Joints

Question 0

What is the hip bone reinforced by?

Answer 0

• anteriorly/posteriorly - iliofemoral ligament - prevents hyperextension of hip
• anteriorly/inferiorly - pubofemoral ligament - prevents overabduction
• posteriorly - ischiofemoral ligament

Question 1

What is the hip joint

Answer 1

multi-axial ball-and-socket synovial

• stability over wide range of movement
• body weight is transmitted through hip bones to head/neck of femurs when standing

Question 2

Joint capsule of hip

Answer 2

• covers proximal 2/3 of femur neck posteriorly

- synovial membrane forms bursa for obtruator externus tendon

Question 3

what is the orbicular zone?

Answer 3

deep fibers mostly in posterior part of capsule wind around neck

Question 4

Femur Head

Answer 4

• surrounded by articular cartilage (except pit or fovea for the ligament of the head of femur)

Question 5

Lunate surface of acetabulum

Answer 5

rim of acetabulum (semilunar articular part) covered with articular cartilage

Question 6

Depth of Acetabulum

Answer 6

• increased by fibrocartilaginous acetabular labrum and transverse acetabular ligament (bridges acetabular notch)
• more than 1/2 of femur head fits in acetabulum

Question 7

What are the movements at the hip joint?

Answer 7

• flexion/extension, abduction/adduction, medial/lateral rotation, and circumduction
• degree of flexion/extension possible at hip depends on knee position
• during extension of hip, fibrous layer of joint capsule is taut
• abduction is freer than adduction
• lateral rotation is more powerful than medial

Question 8

What type of joint is the knee?

Answer 8

Hinge synovial

Question 9

Type of movement at knee joint?

Answer 9

• flexion/extension

- some gliding, rolling, and rotation about a vertical axis

Question 10

Stability of knee joint

Answer 10

Surround muscles and tendons, ligaments connecting femur and tibia

• fibula is not involved
• most important muscles for stability = quadriceps (vastus lateral is and medialis)

Question 11

Knee joint capsule

Answer 11

• external fibrous layer (joint capsule) - quadriceps tendon, patella, and patellar ligament serve as capsule anteriorly
• internal synovial membrane - lines all internal surfaces of cavity not covered by cartilage

Question 12

Articular genu muscle

Answer 12

• deep to vastus intermedius

- attaches synovial membrane and retracts suprapatellar bursa during extension of knee

Question 13

Movements of knee joint

Answer 13

• flexion/extension

- some rotation with flexed knee

Question 14

“Unlock” knee

Answer 14

• popliteus contracts

- rotates femur about 5 degrees on tibial plateau so flexion of knee occurs

Question 15

Knee “lock”

Answer 15

Passively locks because of medial rotation of femur on tibia

Question 16

Superior tibiofibular joint

Answer 16

• Plane synovial
• slight gliding movements during dorsiflexion of foot
• between flat facet on fibular head and a facet located posterolaterally on lateral tibial condyle
• tense joint capsule surrounds joint