The Hip: Osteokinematic, Arthrokinematic and Biomechanical Insights

Question 1

The hip has ___ degrees of freedom

Answer 1

3

Question 2

What ligaments strengthen the hip?

Answer 2

iliofemoral, pubiofemoral, ischiofemoral

Question 3

What are the characteristics of the male pelvis?

Answer 3

greater pelvis height, less wide; well defined muscle attachments; long and narrow sacrum; heart-shaped pelvis inlet; acetabulum is large

Question 4

What are the characteristics of the female pelvis?

Answer 4

wider and shorter; indistinct muscle attachments; pelvic inlet is oval; iliolumbar ligament more extensive –> more stable at L5-S1

Question 5

What ligaments provide more mobility for the hip?

Answer 5

Sacrotuberous and sacrospinous

Question 6

Whats does the iliofemoral ligament do?

Answer 6

prevents hyperextension

Question 7

What does the pubofemoral ligament do?

Answer 7

limits excessive extension and abduction

Question 8

Hip flexion/extension is what plane of motion?

Answer 8

saggital

Question 9

Hip flexion has slight ______ glide of femoral head on acetabulum

Answer 9

posterior

Question 10

Hip extension has slight _______ glide of femoral head on acetabulum

Answer 10

anterior

Question 11

What are closed chain motions?

Answer 11

motions working multiple joints with a constant, fixed position –> deep squat, cycling, pull ups

Question 12

Hip abduction is what plane of motion?

Answer 12

frontal

Question 13

Hip abduction has _____ glide of femoral head on the acetabulum

Answer 13

inferior

Question 14

What are the most common MOIs of the hip?

Answer 14

Hyperflexion, Osseus Failure, Flexion-rotation, Axial Rotation/Extension, Excessive Loading, Repetitive Stress

Question 15

Internal/external rotation of the hip is on what plane of motion?

Answer 15

Transverse

Question 16

Hip internal rotation has _____ glide of the femoral head while hip external rotation has _____ glide

Answer 16

posterior; anterior

Question 17

The position of maximum congruency of the hip consists of …

Answer 17

90 degrees of hip flexion and external rotation

Question 18

What is the closed-packed position of the hip?

Answer 18

maximum extension, abduction, internal rotation

Question 19

Where is the coverage of the femoral head the least?

Answer 19

Anatomical position

Question 20

Where is the coverage of the femoral head the most?

Answer 20

flexion, abduction, and external rotation

Question 21

What type of chain is the hip joint’s primary function?

Answer 21

closed-chain

Question 22

What is ligamentum teres?

Answer 22

The ligament of the head of the femur; tubular sheath of synovial lined connective tissue that functions as protective sheath for the acetabular artery

Question 23

What is the center edge angle?

Answer 23

The amount of the femoral head that is covered by the acetabulum; the LARGER the center edge angle the more stability

Question 24

What deepens the acetabular socket?

Answer 24

The acetabular labrum (non weight-bearing)

Question 25

What occurs when the femurs angle of inclination is less than 120 degrees?

Answer 25

coxa vara (closing angle)

Question 26

____ occurs when the femurs angle of inclination is more than 120 degrees

Answer 26

coxa valga (opening angle)

Question 27

What is the normal angle of torsion?

Answer 27

20 degrees

Question 28

What is a femoral angle of torsion greater than 20 degrees known as?

Answer 28

anteversion (opening angle), results in a toed-in gait; compensation at knee

Question 29

What is a femoral angle of torsion lesser than 20 degrees known as?

Answer 29

retroversion (closing angle), results in a toed out gait

Question 30

What is the zone of weakness?

Answer 30

area where the trabeculae do not cross right angles, resulting in less reinforcement which leads to more potential for injury

Question 31

The force of gravity and ground reaction produce a ______ force on the shaft of the femur

Answer 31

bending

Question 32

What is the strongest hip flexor?

Answer 32

illiopsoas

Question 33

What are the primary hip flexors in the body? (anterior group)

Answer 33

illiopsoas, pectinous, rectus femoris, and sartorius

Question 34

What are the hip extensors of the body? (posterior)

Answer 34

gluteus maximus, biceps femoris, semitendinous, semimembranosus, and external rotators

Question 35

What are the hip abductors of the body? (lateral)

Answer 35

gluteus medius, gluteus minimus, TFL, and external rotators

Question 36

What are the hip adductors of the body? (medial)

Answer 36

adductor brevis, longus, and magnus and gracilis

Question 37

What is the lumbar plexus?

Answer 37

formed by anterior rami of spinal nerves L1 through L4 and some fibers from T12

Question 38

What is the sacral plexus?

Answer 38

formed by anterior rami of L4, L5, S1 through S4

Question 39

What is the sciatic nerve?

Answer 39

goes under piriformis and up to sciatic notch