Kinesiology Quiz 3

what is hip and thigh primarily responsible for generating

transmission of force

what does knee + leg create?

stability

what do the ankle and foot do?

mobility and balance

first response to a perturbation

hip main functions

dynamic support - facilitates force + load transmission

stability through osseous components + articulations

allows for mobility bc of joint structure

hip joint deal with what type of load

compressive forces

where does most joint area contact occur

98% during mid-stance phase

20% during swing phase

acetabulofemoral joint ligaments

acetabular labrum, ligamentum teres, transverse acetabular ligament

acetabular labrum

ring of fibrocartilage lining socket creating negative pressure suction vacuum sealing femoral head in

reduces friction + absorbs force

gives you proprioception

ligamentum teres

holds bones together from the inside of joint

main hip ligaments

transverse acetabular, iliofemoral, pubofemoral, ischiofemoral

transverse acetabular ligament

main connection point at inferior portion of the joint

iliofemoral ligament

anterior, connects ilium to femur

resists excessive hip extension + adduction

what is strongest ligament in body?

iliofemoral

pubofemoral ligament

inferior, connects pubis to femur

resists excessive abduction + external rotation + minor hip extension

ischiofemoral ligament

posterior, connects ischium to femur

resists internal rotation + abduction

what type of joint is hip?

ball and socket

why is femur more stable than shoulder?

head of femur sits deeper in acetabulum of pelvis

what is acetabulum formed from?

ilium, ischium, pubis

how many innominate bones?

2

anterior pelvic movement

front of pelvis tips forward, back rises

increases lumbar curve (lordosis)

posterior pelvic tilt

front of pelvis tips backward

flattens lumbar curve (flexion)

lateral tilt

one hip drops lower than than the other

lumbopelvic rhthym

pelvic movement always drags the spine with it

ipsidirectional lumbopelvic rhythm

pelvis and spine move in same direction

anterior pelvic tilt + lumbar flexion (same plane + direction)

stoop lift

contradirectional lumbopelvic rhythm

pelvic and spine move in opposite directions

anterior pelvic tilt + lumbar extension

opposite of stoop lift??

what is the knee classified as?

modified hinge joint

sagittal plane with a little transverse

why is knee injured alot?

sandwiched in between 2 powerful joints

hip generates force + ankle deals with GRF

why is knee inherently unstable?

convex femur meets concave tibia and needs help to stabilize it

4 main ligaments of knee

mcl, lcl, acl, pcl

mcl

medial side, resists varus forces

connected to medial meniscus

often injure both at same time from lateral hit

lcl

lateral side, resists varus stress

not connected to lateral meniscus

acl

connects anterior tibia to posterior femur

acl open chain

resists anterior translation of the tibia

acl closed chain

resists posterior translation of the femur

pcl

connects posterior tibia to anterior femur

pcl open chain

resists posterior translation of tibia

pcl closed chain

resists anterior translation of femur

what is strongest ligament in knee?

pcl is strongest

menisci

2 c shaped cartilage pieces sitting on top of tibial plateau

fill in gap between round + shallow femur/tibia for stability

menisci function

shock absorption + force distribution + lubrication and friction reduction

what is patella bone?

sesamoid bone - sits inside a tendon (quad tendon)

sits in trochlear groove and slides up when extend and down when flex

purpose of patella?

pulls quad tendon away from joint increasing moment arm

quads need less force to extend knee making quads more efficient

what is “true” ankle joint?

talocrural

talocrural function

hinge between tibia, fibula, talus

sagittal plane, dorsi/plantarflexion

subtalar (talocalcaneal) function

sits below talocrural between talus + calcaneus

frontal plane, inversion/eversion

ankle mortise

tibia + fibula form an arch + talus fits into like a peg

shape makes it stable

where is talus wider?

anterior (front)

dorsiflexion mortise

wider part of wedges into mortise = very stable

plantarflexion mortise

narrower part in mortise = less stable, more mobile

more ankle sprains in dorsi or plantar?

plantarflexion bc more vulnerable and less stable

dorsiflexion ROM

15 degrees

plantarflexion ROM

45 degrees

inversion ROM

30 degrees

eversion ROM

18 degrees

why is eversion ROM limited?

lateral malleolus extends further down blocking calcaneus from everting

what are pronation + supination?

triplanar - 3 planes simultaneously

pronation

calcaneal eversion + talar adduction + dorsiflexion

foot + ankle pronation

eversion + abduction + dorsiflexion

supination

calcaneal inversion + talar abduction + plantarflexion

foot + ankle supination

inversion + adduction + plantarflexion

pronation arch

arch collapses, foot flattening out

supination arch

high rigid arch, rolling to outside of foot

excessive pronation

tibia internally rotates causing increased knee valgus

increased ACL tear risk

lateral ankle ligaments

ATFL, CFL, PTFL

atfl

most commonly injured ligament in entire ankle

inversion sprains

medial ankle ligaments

deltoid (4 grouped together)

much stronger than lateral side

inversion more common than eversion sprains

foot sections

rearfoot, midfoot, forefoot

rearfoot

calcaneus + talus

midfoot

remaining tarsal bones

forefoot

metatarsals + phalanges

regions of spine

C7, T12, L5, sacrum, coccyx

lumbar vertebrae

largest vertebrae bc they bear the most weight

spinous process short + thick

lumbar facets

90 deg orientation from horizontal

built for flexion/extension - very little side bending

intervertebral discs

in between each vertebrae

annulus fibrosus

tough fibrous outer ring

nucleus pulposus

jelly-like center acting as shock absorber

herniated disc - nucleus pushes through annulus

pelvis and spine

made of 2 innominate bones connected posteriorly by sacrum

anteriorly by pubic symphysis

ischial tuberosity

origin of hamstrings

why tight hamstrings affect pelvic tilt + lumbar spine

pelvic ligaments

iliolumbar, sacrospinous, sacrotuberous, pubic symphysis

iliolumbar

transverse process of L5 to ilium

connects lowest lumbar vertebra directly to pelvis

sacrospinous

connects sacrum to ischial spine

sacrotuberous

connects spine of ilium to ischial tuberosity

pubic symphysis

connects 2 pubic bones anteriorly via fibrocartilage

female pelvis

wider pelvis, iliac crest broader opening, pubic arch is wider

creates larger Q angle

larger Q angle

greater genu valgum tendency leading to more valgus stress at knee

NOT predictive of ACL injury

ACL injury

neuromuscular control, dynamic stability, core + lower extremity kinetic chain control

ACL situational injuries

deceleration, cutting, or changing directions and landing

dynamic movements where neuromuscular control breaks down

thorax soda can

pressurized - rigid and strong protecting organs + scapula

no pressure - collapses easily

Valsalva maneuver

increased intraabdominal pressure exerting force against anterior surface of spine to stabilize it

consequences of valsalva

effects on thoracoabdominal cavitary pressure

hemodynamics

intracranial pressure

thorax pump handle

ribs more forward + backward

thorax bucket handle

ribs move up + around, down + in

fundamental motions of hip

flex/extend, abd/adduct, ext/int rotation

frontal plane forces

adductors + abductors

lateral - abduction + ext rotation

medial - adduction + int rotation

sagittal plane forces

extensors + flexors

anterior - flexion + int rotation

posterior - extension + ext rotation

transverse plane forces

internal + external rotators

iliopsoas muscle

“true groin” muscle

groin muscles or?

adductor muscles

only adductor that cross the knee

gracilis

IT band

not a true muscle - doesn’t do lift leg or anything

big band of CT transmitting force from TFL to knee