Unit 2- Hip

Question 1

What is the position of max congruence between femur and acetabulum when NWB

Answer 1

hip flexion, abduction, slight ER

Question 2

what is the close packed position of the hip

Answer 2

hip extension, IR, abduction

Question 3

angle of inclination

Answer 3

angle between the shaft and neck, normally 125

decreases during WB

Question 4

acetabular dome

Answer 4

primary wb surface of acetabulum

Question 5

center edge angle

Answer 5

angle formed by center of head of femur and edge of acetabulum connection with femur head

Question 6

how to increase stress on the acetabulum

Answer 6

decrease center edge angle, acetabular anteversion

Question 7

how to decrease stress on the acetabulum

Answer 7

increase contact area (happens during gait)

Question 8

bony adaptation to weight bearing

Answer 8

tubecular areas
primary: medial- vertical compressive forces
lateral- oblique; response to shear/tensile forces
secondary: tensile and compressive, in shaft

Question 9

zone of weakness in femur

Answer 9

where no compressive forces are usually found, vulnerable to dislocation

Question 10

what are the roles of the hip joint ligaments

Answer 10

iliofemoral: limit extension, lateral rotation
pubofemoral: limit extension, lateral rotation
ischiofemoral: limit extension, adduction, medial rotation

Question 11

what is the alignment of the bony landmarks of the pelvis in neutral

Answer 11

asis in line with psis in line with pubic symphysis

Question 12

Anterior/posterior pelvic tilt

Answer 12

named by movement of ASIS

sagittal plane

Question 13

lateral pelvic tilt

Answer 13

aka pelvic hike/drop
named by movement of side opposite the WB limb (muscles of stance leg control motion of far side of pelvis
frontal plane, A/P axis in middle of femoral head of stance leg

Question 14

forward/backward pelvic rotation

Answer 14

transverse plane

named by side opposite the WB limb

Question 15

lumbopelvic rhythm

Answer 15

describes how lumbar spine is moving relative to pelvis
ipsidirectional- maximize angular displacement of the entire trunk relative to lower extremity
contradirectional- keeps supralumbar trunk stable

Question 16

pelvifemoral motion

Answer 16

combined motion of pelvis and femur increases the available motion
ex- touching toes, anterior pelvic tilt
hip abduction, tilt hip and side bend to increase abduction

Question 17

Force couple for anterior pelvic tilt

Answer 17

iliopsoas (reverse motion) and erector spinae

cocontract to contribute to rotation in same direction

Question 18

force couple for posterior pelvic tilt

Answer 18

glut max, hamstrings, rectus abdominus

Question 19

function of hip adductors

Answer 19

aim to bring the hip to about 60 degrees flexion
more flexion–extensor
more extension–flexor

Question 20

what limits hip flexion with knee flexed

Answer 20

posterior and inferior capsule, glut max

Question 21

what limits hip flexion with knee extended

Answer 21

hamstrings

Question 22

what limits hip extension with knee extended

Answer 22

iliofemoral ligament, anterior capsule, pubofemoral and ischiofemoral, iliopsoas

Question 23

what limits hip extension with knee flexed

Answer 23

rec fem

Question 24

what limits abduction

Answer 24

adductor muscles, pubofemoral ligament

Question 25

what limits adduction

Answer 25

ITB abductor muscles (TFL and glut med)

Question 26

what limits internal rotation

Answer 26

ischofemoral ligament, external rotator muscles (glut max and piriformis)

Question 27

what limits external rotation

Answer 27

iliofemoral and pubofemoral, internal rotator muscles (TFL, glut min)

Question 28

what is normal acetabular anteversion

Answer 28

20 degrees

Question 29

coxa vara

Answer 29

less than 125 degrees angle of inclination

• increased moment arm for hip adductor force
• more stability
• increases bending moment are, increases bending moment, increases shear force across femoral neck
• decreased functional length of hip abductor

Question 30

coxa valga

Answer 30

more than 125 degrees angle of inclination

• decreased bending moment arm, decreases bending moment and shear force across femoral neck
• increases function length of hip abductor muscle
• decrease moment arm for hip abductor force
• alignment may favor hip dislocation (more mobility)