hip, buttock and thigh Flashcards
hip joint: describe the anatomy and movements of the hip joint; summarise the muscles responsible for these movements, their innervation and attachments; explain the structures responsible for stability of the hip joint; summarise the structures at risk from a fracture of the femoral neck or dislocation of the hip and explain the functional consequences of these injuries
bones of region
pelvis, femur
3 bones of pelvis which contribute to acetabulum (hip joint)
ischium, ilium, pubis
2 layers of fascia in lower limb
superficial (subcutaneous tissue), deep (in thigh, called fascia lata)
where does the fascia lata extend from and down
extends from the pelvis down the leg underneath
the skin like a stocking
what is the thickened area laterally of the fascia lata called
ilio-tibial tract
function of muscles in gluteal region
extensors, abductors, external rotators
3 gluteal muscles (superficial to deep)
gluteus maximus (75% fibres merge with ilio-tibial tract, rest to gluteal tuberosity of femur; extension and adduction), gluteus medius, gluteus minimus (both cross laterally and attach to greater trochantar of femur; abduction), (tensor fasciae latae is neurologically gluteal but functions more like anterior thigh muscle, stabilising knee)
4 short external (lateral) rotators of hip (similar to rotator cuff muscles, so stabilise hip joint as well)
piriformis (anatomical landmark; sacrum to greater trochanter of femur), obturator internus (from obturator foramen), gemellus (superior and inferior), quadratus femoris
what compartment of the thigh is responsible for hip flexion
anterior compartment
what compartment of the thigh is responsible for hip adduction
medial compartment
what compartment of the thigh is responsible for hip extension
posterior (extensor) compartment
what do ligaments in gluteal region do
connect bones and provide passageways for nerves and vessels
what ligaments convert the greater and lesser sciatic notches (parts of ischial bone) to greater and lesser sciatic foramen
sacrotuberous (sacrum to ischial tuberosity) and sacro-spinous (sacrum to ischial spine) ligaments
what does the greater sciatic notch transmit
structures leaving pelvis to lower limb, including sciatic nerve
what does the lesser sciatic notch transmit
structure passing from pelvis to perineum
course of sciatic nerve from pelvis to buttock and thigh
passes through greater sciatic notch to pass from pelvis into inferior medial quadrant of buttock -> passes through buttock (usually inferiorly to piriformis muscle in gluteal region, but sometimes superior) and on posterior aspect of thigh to divide at a very inconstant level
what 2 nerves does the sciatic nerve divide into at knee
tibial nerve and common
peroneal nerve
what does the sciatic nerve supply
posterior (extensor) muscles
what does sciatic nerve divisions supply
all muscles below level of knee
to avoid damage to the sciatic nerve, where are i.m. injections into the buttock administered
superior lateral quadrant (usually gluteus medius)
hip joint type
synovial ball and socket
where is the hip joint
between head of femur and acetabulum (all 3 pelvic bones contribute to this)
what is around the rim of the acetabulum
rim of tissue called acetabular labrum (deepens fossa to increase stability)
what ligament is within the acetabulum
transverse acetabular ligament
where does the capsule of the hip joint extend down
neck of femur, extending further anteriorly than posteriorly
what runs in the capsule of the hip joint
blood supply to head of femur
2 types of hip fractures, and why
intracapsular and extracapsular, to differentiate if capsule blood supply disruption
4 important ligaments at hip joint
ilio-femoral, pubo-femoral, ischio-femoral, ligament of head of femur (attaches to fovea of head of femur); spirally arranged so when extend hip, spiral and draw head towards pelvis to stabilise
what is the blood supply of the hip joint derived from
medial and lateral circumflex arteries, and artery of head of femur (more significant in children)
what fractures easily damage circumflex vessles
intracapsular fractures at proximal femur, leading to avascular necrosis of head (as circumflex so coming distally)
8 muscles causing hip flexion
ilio-psoas, sartorius, tensor fascia lata, rectus femoris (part of quadriceps femoris), adductor longus, adductor brevis, anterior portion of adductor magnus, gracilis
6 muscles causing hip adduction
adductor longus, adductor brevis, adductor magnus, gracilis, pectineus, obturator externus
5 muscles causing hip extension
semitendinosus, semimembranosus, biceps femoris, posterior part of adductor magnus, gluteus maximus
3 muscles causing hip abduction
gluteus medius, gluteus minimus, tensor fascia lata
6 muscles causing hip external rotators
obturator internus, obturator externus, the gamelli, piriformis, quadratus femoris, gluteus maximus
3 muscles causing hip internal rotators
anterior portion of gluteus medius, anterior portion of gluteus minimus, tensor fascia lata
what spinal levels are hip flexors in general supplied by
L2,3
what spinal levels are hip extensors in general supplied by
L4,5
2 major regions of lower limb
gluteal region (part of trunk), free lower limb (thigh, leg and foot)
2 important structures in ischium bone
ischial spine, ischial tuberosity
interior and exterior parts of ilium
fossa interior, ala exterior
describe the Trendelenberg test
abductors of thigh prevent tilting of pelvis when a limb is raised
