Shoulder Anatomy Flashcards
Shoulder abduction (muscles, inn.)
supraspinatus: C5-6, upper trunk, suprascapular n.
originates atop the spine of the scapula (SUPRA-SPINE), inserts onto greater tuberosity
1st 15 degrees abduction
deltoid: C5-6, upper trunk, posterior cord, axillary n.
originates on clavicle, acromion, spine of scapula; inserts onto humerus
remaining ROM shoulder abduction
has 3 heads: anterior (shoulder flexion), middle (abduction), posterior (extension)remaining ROM
Shoulder adduction (muscles, inn.)
pectoralis major: C5-T1 (all roots), all 3 trunks, medial and lateral cords, medial and lateral pectoral n.
shoulder adduction, shoulder flexion
good site for botox injections
latissimus dorsi: C6-8, all 3 trunks, posterior cord, thoracodorsal n.
shoulder adduction/extension/internal rotation
teres major: C6, posterior cord, lower subscapular n.
shoulder adduction/extension/internal rotation
lats and teres major do same thing: adduct and internally rotate
Shoulder flexion (muscles, inn.)
anterior deltoid: C5-6, upper trunk, posterior cord, axillary n.
biceps brachii: C5-6, upper trunk, lateral cord, musculcutaneous n.
short head - coracoid process
long head - supraglenoid cavity
pec major: C5-T1 (all roots), all 3 trunks, medial and lateral cords, medial and lateral pectoral n.
Shoulder extension
triceps: C6-8, all trunks, posterior cord, radial n.
long (posterior) head (mostly attaches to infraglenoid tuberosity)
(v. long head of bicepes goes to supraglenoid tuberosity)
rear deltoid: C5-6, upper trunk, posteroir cord, axillary n.
latissimus dorsi: C6-8, all 3 trunks, posterior cord, thoracodorsal n.
shoulder adduction/extension/internal rotation
teres major: C6, posterior cord, lower subscapular n.
lats and teres major do same thing: adduct and internally rotate
shoulder adduction/extension/internal rotation
Shoulder internal rotation (muscles, inn.)
subscapularis: C5-6, posterior cord, upper and lower subscapular n.
latissimus dorsi: C6-8, all 3 trunks, posterior cord, thoracodorsal n.
shoulder adduction/extension/internal rotation
teres major: C6, posterior cord, lower subscapular n.
lats and teres major do same thing: adduct and internally rotate
shoulder adduction/extension/internal rotation
Shoulder external rotation (muscles, inn.)
*Infraspinatus
C5-6, upper trunke, suprascapular n.
*Teres minor
C5-6, upper trunk, posterior cord, axillary n.
Rear deltoid
C5-6, upper trunk, posterior cord, axillary n.
Glenohumeral arthritis - Dx XRAY findings, Tx
wear and tear over time p/w pain w movement and palpation
joint space narrowing
osteophytes
cortical irrefularities
AC joint arthritis - Dx
AC, CC ligaments hold joint together
wear and tear over time
*SCARF test* crunches joint together
XR: loss of joint space (narrowing), cortical irregularities, fluid/inflammation
AC joint separation (VERY HIGH YIELD)
usually d/t trauma (FOOSH- causes any fracture in UE)
tear AC ligament
CC ligament 2nd to tear
Types 1-6
Grades of AC joint separation (HIGH YIELD)
1: partial AC tear, intact CC - rehab
2: complete AC tear, partial CC tear - rehab
3: complete AC and CC tears - clavicle floats UPWARD - consider surgery
4: complete tears - clavicle floats up and BACK - NEED surgery
5: complete tears - clavicle floats SUPER up and back - NEED surgery
6: complete tears, clavicle floats DOWN - NEED surgery
type 3 and beyond: AC/CC completely torn
types 4-6 definitely need surgery
Clavicle fracture
middle third fractures
Dx: exam/XR
pinpoint tenderness
Anytime fracture - include joints above and below injured bone
Tx: reduce fracture, immobilize in sling 3-6 wks, gradual ROM/PT
If open fracture or very displaced, needs surgery
Proximal humerus fractures - 4 part classification system
1 part: humerus in one part, non displaced impaction
2 part: one part is displaced from the remainder of the humerus
3 part: two fragments are displaced
4 part: four fragments exist
parts 2-4 requires surgery
parts: greater tuberosity, lesser tuberosity, humeral head, humeral shaft
most fractures occur at the surgical neck
Humeral fractures nerve damage
Proximal humeral fractures (surgical neck) - axillary n.
Midshaft fractures - radial n.
Humeral stress fracture
repetetive overuse (pitchers, throwers)
growth plate may be damaged in kids
otherwise stress fractures form at humeral shaft
Sxs: shoulder pain worse with throwing
Dx: TTP over fracture, pain w resisted movement, XR/MRI
Tx: rest 8-12 wks, gradual return to play
Shoulder dislocations
mobility inversely related to stability
- *Instability**: humeral head moves around in glenoid fossa
- *Subluxation**: humeral head pops out of glenoid but immediately returns
- *Dislocation**: pops out and stays there –> usually anterior inferior
usually happens in position of abduction and external rotation (throwing)
same position as anterior apprehension test to check shoulder instability
MC dislocation in adults (v elbow w kids)
posterior dislocations rare
TUBS and AMBRI - treating shoulder dislocations
dislocations 2/2 trauma v laxity treated differently
TUBS
traumatic
unidirectional/unilateral
Bankart lesions coexist
Survery
AMBRI
atraumatic
multidirectional instability (ligamentous laxity)
bilateral
rehab rehab rehab
inferior capsular shift if requires surgery
Bankart and Hill-Sachs lesions (HIGH YIELD)
both associated with anterior dislocations
Bankart:
anterior labral tear - so dislocation likely to happen anteriorly
Hill-Sachs:
posterolateral humeral head compression fx
notch on XR
Labral tear
injured by repetetive overhead activity
Dx: Obrien’s test, XR, MR arthrogram
Adhesive capsulitis
shoulder dormant (not being abdducted) and capsule becomes restricted and tight
usually s/p trauma, stroke, inflammation
starts w restricted abduction/ext rot
painful for several months - stiff for several months - may gradually improve as “thaws” out
Tx: PT, GHJ steroid injection and subAC space (only treats pain), suprascapular n. block + high vol lidocaine + steroid + saline into GHJ, OR to break up contracture, arthroscopic surgery
Rotator cuff tear
SItS - supraspinatus, infraspinatus, teres minor, subscapularis
supraspinatus usually torn (hurts w abduction)
also hurts w overhead activities and sleeping on arm (ischemia)
partial tears - rehab; if too painful try steroid+lidocaine injection
compelte tears - surgery
consider regenerative therapy (PRP, increasing popularity for tendon tears)
Dx: empty can, full can, drop arm, neer, hawkins (supraspinatus); ext rot, belly lift off (subscap)
XR- high riding humerus, MRI best, US quick in office
Scapular dyskinesis
abnormal motion of scapula causing back and shoulder pain
d/t periscapular muscle weakness: serratus anterior, trapezius, rhomboid, levator scapul, pec minor
Dx: scapular winging
- medial: serratus anterior weak, long thoracic n. injury
- lateral: trapzeius weak, spinal accessory n. injury
Biceps tendonopathy
usually at proximal long head tendon
long head: inserts supraglenoid tuberosity
short head: inserts coracoid process
d/t repetetive biceps loading and shoulder overuse
tendonopathy: nonspecific pathology
tendonitis: acute (<6 wks) inflammation d/t microtears
tendonosis: chronic (> 6wks) degeneration d/t overuse
Dx: speed, yergason, hook, ludington, MRI/US
Tx: beward biceps tendon rupture w steroid injections
