The Hip Flashcards
What is the hip equivalent to the sternoclavicular joint?
Sacroiliac joint
What movements can occur at the hip
extension flexion abduction addiction lateral and medial rotation
When is the hip joint more relaxed?
When sat down, extended when standing
What is the most powerful muscle in the body?
Gluteus maximus
What is the most powerful group of muscles in the body
quadriceps
what does the ligament of the head of the femur do?
attaches the head of the femur to acetabulum inside the joint keeping the two structures together
What is another name for the ligament of the head of the femur
ligamentum teres
What is the purpose of the fat in the joint?
provides cushioning for thinnest part of acetabulum filling central region
What is the acetabular labrum?
fibrocartilage ring goes round joint and adds suction with synovial fluid
Why is there so much stability in the hip?
deep insertion of femoral head in acetabulum, strong articulate capsule, ligament of head of femur, large powerful muscles, fat pad
What is the role of the rotators?
medial and lateral rotators, medial pull on anterior side and lateral on posterior side of femur into the cup, helps stability
what happens to the rotator fibres when sitting down and standing up
sitting - fibres are horizontal
standing - vertical and twist winding head of femur into cup
What is the purpose of the greater trochanter and where is it
proximal femur, muscle attachment point
What is the acetabulum made up of?
ischium
pubis
ilium
What is the the rim of fibrocartilage?
acetabular labrum
increases acetabular articular surface by 10%
blood vessels pass into joint through notch and in ligamentum teres
What does the pubic symphysis join!
2 hemi pelvises
Where is the articular capsule strongest?
over anterior parts as less muscle here to strengthen it
What is the weakest part of the articular capsule!
posterior as more muscle here like your gluteus maximus
what is the strongest ligament in the articular capsule? what does it do?
anterior iliofemoral joint preventing excessive hip extension
how does the anterior iliofemoral ligament change when sitting and standing?
sitting relaxed
standing taut
What is seen in a dislocated hip
leg is shortened
medially rotated
addicted
hip joint goes posteriorly onto weakest part of capsule (thin articular iliofemoral ligament)
What can happen to the nerves in a hip dislocation
sciatic nerve compressed or stretched by femur head as taken out of acetabulum and end up with nerve palsy
why is the blood supply not really affected by hip dislocation
blood supply is posterior through femoral sheath under Inguinal ligament
What nerve is responsible for hip flexion
femoral nerve
which muscles allow hip flexion
iliopsoas (iliacus and psoas major)
sartorius
pectineus
What does the sartorius do?
hip flexion
hip abduction
lateral rotation of hip
what does pectineus do
addiction and medial rotation of the hip
what is the iliopsoas made up of
iliacus and psoas major
What does the psoas minor do
helps stabilise psoas major in hip flexion
what are the main hip abductors
gluteus medius
gluteus minimus
what is the muscle for lateral rotation
piriformis
Which muscles allow hip flexion
quadriceps
mainly rectus femoris
Which muscles allow hip extension
gluteus maximus
hamstrings assist
what is the gluteus maximus innervated by
inferior gluteal nerve
what are the hamstrings innervated by
tibial division of the sciatic
which muscles allow hip abduction
what innervation
gluteus medius and minumus
superior gluteal nerve
tensor fascia lata - superior gluteal nerve
which muscles allow hip addiction
innervation
medial thigh adductor longus, adductor, adductor Magnus gracious pectineus obturator externus
obturator nerve
which muscles allow hip lateral rotation
gluteus maximus
adductor group
which muscles allow hip medial rotation
gluteus medius/minumus
tensor fascia lata
What is an aponeurosis?
layers of broad flat tendons which have multiple muscles entering it
What is the iliotibial tract
long aponeurosis for tensor fascia lata and superficial and anterior parts of gluteus maximus
What is the role of the iliotibial tract
thickening of deep fascia from ilium to tibia stabilising lateral side of hip and knee, muscles around tightened
how can you get IT band syndrome
iliotibial tract runs over laterofemoral epicondyle and gets irritated from repetitive use
Which sites are femur fractures usually at
high in femoral neck - sub capital
across the neck - cervical
trochanteric region
pretrochanteric
where do older patients normally get fractures in the femur and why
across the neck cervical
osteoporosis so weaker and more brittle
which femur fracture can affect blood supply
trochanteric
what is seen in femur fractures
external rotation and shortened
shentons line disrupted by fracture
what orthopaedic hardware is used for femur fractures
screws
hip replacement
compression plate
What is the main problem as a result of a fracture to the neck of the femu
disruption to blood supply to femoral head and Avascular necrosis
acetabular branch of obturator artery will close in most adults and becomes fibrotic so doesn’t do anything
but
profunda femoris sends off lateral and medial circumflex around femur neck and branches to head and neck of femur, retrograde blood supply
