shoulder 1 - anatomy Flashcards
shoulder ROM - flexion
150 - 180
shoulder ROM - extension
50 -60
shoulder ROM - abd
150 -180
shoulder ROM - ER
90
shoulder ROM - IR
50 -60
how does the humeral head sit
superior
medial
posteriorly
what is a the shape of the glenoid
projects laterally and anteriorly
SITS of the humeral - what do they do together
they all act to compress the humeral head into the center of the humeral head
the superior facet of the humeral - what is muscle
supraspinatus
what does the supraspinatus help with for the humerous and the glenoid
abd, IR
15 - 30
what is on the middle facet
infraspinatus
what is on the inferior facet
teres minor
what is on the lessar tubercle
the subscapularis
what are the glenohumeral ligaments
composed of a superior, middle and inferior ligament
what does the superior glenohumeral lig resist
inf
ant/pot translation
what does the middle glenohumeral lig resist
ant translation and ER
what makes up the inferior glenoidhumeral ligament
anterior band
posterior band
axillary pouch
what movements does the inferior glenoidhumeral ligament resist
inf and ant/post translations
anterior band - ER
posterior band - IR
the acromional clavicular joint - what movement do we see here
axial rotation of the clavical
this can help to adjust the angulation between the scapula and the clavicle
what movement do we see at the sterno-clavicular joint
protraction and retract
elevation and depression
axial rot
what is the function of the scapula
glenoid - serves as a platform for the humeral head
site of muscle attachment - 17
serves to transfer force from the trunk to the UE
what is the normal resting position of the scapula
medial border is almost verticle
abd 6 cm from the spine
tilted anteriorly approximatly 20-deg
5-10 of upward rot
35 IR
what does the resting position of the scapula create
the resting plane
what is scapular humeral rhythm
it is the total elvation of the arm
60- scapular thoracic joint
120 - at the gleniod humeral joint
2:1 ratio at teh shoulder
what is the path of the scapular humeral rhythm
first 60 GH dominant
next 60 GH and SC
last 60 scapular upward rotation
what is the ROM for isolated GH rhythm - flexion
120
what is the ROM for isolated GH rhythm - abd
120
what is the ROM for isolated GH rhythm - IR
65
what is the ROM for isolated GH rhythm - ER
90
what happens at the humerus with IR and ER rot
it spins ant and post
what are the normal artho if the GH joint
convex moving on concave
combine rot and translation to keep the humerous centered on the glenoid
what do we scarfice in the GH joint
stablility for mobility
how help to provide more stability at the GH joint
the labrum
art cart
artho of - flexion
ant superior roll
posteior inf glide
arthro of - ext
posterior inf roll
ant sup glide
arthro of - abd
sup roll
inf glide
arthro of - add
inf roll
sup glide
arthro of - ER
posterior roll
anterior glide
arthro of - IR
anterior roll
posterior glide
artho of - horizontal abd
posterio lateral roll
ant-med glide
arthro of - horizontal add
ant-med roll
post-lat glide
what is GH motion controlled by
active and passive restraits
and their interaction
what are the passive restraits of the GH joint
bony geo
labrum
capsuloligamentous structures
negative intra articular pressure - the capsule is a close envrioment
what is the labrum
a fibrocartilgounous ring that arrises from the glenoid
it deepend the joint socket
what is the primary attachment site for the GH lig
the labrum
what tendon goes into the labrum
the long head of the biceps
where does the coracohumeral ligament run
from the coracoid to the head of the humerous
what is the transverse ligament in the shoulder region
around the long head of the biceps tendon
when is the coracohumeral ligament taut
abd and inferior translation of the humeral head
restraints to ER - 0 abd
CH lig
SGHL
subscapularis
restraints to ER - 45 abd
MGHL
restraints to ER - 90 abd
anterior band of the IGHL
when is the subscap an effect restraint to ER
when the arm is at its side
it is not effective when the arm is in 90-deg of abd
restraints to IR - 0 abd
posterior band of the IGHL
restraints to IR - 45 abd
ant and posterior band of the IGHL
restraints to IR - 90 abd
ant and posterior band of the IGHL
restraints to inf translation - 0 abd
SGHL
CH-L
restraints to inf translation - 90 abd
IGHL
is there a lot of movement seen at the AC joint
no
what two muscles cover theAC joint
deltoid
upper trap
what are the coracoclavicular lig
conoid (meidal)
trapezoid (lateral)
this is the primary support of the AC joint
what movements are seen at the AC joint
axial rotation (spin)
adjusts the angulation between the scapula and the clavicle
what kind of joint is the SC joint
sellar
what is connecting with the SC joint
clavicle
and
the manubrium of the sternum
what movement do we see at the SC joint
protraction and retraction
elevation and depression
axial rot
what do we expect to see on the dominant hand side of the scapula
depressed
downwardly rotated
anteriorly tilted
what makes the borders of the subacromion space
coracoarcomional lig
acromion
humerus and its ligaments
what are the structures that we find in the subacromional space
long head of the biceps
superior capsule
supraspinatus tendon
upper margins of infraspinatus and subscapularis muscle
subacromial bursa
inf surface of the AC joint
what is the clinical relevance of the subacriomal space
the structures in this area can be impinged with UE movement
what does the elvation of the arm require
ER of the humerus to clear the greater tubercle
upward rot of the scapula to elevate the lateral end of the acromion
what happens if there is a primary impingement of the SA-space
structure stenosis of the SA-space
structural narrowing
what does primary impingement mean
process in which pain in the shoulder is caused mechinical rubbing of the RC tendons by surrounding structures
what happens if there is a secondary impingement of the SA-space
functional stenosis of the SA-space due to irregular arthro
what are the active restraits of the shoulder region - prime movers
deltoid
pect major
lats
teres major
biceps
coracobrachialis
triceps
what are the four muscle of the RC
subscapularis
supraspinatus
infraspinatus
teres minor
what is the primary function of the RC muscle
keep the humeral head in contact with the glenoid
what is the function of the subscapularis
internal rotator
depresses the Humeral head
what is the function of the supraspinatus
abd - first 30-deg
(works with the deltoid)
ER
superior compressor
infra spinatus and teres minor function
ER
posterior compressor
what is the nerve that innervates - subscapularis
suprascapular nerve
what is the nerve that innervates - supraspinatus
suprascapular nerve
what is the nerve that innervates - infraspinatus
suprascapular nerve
what is the nerve that innervates - teres minor
axillary nerve
when does the axillary pouch or the IGHL engadge
90-deg
what nerve wraps around the neck of the humerous
the axillary nerve
rotator cuff interval location
area between the supraspinatus and subscapularis and the base of the coracoid
what is the rotator interval
an area in the shoulder that the RC fails to cover
one of the most common areas for dislocation - 90, 90
what help to reinforce the RI
the long head of the biceps and the coracohumeral ligament
what other area is not covered by the RC
inferiorly
what muscle assists the deltoid with abd
the supraspinatus
what are the three muscles that depress the humeral head
subscapualris
teres minor
infraspinatus
(done during arm elevation)
what is the transverse plane force couple
supcapularis and infraspinatus/teres minor
what does the transverse plane force couple do
they pull the humerus into the glenoid
what is the frontal plane force couple
deltoid
and
inf RC (sub, infra, teres)
what does the frontal plane force couple do
the deltoid raises the arm - pulls the humerus up
the inf RC counteracts the action of the deltoid - inf compressor
what does a distruption of the transverse plane force couple result in
ant or post mirgaration of the umeral head
due to
- weakness
- paralysis
- tear
what does a distruption of the frontal plane force couple result in
superior migration of the humeral head
is the supra in torn are the force couple okay
yes - normal strength and function possible
the essential force couple remain
the larger the tear the greater the dysfunction
posterior cuff tear - force couple distribution
weakness with ER
and little active elevation as possible
subscap tear - force couples distribution
weakness with IR
little active UE elevation
long head of the biceps - general effects on the RC
increase torsional rigity to ER - resistant to the twisting force
long head of the biceps and a slap lesion
this decrease the ability of the tendon to act as a supressor
what is a slap lesion
a superior labral lesion running A-P
what muscles play a role in scapulo-thoracic movement
traps - all
rhomoid
serratus anterior
levator scapule
pect minor
subclavius
action of rhomoid major and minor
Scapular retraction and downward rotation; fix scapula to thoracic wall
Levator Scapulae function
Scapular elevation and downward rotation
lats action
raises the body toward the arms when climbing
shoulder ext, add, IR
upper traps function
scap elevation
middle traps function
scap retraction
lower traps function
scap depression
serratus anterior function
responsible for the anterolateral motion of the scapula, which allows for arm elevation
force couple at the ST joint
serratus ant - inferior angle of the scap ant-laterally
upper traps - pull the scap mediallu
middle and lower traps - stablize during upward rotation
