Download chapter 9 A and P 2017

chapter 9
joints of the body
classification - bony, fibrous, cartilaginous
synovial(diarthrosis)
movement and levers
selected diarthrosis joints
a couple of terms
joint = an area where bones meet
arthrology = study of structure, function, & dysfunction of joints
kinesiology = study of musculoskeletal movement
biomechanics = study of movements, physics, physiology of joints
tendon = tough collagenous CT which joins a muscle to a bone
ligament = tough collagenous CT which joins a bone to a bone
bursa = fibrous sac filled with synovial fluid which protects tissues
articular disc = fibrocartilage which absorbs shock in joints
meniscus = as above but in knees
lots of terms
flexion
abduction
depression
circumduction
lateral(external) rotation
opposition
plantar flexion
excursion
degrees of freedom
extension
adduction
protraction
rotation
supination
reposition
inversion
range of motion
hyperextension
elevation
retraction
medial(internal) rotation
pronation
dorsiflexion
eversion
axis of rotation
more terms
symphysis
effort
monaxial
fossa
epicondyle
calcaneal
fulcrum
multiaxial
condyle
labrum
tuberosity
resistance
biaxial
dens
fovea
malleolus
bony joint = synostosis = immobility
fibrous joint (synarthrosis) = sutures, gomphosis, syndesmosis
sutures
immobile or slightly mobile
serrate (dovetail), lap (miter), plane (butt)
gomphosis = held in place by collagen
syndesmosis = fibrous joint over distance (radius/ulna)
cartilaginous joints (amphiarthrosis)
synchondroses = bones bound by hyaline cartilage
symphysis = bones joined by fibrocartilage
synovial (diarthrosis) = most common & complicated
very mobile to limited mobility
synovial (diarthrosis) joints
most common, most complicated
vary from freely mobile to limited mobility
joints are equivalent to levers
from the point of view of biomechanics
joints act as hammers, screw drivers, wheel barrows,
mechanical advantage
the function of a lever is to provide a benefit
when a force is used to move an object
a wedge allows you to use 80 pounds of force
to push a 400 pound box 6 feet up into a truck
you may use 80 pounds of force
to quickly lift 60 pounds of ice
each type of lever provides an advantage
the benefit may be a reduced effort or increased speed
a mechanical advantage greater than one means
the lever produces more force than was put in
but less speed or distance
a mechanical advantage less than one means
the lever produced less force than was used
but generated more speed or distance moved
body joints allow for many types of movements
and they each have a distinct name
most joints are able to perform two movements
and some can perform more than two movements
the text briefly describes
six synovial joints
but
within the brief description
are many names of muscles, bones,
bony projections, ligaments, bursa, tendons
coordinate what you learn with the lab
you can learn more
but you must learn the ones tested in the lab
TMJ (jaw) joint
the condyle of the mandible interacts
with the mandibular fossa of the temporal bone
held in place by the sphenomandibular & lateral ligament
the joint consists of a depression into the temporal bone
with a synovial membrane, articular disc, and a cavity to
accept the condyle ar the jaw is moved
open your mouth to accept food or …..
yawn or yell ouch or yell awesome
shoulder joint (glenohumeral, humeroscapular)
shallow joint – loose joint – much movement – multiaxial
BUT
stability sacrificed
multiple bony surfaces, ligaments, & tendons
the shoulder is stabilized anteriorly by the biceps brachii muscle
tendon forcing the humeral head into the glenoid cavity
the supraspinatus infraspinatus, teres minor, and subscapularis
muscles stabilize the joint and their tendons form the rotator cuff
five ligaments also stabilize the joint the glenohumeral,
coracohumeral, & transverse humeral
four bursae are present subdeltoid, subacromal, suncoracoid,
and subscapular
elbow joint
hinge – 2 articulations – humeroulnar joint – humeroradial joint
hip (coxal) joint
pelvis – acetabulum – deep socket
very stable – acetabular labrum(fibrocartilage) – fovea capitis
iliofemoral, pubofemoral ligaments anteriorly
ischiofemoral ligament posteriorly
transverse acetabular ligament helps hold
the labrum in place
knee (tibiofemoral)joint
largest – most complex – hinge + gliding + rotation – the joint
capsule involves the lateral & posterior aspects of the knee –
main stabilization is by the quadriceps tendon in front and the
semimembranosus tendon at the rear
two C shaped cartilages the lateral and medial menisci joined
by a transverse ligament absorbs shock
posteriorly (popliteal) extracapsular and intracapsular ligaments
extra = fibular(lateral) & tibial(medial) collateral ligaments
intra = X – anterior & posterior cruciate ligaments (attach to tibia)
13 bursae = 4 anterior = superficial infrapatellar, suprapatellar,
prepatellar, deep infrapatellar – 2 posterior = semimembranous and
popliteal bursa – and 7 on the lateral and medial surfaces
the patella
patella & patellar ligament form patellofemoral joint
ankle (talocrural) joint
two articulations – tibia and talus (medial)
– fibula and talus (lateral)
many ligaments – many bones