tmj, shoulder, brachial plexus Flashcards
what is the TMJ formed by
articulation between the temporal and mandibular bones
TMJ joint type
synovial
condyloid / hinge
diarthrosis
uniaxial
what are the articular surfaces of tmj
convex condyles of mandible
concave mandibular fossa
convex articular eminence of temporal bone
accessory ligaments of TMJ
fibrous joint capsule
med and lat collateral ligaments
temporomandibular
stylomandibular
sphenomandibular
moevemtns of TMJ
protraction / retraction
lateral deviation
depression (open)/ elevation (close)
upper joint =
plane / gliding
lower joint =
hinge / ginglymus
unique feature of TMJ
the disc moves forward as the mouth opens
as the mouth opens, rotation of the mandibular condyles occurs around the lower joint space
followed by translation of the articular disc on the upper joint space down to the articular eminence
muscles of mastecation
masseter
lateral pterygoid (opens jaw)
medial pterygoid
temporalis (strongest)
other muscles
buccinator, SCM, digastric
where is brachial plexus located
shoulder and armpit
formed by lower 4 cranial nerves and first thoracic nerve from spinal cord
what are the cutaneous/sensory branches
lesser occipital
greater auricular
transverse cervical
supraclavicular
what are the muscular/motor branches
ansa cervicalis
phrenic
segmental branches
what order of the 5 divisions
roots, trunks, division, cords, terminal branches
what is a plexus
a network of nerves that intersect and connect
composed of both sensory and motor fibers
cervical plexus
formed by ventral rami of the upper four cervical nerves and part of the 5th cervical nerve from the spinal cord
located deep to SCM
contains sensory and motor nerves
innervates muscles of neck, skin of head, neck and chest
what attaches to coracoid process
pec minor
coracobrachialis
short head of biceps brachii
sternoclavicular type of joint
synovial
diarthrosis
saddle or plane
multiaxial
sternoclavicular joint accessory ligaments
joint capsule
sternoclavicular
costoclavicular
interclavicular
articular disc
movements of sternoclavicular joint
elevation/depression
protraction/retraction
what is the only synovial joint that connects the upper extremity to the axial skeleton
interclavicular
acromioclavicular joint type
synovial
diarthrosis
plane
triaxial
acromioclavicular joint accessory ligaments
fibrous capsule
acromioclavicular ligament
coracoclavicular ligament (trapezoid, conoid)
coracoacromial ligament
movements of acromioclavicular joint
elevation/depression
adduction/abduction
upward/downward rotation
glenohumeral joint type
synovial
ball and socket
diarthrosis
multiaxial
glenohumeral joint accessory ligaments
superior, middle, inferior glenohumeral ligament (prevents anterior dislocation)
coracohumeral
transverse humeral (holds tendon of biceps in intertubercular groove)
glenohumeral joint movements
flexion/extension
adduction/abduction
horizontal adduction/abduction
medial/lateral rotation
circumduction
movements of scapulothoracic joint
sliding
protraction/retraction
elevation/depression
upward/downward rotation of glenoid fossa
functions of scapulothoracic joint (5)
increase shoulder ROM
maintain length-tension relationship with deltoid
provide GH stability
injury prevention through shock absorption
permit elevation of body
3 structures in subacromial space
supraspinatus tendon
long head biceps tendon
subacromial bursa
actions of the pec as a whole
horizontal adduction
medial rotation of humerus
action of subclavius
pulls shoulder forward and downward stabilizes it
O’s and I’s of subclavious
O: first costal cartilage
I: acromial end of clavicle
N:nerve to subclavius
action of the deltoid
abduction of shoulder joint
anterior fibers flex and medially rotate while posterior fibers extend and laterally rotate shoulder joint
what does the deltoid fibers insert into
deltoid tuberosity of humerus
what does the anterior fibers of the deltoid originate
clavicle
where do middle fibers of deltoid originate
acromion
where do posterior fibers originate
spine of scapula
action of supraspinatus
abducts and laterally rotates shoulder joint
stabilize head of humerus in glenoid cavity
O’S and I’s of supraspinatus
O: 2/3 of supraspinatus fossa
I: superior facet of greater tubercle of humerus
what 2 muscles share suprascapular nerve
infra/supraspinatus
what muscles share axillary nerve
teres minor
deltoid
action of infraspinatus
laterally rotate shoulder joint
stabilize head of humerus in glenoid cavity
O’s and I’s of infraspinatus
O: infraspinatus fossa
I: greater tubercle of humerus/shoulder joint capsule
O’s and I’s of teres minor
O: dorsal surface of lateral border of scapula
I: inferior facet of greater tubercle of humerus
action of teres minor
laterally rotates shoulder joint and stabilizes head of humerus
which 3 muscles of rotator cuff laterally rotate shoulder joint
teres minor
supraspinatus
infraspinatus
which muscle of rotator cuff medially rotates shoulder joint
subscapularis
O’s and I’s of subscapularis
O: subscapular fossa of scapula
I: lesser tubercle of humerus
what does the rotator cuff do as a whole
stabilize head of humerus in glenoid cavity
nerve of subscapularis
upper and lower subscapular nerve
action of teres major
medially rotates
adducts / extends shoulder joint
O’s and I’s of teres major
O:inferior angle and lateral border of scapula
I: crest of lesser tubercle of humerus
which muscles insert at lesser tubercle of humerus
teres major
subscapularis
what inserts at inferior facet
teres minor
