee into a ‘closed pack position’.

Consequently, femur must externally rotate and move forward during the initial stages of flexion.

Question 22

Reasons behind the screw home principe

Answer 22

Unequally sized femoral condyles - lateral condyle glides over a greater distance which causes as internal rotation
Direction of the collateral ligaments - medial becomes stretched less rapidly than the lateral in extension causing internal rotation

Question 23

What are the causes of patellofemoral pain syndrome?

Answer 23

Overactivity

Muscle flexibility or strength imbalance