Hip Flashcards
Hip is ——axial joint with ——-degrees of freedom
triaxial
3
flexion/extension
sagittal plane
abduction/adduction
frontal plane
internal/external rotation
transverse plane
what is circumduction motion?
combination of motions occurring in all 3 planes simultaneously
seen in stroke patients
in the case of the hip, circumduction will cause the foot to be moving
in a circular pattern, and the lower ex will be moving in a cone with apex of the cone at the hip
what is the primary function of the hip?
support the weight of the head, arms and trunk in both static and dynamic weight-bearing
what are some other functions of the hip?
- provide a pathway of forces between the pelvis and the lower ex
- functions primarily in a closed kinetic chain system in which the head is considered the fixed point.
hip functions primarily in
Closed-Kinetic Chain system
what is the fixed point in CKC system?
head
hip flexion is an example of
CKC
The forces applied in static stance w/o muscle contraction: Each femoral head bears about —–of the body weight above the hips
1/2
The forces applied in static stance w/o muscle contraction:Each lower extremity is about ——-body weight
1/6
The forces applied in static stance w/o muscle contraction:Each hip bears about ——–of the body weight
1/3
Forces applied to the hip, with muscle contraction:
3X body weight if standing on one leg
Forces applied to the hip, with muscle contraction: stance phase of gait
up to 6 times body weight during stance phase of walking cycle
increase in velocity of gait causes
the increase in force at the hip
The acetabulum faces
laterally
inferiorly
anteriorly
greater trochanter is important for
muscle attachment
neck of the femur is important for
injuries
In an extended position of the hip ( which is a neutral position in sagittal plane)
considerable amount of femoral head is uncovered - not the greatest head coverage
swaddling of the infant puts hip in what position?
Extended
swaddling of infants causes
congenital hip dislocation
swaddling forces the hip into
less congruent position
when the infant is carried on the mother’s hip at a very young age
the incidence of hip dislocation is less than normal
when the infant is carried on the mother’s hip at a very young age
this abducted, flexed, externally rotated position correlates to a position of greater coverage of the femoral head within acetabulum, providing protection to the hip joint
only a ———-shaped portion of the periphery is covered with hyaline cartilage
horseshoe
over time horseshoe shaped cartilage thins and you have direct contact of femoral head with acetabulum fossa and you get
hip arthritis
lack of shock absorbance
lower back pain
the acetabular fossa is
non articular
femoral head ———contact acetabular fossa
DOES NOT
this articular confuguration allows hip joint to have a cushion effect
if the femoral head were in complete contact with the acetabular fossa
then all shock passing up through the femur would then be transferred to the pelvis
now that the femoral head is not in complete contact with the acetabular fossa
the shock is transferred to the articular cartilage which then compresses to help dissipate the shock.
in radiograph if you dont see any joint space that means there is
No cartilage
The entire acetabulum is deepened by
acetabular labrum
The labrum helps
- deepen the socket
- increase relative concavity of acetabulum
hip joint is one of the
most stable joint in the body
hip capsular ligaments
screw down the femoral head into acetabulum as you get into hip extension
As the hip extends the hip capsular ligaments
coil and tighten making hip extension the “closed-packed” position or neutral position
As the hip moves into hyperextension
the ligament act to provide resistance
in hip joint the closed packed or neutral position
is not the position of maximum congruity
what is the most congruent position of the hip
flexed to 90º
abducted
externally rotated
the “quadruped”position
the least stable hip position
flexed
adducted
(there is decreased congruity, and the joint is loose-packed)
what is the strongest ligament of the body?
iliofemoral ligamnet aka the Y ligament of Bigelow
superior fibers of the iliofemoral ligament are
tensed with adduction
Inferior fibers of the iliofemoral ligament are
tensed with abduction
the pubofemoral ligament is taut with
extension
hip abduction
the ischiofemoral ligaments are located
posteriorly
the fibers of ischiofemoral are ———oriented
spirally
the spiral fibers tighten with ————–and loosedn or unwind during———-
hip extension
flexion
Forces passing through bony architecture are often represented by
trabecular patterns
in the hip, the trabecular patterns
the weight bearing forces passing through both femur and pelvis
most of trabecular patterns in the pelvis pass through
acetabulum
There is no significant trabeculae patterns to protect
the neck of the femur …therefore more susceptible to fracture
elderly women tend to get hip fracture
due to osteopenia
The trabeculae act to provide
- reinforcement along weight bearing lines
- prevent the femoral head from being sheared off
An area of increased subchondral bone density exists
in the superior acetabulum
Area of subchondral bone density corresponds to
the area of greatest weight-bearing within the acetabulum
The zone in the hip which has less trabecular reinforcement is called
a zone of weakness
women are more susceptible to hip fracture due to
increased angulations which increases area of weakness
Hip range of motion vary widely in opinions of normal value due to
pelvic tilt
Do we see motions of the femur on pelvis during ckc?
NO
What do we see during CKC motion of the hip?
we see pelvis tilting anteriorly for hip flexion and posteriorly for hip extension
or lateral pelvic tilt in case of abduction and adduction of the hip
Regardless of the direction of the pelvic tilt, in CKC what will occur?
compensation in the lumbar spine
What is Lumbar Pelvic Rhythm?
in OKC, the hip, pelvis and lumbar all work together to provide increased range of motion.
What is normal value for frontal plane hip range of motion?
45º abduction and 45º addction
most people do not seem to have this much range of motion
what is the more realistic value for frontal plane hip range of motion?
30º abduction and 25º adduction
what is the minimum range of motion required for normal daily activities?
20º abduction
Greatest amount of range of motion is in ——plane
Sagittal
Hip flexion with knee extended
70º-90º
limited by hamstrings
Hip flexion with knee flexed
Greater than 120º
limited by bony architecture or by abdominal girth
How do you evaluate Hip range of motion?
put middle finger under lower back all the way to spine to make sure we aren’t getting hip or spine motion.- when you feel pressure, stop lifting the leg
hip hyperextension is limited by
capsular ligaments particularly the iliofemoral ligament
hip extension with the knee extended may be limited by
the medial thigh muscle group
Hip extension with the knee flexed to 90º may be limited
by the quadriceps femoris
Transverse plane hip range of motion varies depending on
the position of the knee and the hip
what is the benefit of measuring hip range of motion with the knee flexed ?
muscle limitations to transverse plane hip motion have been minimized
What is the benefit of measuring hip range of motion with the hip flexed?
ligamentous limitation has been minimized
What are the theoretical normal values for transverse plane hip range of motion?
45º External rotation
45º internal rotation
What is the minimum hip ranges of motion required for normal gait in sagittal plane?
30º flexion
10º hyperextension
What is the minimum hip ranges of motion required for normal gait in frontal plane?
5º abduction/adduction
What is the minimum hip ranges of motion required for normal gait in Transverse plane
5º internal/external rotation
climbing stairs, sitting, crossing legs all increase
hip ranges of motions
during gait, as you go through pre-swing you get
rapid hip flexion
