Kinesiology: Hip

What ROM degrees are required for normal gait?

30 degrees of hip flexion

10 degrees extension

5 degrees abduction and adduction

5 degrees internal rotation and external rotation

What happens in femoral anteversion?

Angle of torsion is high

The head of the femur is really far forwards/anterior, does not have good contact with acetabulum

A person with anteverted femur will have their femur inwardly rotated and in-toeing to keep femur head in acetabulum

What happens if the center angle is too narrow?

A center edge angle that is too narrow leads to superior dislocation of the femur.

Infants and young children have narrow center edge angles and it increases due to weight bearing

What are the degrees of flextion, extension, abd/add and int/ext rotation to walk with normal gait on level ground?

30 degrees flexion

10 degrees extension

5 degrees abduction and adduction

5 degrees internal rotation and external rotation

What is the function of the hip joint?

Stabilization

The hip joint supports the weight of the head, arms and trunk

○Standing: 100% closed chain

○Walking: 60% closed chain, 40% open chain

What kind of joint is the hip joint?

Synovial diarthrodial joint

How many degrees of freedom does the hip joint have?

3 degrees of freedom: ABD/ADD, ext/flex, int/ext rotation

What are the articular surfaces of the hip joint?

Acetabulum of pelvic bone articulates with femur head

What 3 bones make up the acetabulum?

ilium, ischium, pubis

What is loose packed position for hip joint capsule?

Hip flexion, abduction and external rotation (FABER)

This is also the position that gives the greatest amount of contact between femur and acetabulum

What covers the surface of the acetabulum that actually articulates w head of femur?

hyaline cartilage

T/F Hip extension is the position of best joint contact and closed pack position

False

In hip extension, part of femur head is not in contact w acetabulum, so not the position of optimal contact, just position of stability and hip ligaments are taut.

What covers the head of the femur that articulates w the acetabulum?

hyaline carilage

What deepens the socket and increases the concavity of the acetabulum?

acetabulum labrum

This enhances joint stability by increasing hip joint congruency

What is located in the inferior part of the acetabulum?

transverse acetabular ligament

Helps keep everything together and provides part of the load-bearing surface for the femoral head

What is the fovea capitis?

The fovea capitisis a depression of the femur with no hyaline cartilage

The fovea capitis attaches to the ligamentum teres

What is the center of edge angle? How do we measure it?

The center edge angle is the measure of acetabular depth

Formed by:

A line connecting the lateral rim of the acetabulum and the center of the femoral head

A vertical line from the center of the femoral head

True/False: The center edge angle decreases with age.

False.

Infants and young children have narrow center edge angles and it increases with age due to weight bearing

What plane is the center of edge angle?

Frontal plane measurement

What is the angle of inclination? How is it formed?

Formed by the axis through the femoral head and neck And the longitudinal axis of the femoral shaft

What is the angle of inclination in children? adults?

150 deg in infancy

120 deg in elderly

This change in angle in one's lifetime is due to gravity pushing down on the bone

What is coxa valga? What goes hand in hand with it?

an abnormally high angle of inclination (genu varum may happen) being bow legged

What is angle of torsion? How is it formed?

How much twist is in the bone

In the transverse plane: The axis through the femoral head and neck and the other axis from the lateral to the medial femoral condyles. The angulation between the 2 lines is the angle of torsion

What is coxa varum? What goes hand in hand with it?

an abnormally low angle of inclination (genu valga may happen) being knock-kneed, feet out, knees in

What is the normal angle of torsion in infancy and elderly?

The angle of torsion starts at 40degrees in infancy and end up to 15degrees in adults

Decreases with age

What happens in femoral retroversion? What causes it? What direction will feet go?

Angle of torsion is low

The head of the femur is really far backwards

A person with retroverted hips will have their femur outwardly rotated and their toes faced away from each other

What is located inside hip joint capsule? outside it?

Inside: femoral neck outside: trochanters

What is the closed packed position of the hip joint?

Hip extension in anatomical positon (not full hip extention)

Ligaments are taut in this position

T/F Hip extension, like standing, is a position of stability

True

What position is most likely to dislocate hip?

Flexion, adduction and internal rotation

What hip precautions should someone who had a hip replacement follow?

Don't adduct past neutral

Don't cross legs

Don't internally rotate beyond neutral

Don't flex hip past 90 degrees

What are the 3 ligaments at the hip joint?

Iliofemoral (Y) ligament

Pubofemoral ligament

Ischiofemoral ligament

Which ligaments help prevent hip extension?

All 3 hip ligaments (Y , pubofemoral and ischiofemoral ligaments)

Which ligament helps prevent hip adduction?

Superior part of Iliofemoral or Y lig

T/F: Angle of torsion increases with age

False

The angle of torsion starts at 40deg in infancy and end up to 15deg in the elderly

Which ligament helps prevent hip abduction?

pubofemoral ligament

What is the strongest ligament at the hip?

Iliofemoral (Y) ligament

What are the motions at the hip joint?

Hip flexion Hip extension Hip abduction Hip adduction Hip internal rotation Hip external rotation

What do you need to do to sit crossed legged?

Adduct past neutral

Externally rotate

Flex greater than 90 degrees

In open chain kinematics, which rule (concave or convex) does the femur moving on the acetabulum follow?

Convex rule: convex femur on concave acetabulum

How will the femoral head roll/glide and spin on femoral condyles in open chain kinematics?

Femoral head will glide and spin in opposite direction of femoral condyles

In open chain kinematics, which direction will femoral head and condyle move when in hip flexion?

femoral head spins posteriorly

femoral condyles move anteriorly

What direction does the femoral head and condyles move in open chain hip extension?

Femoral condyles move posteriorly

Femoral head will spin anteriorly

When adducting/abducting or internally/externally rotating the hip in open chain kinematics, which femoral condyle do we look at to determine femoral condyle movement direction?

lateral femoral condyle

In open chain hip abduction/adduction which direction are the femoral head and condyles moving?

Abduction: Head of the femur moves downward

Lateral femoral condyle move upward

Adduction: Head of femur moves upward

Lateral femoral condyle moves down

In which direction do the femoral head and condyles move in open chain hip internal/external rotation?

Internal rotation: femoral head moves posteriorly femoral condyles move anteriorly

External rotation: femoral head moves anteriorly femoral condyles move posteriorly

In closed chain hip kinematics, what moves on what? What rule (concave/conves) rule applies?

Concave acetabulum moving on fixed convex head of femur (concave rule)

In closed chain hip internal rotation, which direction does the acetabulum and opposite side of the pelvis move?

Acetabulum spins ; glides anteriorly.

Opposite side of pelvis moves anteriorly

What direction does the opposite side of the pelvis move compared to acetabulum in closed chain hip kinematics?

Opposite side of the pelvis is going to move in the same direction as the acetabulum

What is active insufficiency?

Active insufficiency is the inability of a muscle, which spans two or more joints, to create enough tension because it is already shortened over BOTH joints simultaneously.

Ex) when you flex your knee and then attempt to extend your hip. Since the hamstring muscles cross both the hip and the knee, when you try to get the leg further behind you (hip extension) with a bent knee (knee flexion), the hamstrings shorten to such a degree that they fail to contract anymore

Ex) If you flex your hip with the knee extended, you won't get as much flexion as you will with the knee flexed: passive insuff of hamstrings active insuff of rectus femoris.

Give an example of active/passive insufficiency of hip flexion.

If you flex your hip with your knee extended, you won't get as much hip flexion as you would with the knee flexed.

Passive insufficiency: hamstrings (stetched btw hip ; knee joint)

Active insufficiency: rectus femoris (cross hip ; knee joint, flexes hip ; extends knee, muscle is contracting ; gets too short

What is passive insufficiency?

Passive insufficiency occurs when the multi-joint muscle is lengthened to its fullest extent at both joints so it can no longer lengthen and allow further movement, but also preventing the full ROM of each joint it crosses. This is generally less likely to be as problematic as active insufficiency

Ex) Full finger flexion cannot be achieved if wrist flexion occurs simultaneously. Maximal hip flexion and maximal knee extension are limited by the lengthening of hamstrings Full knee flexion is limited by the stretching of the Rectus femoris if the hip is fully extended.

Why do we not measure both hips at the same time during bilateral hip flexion?

During bilareral hip flexion, you are also rotating the pelvis/posteriorly tilt pelvis, so you get more degrees of flexion. We never measure both hips at the same time to make sure to measure without the pelvis involved.

How can you get more hip extension?

Get more hip extension when you extend the knee vs when the knee is flexed.

Passive insufficiency of rectus femoris

Active insufficiency of hamstrings (extend hip, flex knee)

What is active/passively insufficient during hip extension with knee extension?

Passive insufficiency of rectus femoris

Active insufficiency of hamstrings

What do you do to sit crossed legged?

Need to be able to adduct past neutral

Externally rotate

Flex greater than 90 degrees

In closed chain hip movements, what moves on what?

pelvis moves on fixed femur

What are motions completed at the hip joint?

Hip flexion Hip extension Hip abduction Hip adduction Hip internal rotation Hip external rotation

In open chain hip movements, what moves on what?

Femur moves on pelvis

True/False In neutral position, ASIS will be in the same plane with the pubic symphysis and at the same level as PSIS

True

Anterior pelvic tilt is the same as ?

doing hip flexion in closed Kinetic chain

What direction does symphysis publis move in anterior pelvic tilt?

downward

What is the lumbosacral angle in anterior pelvic tilt?

More than 30 degrees

In posterior pelvic tilt, PSIS moves ? lumbosacral angle is ?

PSIS moves inferiorly and posteriorly

Lumbosacral angles is less than 30 degrees

What is lateral pelvic tilt referred to as?

Hip hiking and pelvic dropping

Doing hip hiking and pelvic dropping around a pivot point of the weight bearing hip

In lateral pelvic tilt, hip hiking is the same as___ and is done on ___ leg. Pelvic dropping is done on ___ leg and is the same as ___.

In lateral pelvic tilt, hip hiking is the same as hip abduction and is done on weightbearing leg.

Pelvic dropping is done on non-weightbearing leg and is the same as hip adduction.

What is lumbar pelvic rhythm flexion?

Coordinated motion of the hip joint, pelvis and lumbar spine. All work together to produce a greater ROM than if only one segment worked by itself.

When you bend over to touch toes, can only flex hips to 90 degrees when knees are straight, but to get fingers closer to ground, can flex lumbar spine to add 45 degrees.

What should you do to hip adbuct to 90 degrees?

Abduct both hips at same time

In Right LE weightbearing: What happens to the pelvis and lumbar spine during hip flexion? hip extension?

Hip flexion: (sagittal plane, both legs on ground)

Pelvic Motion: anterior pelvic tilt

Lumbar Spine Motion: lumbar extension

Hip extension (sagittal plane, both legs on ground) Pelvic Motion: posterior pelvic tilt

Lumbar spine: lumbar flexion

During Right LE weightbearing, hip adduction how does the pelvis and lumbar spine move?

Hip Adduction: pelvic drop, R lateral flexion When pelvis drops, don't want the whole trunk to drop, want to keep trunk upright.

When pelvis drops, get adduction at the weight bearing hip and lumbar spine laterally flexes to right.

During R LE weight bearing and R hip int/ext rotation, what happens to pelvis and lumbar spine?

Hip internal rotation (transverse plane)

Pelvic motion: forward rotation

Lumbar spine: rotation to L

Hip external rotation (transverse plane)

Pelvic motion: backward rotation

Lumber flexion: rotation to R.

In R LE weight bearing, pelvic/hip hike happens on ___side

non-weight bearing side (hip hike left elg).

The weight bearing side is abducting. The lumbar spine is laterally flexing to the left (to continue facing forward).

In Right LE weight bearing, which hip internally rotates while the pelvis comes forward and lumbar spine rotates to the left.

weightbearing side (right) interanlly rotates

In neutral position, the ASIS and PSIS are ?

at the same level/in line of each other ASIS will also be in same plane w pubic sympysis

Hip joint works primarily in ___ chain kinematics.

closed

walking: 60% closed chain

standing: 100% closed chain

When can hip adductors act as hip extensors?

When fully flexed at the hip, part of adductors fall posterior to axis of rotation of flexion/extension of the hip and therefore will have a function in hip extension.

When can hip adductors act as hip flexors?

When hip is fully extended, part of the adductors are in front of the axis of rotation for flexion/extension and therefore will have a function in hip flexion.

Which hip extensor (gluteus maximus or hamstrings) is more efficient and why?

Gluteus Maximus- much longer moment arm = more extensor force= more efficient & effective

What role does the piriformis muscle play in sciatica?

In some people, the sciatic nerve exits the VT column and pierces through the piriformis muscle. If the piriformis muscle spasms, the person will experience sciatic nerve symptoms due to piriformis syndrome

Hip external rotators are analogous to ?

rotator cuff muscles They are joint compressors of the hip joint the same way rotator cuff muscles are compressors of the shoulder joint

What do you rely on to stay standing in anatomical standing?

Iliofemoral (Y) ligament

Line of gravity is posterior to axis of hip flex/ext (posterior to greater trochanter) which sets up an external moment at the hip at sagittal plane = tend to posteriorly tilt pelvis on femur. The external force of the ground reaction force and gravity, will try to extend your hip. So all you need is passive internal force of Y ligament to overcome external extension force- don't need iliopsoas to counteract. You can simply hang on your ligaments at hip joint in quiet anatomic standing- don't need muscle force at hip join= can stand for long periods of time wo tiring.

What would happen if the line of gravity was in front of the hip?

There would be a flexor moment ar the hip and you would need muscle force (hamstrings, glut max) to prevent collapsing forward. This would be alot of work, may end up using back extensor muscles too ex) carrying bag of groceries or pregnant women: recline trunk backward to move line of gravity posteriorly, less muscle work

"If someone has a weak glut medius, what can happen?

Will flex trunk to weight bearing side Or alternatively, exhibit Trendelenburg Sign.

During normal stance both lower limbs bear half of the body weight is some part of stance phase. When one lower limb is lifted in swing phase, the other takes the entire weight. During the stance phase of gait, the pelvis tilts downwards on the weight-bearing extremity and hikes up on the non-weight bearing extremity. But when there is a hip abductor weakness, the pelvis tilts downwards instead of upwards on the non-weight bearing extremity. In an attempt to lessen this effect, the person compensates by lateral tilt of the trunk away from the affected hip, thus center of gravity is mostly on the stance limb causing a reduction of the pelvic drop

What are signs of osteoarthritis?

This joint pain happens with movement and also with weight bearing

o Will have stiffness after rest

o The individual can get crepitation during joint motion When the joint moves back and forth, there's a "snap, crackle, and pop"

o Can also have spasm or atrophy of the muscles around that joint

o Can get decreased ROM

Not because of weakness of the muscle but because of pain

o Can also get malalignment of the extremity

o May have tenderness to palpation

What are indicators for total hip arthroplasty (total hip replacement)?

Failed conservative management

Conservative means anything that is not surgery (i.e. PT and OT)

Difficulty with ADL's

What happens if a person has a weak hip abductor muscle or pain?

Laterally flex trunk to weight bearing side

Drop the pelvis (Trendelenburg sign)

In unilateral stance/weight bearing on one leg, what happens to the line of gravity?

When we are weight bearing on one leg, the line of gravity shifts to the weight bearing hip

Where is the line of gravity in unilateral stance/weight bearing on one leg?

Medial to the weight bearing hip

What happens to the nonweight bearing side of the pelvis during unilateral stance/weight bearing on one leg? What happens in reaction to the non-weight bearing side?

Non-weight bearing side of the pelvis tends to drop down in unilateral stance due to gravity and body weight pulling it down, creating an adductor torque around the hip.

Hip Abductor muscles, gluteus medius and gluteus minimus, will have to work to counteract nonweight bearing hip tendency of falling.

What does the gluteus medius and gluteus minimus do during unilateral stance/weight bearing on one leg?

When the gluteus medius muscle contracts, it pulls the non-weight bearing side of the pelvis up so that the pelvis is level.

Role of gluteus medius during closed kinematic chain is to stabilize the pelvis

For equilibrium to take place, bodyweight times its moment arm must equal the force of gluteus medius times its moment arm

What happens if the gluteus medius is too weak in unilateral stance/weight bearing on one side?

If gluteus medius is too weak to do the job, we will end up with the non-weight bearing side of the pelvis dropping down and hence we end up with a Trendelenburg position/gait. We will also have lateral trunk flexion to weight bearing side.

In asymmetrical standing, the more weight bearing side is ____ to the hip.

adducted

Need to use abductors to bring you over to middle

In asymmetrical standing we are going to need which muscles to return to symmetrical standing?

Abductor and adductor muscles

In asymmetrical standing, the side that has less weight bearing, will need ___ to bring you back to the middle.

Adductors

Side that is not weight bearing Is abducted from hip in asymmetrical standing

What is the job of the gluteus medius in closed kinematic chain?

stabilize the pelvis, not abduct the femur (usually functions as a hip abductor)

Use the gluteus medius to try and keep the pelvis level because gravity wants to pull that side of the pelvis down

How is the gluteus medius similar to the deltoid muscle?

It's fibers on different sides perform different functions Gluteus medius (muscle fiber work similarly to deltoid muscle)

• Fibers on side -Abduct hip

• Anterior fibers- Flex hip, internally rotate hip

• Posterior fibers- Extend hip, Externally rotate hip

In Right lower extremity (R LE) weight bearing, what are sagittal, frontal and transverse plane pelvic motions?

Sagittal plane motions: Anterior & posterior pelvic tilt Frontal plane motions: pelvic drop &hike Transverse plane: forward & backward rotation

In pelvic drop during right lower extremity (R LE) weight bearing, what are the hip joint and lumbar spine motions?

When the pelvis drops, you don't want the whole trunk to drop, want to keep the trunk upright

When the pelvis drops down

• Going to get adduction at the weight bearing hip

• And the lumbar spine is going to laterally flex to the right

In a Right lower extremity (R LE) weight bearing pelvic hike, which side of the hip is hiked? What motion occurs at the lumbar spine and hip?

Hip hike on the non-weight bearing side (hip hike left leg)

• The weight bearing side is now abducting (R hip abduction)

• And laterally flex to the left (to continue facing forward) (L lateral flexion at the spine)

In Right lower extremity (R LE) weight bearing forward pelvic rotation, you will internally rotate at which side? What happens at the lumbar spine?

When the pelvis comes forward

• Internally rotating on the weight bearing side (right)

• Rotating lumbar spine to the left