Exam 2 - hip arthrology Flashcards
describe the ligamentum teres
tubular
synovial-lined connective tissue housing acetabular artery
contains mechanoreceptors
how does the transverse acetabular ligament run
inferior portion of acetabulum
what is the acetabulum
deep, cuplike socket
place that femur attaches
describe the acetabular fossa
floor to fossa
no cartilage
no contact
filled with fat, blood vessels, synovial membrane, ligament
the femoral head normally contacts only along the ____ surface
lunate
what cartilage covers the acetabulum
where is it the thickest, why
articulate cartilage
articular cartilage is thickest along the superior anterior region as this is the highest joint force with walking
forces __% swing to ___% body weight (BW) at midstance
13%, 300%
during midstance, how does the acetabulum conform for walking
nitch widens
lunate deforms
increases contact area/decrease pressure
the stance phase is between _% and __% contact of the gate cycle
0%, 60%
the swing phase is between __% and ___% contact of the gate cycle
60%, 100%
the area of the joint contact increases from ~__% of the lunate surface during swing phase to about 98% during mid stance phase
20%
describe the acetabular labrum
what is its function
strong
flexible ring of fibrocartilage rim of the acetabulum
poor vascularized, well innervated
provides mechanical stability grip and deepens the socket
how does the transverse acetabular ligament run
spans the acetabular notch
what is the labro-chondral junction
internal labrum blends with articular cartilage of acetabulum
what is dysplastic acetabulum
malformed
does not fully cover the femoral head
chronic dislocation/OA/pain
how do you measure dysplastic acetabulum
center-edge (CE) - degree acetabulum covers femoral head
what is acetabular anteversion angle
extent to which the femur faces anteriorly
20 degrees
what is femoral version (ante/retro)
angular difference between axis of femoral neck and transcondylar axis of the knee
craigs test
what is acetabular anteversion
measurement used on cross-sectional imaging especially pelvic CT for the assessment of acetabular morphology
what is femoral torsion
what is the normal range
relative rotation between the bone’s shaft and neck
15 degrees
what is considered excessive anteversion
what is retroversion
> 15 degrees excessive anteversion
< 15 degrees retroversion
___ degrees anteversion in infants
40 degrees anteversion in infants
derotates to 25 degrees as child ages to 16 y.o.
what can occur with excessive anteversion
hip dislocates/OS/increase contact stress
in-toeing
what is the function of the illiofemoral/pubofemoral/ischiofemoral ligaments
reinforce external capsule, iliocapsularis, gluteus minimus, rectus femoris
what is the function of the iliofemoral ligament
thick
strong, upside down Y medial and lateral
AIIS/rim of acetabulum to intertrochanteric line
elongated by full hip extension and full external rotation
what is the function of the pubofemoral ligament
taught in hip abd/ext and some ER
what is the function of the ischiofemoral ligament
posterior
spirals
taught in IR and abd
describe the iliocapsularis muscle
deep hip flexor
lateral to iliacus
origiantes from inferior fascet of the AIIS
attachment onto anterior hip joint capsule
when are the iliofemoral ligaments stretched
what is the significance of the stretch
when the pelvis is posterior to the hip joints
stretch provides passive flexion torque at the hip, helps to balance the extension torque generated by gravity
what position has the max joint congruity for the hip
90 degrees flexion, moderate abd and ER
what are the oesteokinematics of hip motion
femoral on pelvic: femur about a fixed pelvis
pelvic on femoral: rotation of the pelvis over fixed femurs
describe the femoral on pelvic in the sagittal plane
hip flexion: 120-140 degrees
pelvic tilt
lumbar flexion
with lE extended: 70-80 degrees
hip extension: 18-30 degrees
describe the femoral on the pelvic in the frontal plane
abduction: 40-55 degrees limited by pubofemoral and adductor muscle
adduction: 20-25 degrees limited by abd/piriformis/ITB
describe the femoral on pelvic in transverse plane
IR: 30-45 degrees
ER: 32-50 degrees
describe the femoral on pelvic in transverse plane
IR: 30-45 degrees
ER: 32-50 degrees
what are the 2 types of lumbopelvic rhythm
ipsidirectional, contradirectional
describe the ipsidirectional pelvic on femoral motion
lumbar spine and pelvic move in same direction
maximizes angular displacement of entire trunk
describe the contradirectional pelvic on femoral motion
lumbar spine and pelvis move in opposite direction
supralumbar can stay nearly stationary
used in walking where head and eyes need to be still
lumbar spine is decoupled
what occurs in the sagittal plane furing pelvic rotation in the contradirectional lumbopelvic rhythm
hip flexion/anterior tilt/lumbar spine extension
hip extension/posterior tilt/spine flexion
what occurs in the frontal plane during pelvic rotation in contradirectional lumbopelvic rhythm
abduction of supported hip (standing)/opposite iliac crest hikes/opposite side spine lateral flexion
adduction is opposite
describe the arthrokinematics of hip flexion
roll anterior, slide posterior and inferior
describe the arthrokinematics of hip extension
roll posterior, slide anterior and superior
describe the arthrokinematics of internal rotation of the hip
roll anterior, slide posterior
describe the arthrokinematics of external rotation of the hip
roll posterior and slide anterior
escribe the arthrokinematics of hip abduction
roll superior and slide inferior
describe the arthrokinematics of hip adduction
roll inferior and slide superior
describe the arthrokinematics of hip adduction
roll inferior and slide superior
during NWB hip abduction:
convex/concave or concave/convex
convex on concave
during NWB hip abduction:
convex/concave or concave/convex
concave on convex
