5: Pelvis and Hip - Mahoney Flashcards Preview

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Flashcards in 5: Pelvis and Hip - Mahoney Deck (36)
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1
Q

2 joints of pelvis

A

symphysis pubis (synchondrosis)

sacroiliac (syndesmosis)

2
Q

3 planes of motion in pelvis

A

SAGITTAL(anterior/posterior tilt)

FRONTAL
left lateral pelvic tilt (left side moves upward)
right lateral pelvic tilt (right side moves upward)

TRANSVERSE
left transverse pelvic tilt (left side moves posterior)
right transverse pelvic tilt (right side moves posterior)

3
Q

angle of inclination of femur in infant and adult

A

Infant-150°
Adult-125°

angle in the FRONTAL plane formed by the axis of the head and neck of the femur and shaft of the femur

4
Q

define coxa vara and coxa valga

A

Coxa vara: a decrease in the angle of inclination so that the distal femur is directed towards the midline and the knees are closer together (genu valgum)

Coxa valga: an increase in the angle of inclination so that the distal femur is directed away from the midline and the knees are farther apart (genu varum)

5
Q

define varus and valgus

A

Varus: the distal end of the distal bone comprising a joint points towards the midline

Valgus: the distal end of the distal bone comprising a joint points away from the midline

6
Q

what is the purpose of the normal inclination angle

A

The inclination angle allows abductors to function with a mechanical advantage as they counterbalance body weight in one-legged stance

Hip abductors should be as far laterally from the hip as possible to achieve muscle stability which is maximum when the child begins to stand

7
Q

what is alsberg’s angle?

A

angle formed by a line through the epiphyseal plate of the neck of the femur and the long axis of the femur

normal = 41 degrees

Increase is coxa valga, decrease is coxa vara

8
Q

angle in the transverse plane formed by the axis of the neck of the femur and the transcondylar axis of the knee with the apex of the angle lateral

A

Angle of Declination of Femur

9
Q

normal angles of declination of femur

A

Infant-30° to 60° of internal rotation (normal internal femoral shaft rotation known as FEMORAL ANTEVERSION)

Adult-8° to 12° of internal rotation

Therefore, angle decreases about 20°-50° by rotating externally, but still remains internally rotated by about 10° in the adult

10
Q

The angle of declination:

  1. is formed by the axis of the neck of the femur and the shaft of the femur
  2. Is internally positioned at birth
  3. Decreases as the child ages
  4. A and B
  5. B and C
A

5

1 = angle of inclination

11
Q

Hip Abductors: Orange Gorillas Go To Pais

A
obdurator internus
gluteus minimus
gluteus medius
tensor fascia lata
piriformis
12
Q

Hip Adductors: Golfers Often Quit After Putting Grimly

A
gluteus maximus
obturator externus
quadratus femoris
adductors
pectineus
gracilis
13
Q

Hip Flexors: Poor Individuals Really Suffer

A

psoas major
iliacus
rectus femoris
sartorius

14
Q

Hip Extensors: Giant Birds Swarm Seattle

A

gluteus maximus
biceps femoris
semimembranosus
semitendinosus

15
Q

Knee Flexors: Some Students Believe Gross Sucks

A
semimembranosus
semitendinosus
biceps femoris
gracilis
sartorius
16
Q

Knee Extensors: Vegas Virgins Very Rare

A

vastus medialis
vastus lateralis
vastus intermedius
rectus femoris

17
Q

External Hip Rotators: Go Out And Get Some Quality Players

A
gluteus maximus
obdurators
adductors
gemelli
sartorius
quadratus femoris
piriformis
18
Q

Internal hip rotators

A

gluteus medius and gluteus minimus

19
Q

normal fetal position

A

like buddha

hips and knees flexed, hips externally rotated, knees and ankles internally rotated.

When the HIP is flexed in utero, it is also externally rotated; When the LOWER LIMB is flexed in utero, it is also internally rotated

This uterine position leads to:

  • an increase in external rotation and flexion of the hip
  • femoral anteversion caused by femoral head and neck rotating towards the anterior shaft of the femur-allows maximal rotation of hip in flexed position
20
Q

_________ is created from the adducted position of the femur

A

angle of inclination

21
Q

While the ______ femur externally rotates (decrease in angle of declination), there is a simultaneous inward rotation of the thigh in the region of the hip in the _____ around the hip (ligaments and muscles that attach into the hip

A

bony
soft tissue

The end result is that the knee is eventually pointed straight ahead in gait

The 8 to 12° of femoral anteversion is balanced by the external rotation of about 10° caused by normal soft tissue contraction at the hip as one progresses from infancy

22
Q

define neutral position

A

Position from which a maximum excursion of the range of motion of the joint, any joint, can occur in either direction

23
Q

what is the neutral position of hip?

A

that position in which the hip is neither externally rotated nor internally rotated

24
Q

Calculating NFP neutral femoral position

A
  • Add the amount of external hip rotation to the amount of internal hip rotation
  • Divide by 2 (in the normal adult hip, for every degree of external rotation, there is one degree of internal rotation: 1:1 relationship)
  • Subtract this value from the maximum amount of external hip rotation
    • Perform this with the hip flexed and hip extended
    • Neutral position of the hip that is internal will have a hip that has more rotation internal than external
    • Opposite for neutral position of the hip that is external which will have more external rotation than internal
25
Q

When the NFP is the ______ with the hip flexed and hip extended, the rotation is due to a twist or torque in the femur, itself

A

same

26
Q

When the NFP is _________ with the hip flexed and hip extended, the rotation is due to a soft tissue contracture, usually in the hip joint itself

A

different

27
Q

A NFP that is internal means that the foot will point _______

A

inwards

A NFP that is external means that the foot will point outwards

28
Q

*** normal hip external and internal rotation values

A

Infants: 60-90° external; 0-30° internal (3:1)

Up to 1 year: 50-60° external; 30° internal (2:1)

4 years to adult: 45° external; 45° internal (1:1)

29
Q

normal hip rotation is performed with the hip flexed (tightens primarily the ischiofemoral ligament) and knee flexed. If shortened or taut, the range of hip motion will …

A

decrease internally (usually), so you have an increase of external hip rotation

and with the hip extended (tightens the iliofemoral, pubocapsular, and ligamentum teres ligaments) and knee flexed. If shortened or taut, the range of hip motion will decrease externally (usually) and will increase internal hip rotation

30
Q

With HF, tighten the ischiofemoral ligament (limits internal rotation or promotes external rotation)

With HE, …

A

tighten the iliofemoral and pubofemoral ligaments (limits external rotation or promotes internal rotation)

31
Q

the NFP is not 0. Why?

A

– >If there is no change in amount of hip rotation with the hip flexed and extended, the cause is bony (a lack of enough external rotation of the femoral shaft or too much external rotation of the femoral shaft).

– > If there is a change with the hip extended and flexed, it is due to tightness of the ischiofemoral ligament (if it is external NFP) or due to tightness of the iliofemoral, pubocapsular or ligamentum teres (if it is internal NFP).

32
Q
The neutral femoral position of the hip with the hip extended is 8° internal.  The neutral femoral position of the hip with the hip flexed is 4° internal.  The most likely cause is:
Tight medial hamstrings
Internal torsion of the femur
External torsion of the femur
Tight ligamentum teres
Tight ischiofemoral ligament
A

tight ligamentum teres

33
Q

what are the normal ranges of motion in the sagittal plane of hip?

A

Hip flexion: at least 120°-130°

Hip extension: 0-20°

34
Q

what are the normal ranges of motion in the frontal plane motion of hip

A

Hip abduction: 40-45°
Hip adduction: 20-25

(2:1) in adult

35
Q

how do you test for a tight medial hamstring?

A

To test for a tight medial hamstring (which leads to an in-toe gait or a patella that tracks medially):

  • with patient supine, flex the hip and knee to 90° and maintain this position
  • externally rotate the lower leg (pointing the toes externally) as you gradually extend the knee
  • medial tightness will be manifested by the examiner unable to achieve 160° of knee extension

Lateral hamstring tightness (leading to an out-toe gait or lateral tracking patella) is tested by internally rotating the lower leg (pointing the toes internally) as you extend the knee

36
Q

Match the correct pairs of normal positions or values:

    • Hip extension 20°, hip flexion 120°
    • Hip adduction 40°, hip abduction 20°
    • Coxa varum, genu valgum
    • Increase in external rotation of hip due to tight hip abductors
A

1 and 3