Hip

Question 1

What is the angle of inclination at birth? As an adult?

Answer 1

140-150 degrees

125 degrees

Question 2

Coxa vara

Answer 2

Angle is less than 125 degrees.
Disturbs length tension relationship of gluteus medius
Positive: Increased moment arm for hip abductor force, alignment can improve joint stability.
Negative: increase moment arm bending and sheering forces across the femoral neck, especially bad for people with osteoporosis because their femoral neck is already weak.
Overall decreased functional length of hip abductor muscles (going to be shorter), going to be harder to control trendelenberg gait

Question 3

Coxa valga

Answer 3

Angle is greater than 125 degrees
Disturbs length tension relationship of gluteus medius
Positive: decreased bending moment arm and decreases shearing forces across femoral neck
Increased functional length of hip abductor muscles
Negative: decreased moment arm for hip abductor force
Alignment may favor joint dislocation

Question 4

Normal torsion angle of femoral neck

Answer 4

10-15 degrees anteversion

Question 5

Excessive anteversion

Answer 5

Greater than 15 degrees
Femoral head moves anteriorly and greater trochanter moves posteriorly. Shaft of femur does not move.
Disturbs length tension relationship of gluteus medius.
If body compensates, the whole lower extremity will internally rotate and person will walk with a toes in position. If child compensates then they correct for that proximally and maintain length tension relationship (good).
Can go undiagnosed if child doesn’t compensate

Question 6

Retroversion

Answer 6

Less than 10 degrees
Femoral head moves posteriorly and greater trochanter moves anteriorly
Out toeing

Question 7

Femoral head is located

Answer 7

Just inferior to middle 1/3 of inguinal ligament
Head has a fovea with ligamentum teres
Branch of obturator artery brings small blood supply to femoral head

Question 8

Acetabular labrum

Answer 8

Fibrocartilage

Deepens the socket

Question 9

Cartilage of the dome is thickest

Answer 9

Along the superior/inferior region because this is where weight bearing happens

Question 10

Iliofemoral ligament

Answer 10

AIIS to intertrochanteric line
Full extension stretches the ligament and full ER stretches the lateral bundle of the ligament
If someone cuts this ligament you will get huge increase in extension, if it scars down you won’t get any extension
One of the strongest ligaments in the body

Question 11

Ischiofemoral ligament

Answer 11

Ischium to greater trochanter
Superficial fibers get taut with extension and IR
Superior fibers get taut with adduction
Inferior fibers get taut with flexion

Question 12

Pubofemoral ligament

Answer 12

Anterior/inferior rim of acetabulum, superior pubic ramus and then blends with medial fibers of iliofemoral ligament
Taut with hip extension and abduction

Question 13

Closed pack position of the hip

Answer 13

Extension, IR, abduction

Question 14

Position of maximal congruency for the hip

Answer 14

90 degrees hip flexion, moderate ER, and abduction

Little passive tension to the ligaments in this position

Question 15

Full hip flexion

Answer 15

120 degrees with knees bent
80 degrees with knees straight because hamstring is short

If you bend your knee and it’s still that still happens it’s a capsular issue, have to mobilize here

Slackens most ligaments but stretches inferior capsule

Question 16

Hip extension

Answer 16

20 degrees beyond neutral with knee straight
Limited to neutral with knee bent (because rectus is on full stretch)
Stretches all ligaments and hip flexor muscles

Question 17

Abduction

Answer 17

40 degrees

Limited by tension in the pubofemoral ligament

Question 18

Adduction

Answer 18

25 degrees beyond neutral

Limited by hip abductor muscles, contralateral limb, and superficial fibers ischiofemoral ligament and ITB

Question 19

Hip internal rotation

Answer 19

35 degrees
Unchanged by flexion/extension of hip
Limited by piriformis and parts of the ischiofemoral ligament

Question 20

Hip external rotation

Answer 20

45 degrees
Limited with increased amounts of hip flexion (because soft tissues in post gluteal region are wound up in this position)
Limited by TFL and lateral fibers of the iliofemoral ligament

Question 21

Ipsidirectional lumbopelvic rhythm

Answer 21

Pelvis and spine rotate in the same direction

Question 22

Contra-directional lumbopelvic rhythm

Answer 22

Pelvis rotates in one direction while lumbar spine rotates in the opposite direction
So pelvis goes forward into anterior tilt and lumbar spine goes back into extension

Osteokinematics of pelvis on femoral movement all use contra-direction lumbopelvic rhythm

Question 23

Force couple anterior tilt

Answer 23

Between erector spinae in the back and iliopsoas and rectus femoris in the front
Increase in lumbar lordosis
Greater lordosis will increase compression forces at the facet joints

Question 24

Force couple posterior tilt

Answer 24

Between the abdominals in the front and gluts and hamstrings in the back
Reduces lumbar lordosis
Example SLR exercise
Requires forceful contraction of the abdominals
If someone has exaggerated lumbar lordosis, their abs may be really weak, unlikely except for polio patients

Question 25

Closed chain abduction

Answer 25

Support hip abduction occurs as you're raising or hiking iliac crest on the nonsupport hip Lumbar spine bends in the direction opposite of the rotating pelvis

Question 26

Closed chain adduction

Answer 26

Support hip adduction occurs as you lower iliac crest on the nonsupport hip

Question 27

Closed chain IR | Closed chain ER

Answer 27

Closed chain IR of the support hip occurs as the nonsupport hip rotates forward Closed chain ER of the support hip occurs as the nonsupport hip rotates backward

Question 28

Primary hip flexors

Answer 28

Iliopsoas, sartorius, TFL, rectus femoris, pectineus, adductor longus

Question 29

Secondary hip flexors

Answer 29

Adductor brevis, gracilis, anterior fibers of glut minimis

Question 30

In the abducted position the iliopsoas can assist in

Answer 30

External rotation

Question 31

Rectus femoris is responsible for

Answer 31

1/3 of total isometric flexor torque at the hip

Question 32

The axis of rotation is

Answer 32

Behind the hip joint and anterior to the knee joint normally Osteoarthritis causes anterior tilt so the axis of rotation moves in front of hip and posterior to the knee Changed the way body weight should fall through lower extremity Iliofemoral ligament and psoas major and hamstrings get really short

Question 33

Primary hip adductors

Answer 33

Pectineus, adductor longus, brevis, Magnus, gracilis

Question 34

Secondary hip adductors

Answer 34

Long head biceps femoris, gluteus maximus inferior fibers, quadratus femoris

Question 35

Superficial on cadaver, middle, and deep

Answer 35

Pectineus, AL, gracilis Adductor brevis Adductor Magnus (biggest)

Question 36

Why do soccer and hockey players pull their groin?

Answer 36

Because it is constant stop and go. Muscles are vulnerable here

Question 37

What happens when you kick leg across body (in adduction)

Answer 37

Right leg is open chain adduction, concentric contraction, needs to produce a lot of force Left leg closed chain adduction because right pelvis dropping down, glut med on this side may be eccentrically lengthening to control some of the closed chain adduction that may be happening on opposite pelvis Also adductor Magnus on right side trying to stabilize so we don't get hip flexion

Question 38

Sagittal plane adductors

Answer 38

Regardless of hip position the post fibers of add Magnus are always a potent extensor of the hip, too far posterior

Question 39

Remaining adductors can become

Answer 39

Flexors or extensors depending on position

Question 40

In hip flexion adductor longus In hip extension

Answer 40

Is posterior to the axis of rotation so it becomes a hip extensor Is anterior to the axis of rotation so it becomes a hip flexor

Question 41

Secondary internal rotators of hip

Answer 41

Anterior fibers of gluteus minimis, glut medius, TFL, AL, AB, pectineus, semitendinosis, semimembranosis

Question 42

What happens to secondary internal rotates when hip is flexed 90 degrees

Answer 42

The line of force becomes perpendicular to the axis of rotation which increase torque potential so they become primary internal rotators

Question 43

In an anatomical position most adductors can

Answer 43

Produce modest amount of IR of the hip

Question 44

Linear aspera is

Answer 44

Anterior to the longitudinal axis of rotation, because of this the adductors have the ability to produce IR The more hip flexion the more torque you can produce

Question 45

If you want to strengthen internal rotators

Answer 45

Put hip in flexed position first, especially if they had a bad groin pull) So if you want gluteus minimis to function as hip internal rotators you need to put it in hip flexion

Question 46

Greatest glut medius EMG activity is found

Answer 46

In side lying and internal rotation in the position of a clam shell

Question 47

Primary hip extensors

Answer 47

Glut max, hamstrings, posterior head of adductor Magnus

Question 48

Secondary hip extensors

Answer 48

Posterior fibers glut medius and adductors with hip flexed more than 50 degrees

Question 49

From about 75 degrees of hip flexion adductor Magnus and hamstrings

Answer 49

Produce equal extension torque

Question 50

Primary hip abductors

Answer 50

Glut medius, minimis, TFL

Question 51

Secondary hip abductors

Answer 51

Sartorius, piriformis

Question 52

Which muscle has greater abductor moment arm and largest cross sectional area

Answer 52

Gluteus medius

Question 53

Gluteus medius is broken up into

Answer 53

Anterior fibers: IR/flexion Posterior fibers: ER/extension Middle fibers

Question 54

If you want to strengthen glut medius

Answer 54

Stay away from hip flexion, in hip flexion they will get stronger as IR

Question 55

Why and when are the hip abductors important during gait

Answer 55

During swing phase when the stance side hip abductors keeps the pelvis from dropping (trendelenburg) The quadratus lumborum on the swing phase will concentrically fire to assist

Question 56

Primary hip external rotators

Answer 56

Glut max, sartorius, piriformis, obturator internus, sup/inf gemellus, quadratus femoris

Question 57

Secondary hip external rotators

Answer 57

Post fibers of glut medius, glut minimis, long head biceps femoris, obturator externus

Question 58

Why is the obturator externus secondary

Answer 58

Sine line of force only milimeters posterior from axis of rotation (small MA)