Deltoscapular Region and Posterior Arm UE1 Flashcards
clavicle
- suspends the scapula and UE
- allows the scapula to move on the thoracic wall
- transmits shock from the UE to the axial skeleton
~ one of the most breakable bones
scapula
- posterior surface has a spine
- anterior (costal) surface has sub-scapular fossa
- spine, acromion and coracoid processes are sites for muscle attachment
- glenoid cavity (point of articulation for humoral head)
motions of the scapula
- elevation
- depression
- protraction (abduction)
- retraction (adduction)
- upward rotation
- downward rotation
when an action takes place at the arm where is it occurring?
glenohumeral joint
when an action takes place at the forearm where it occurring?
elbow joint
when an action takes place at the wrist (extend the wrist) where is it occurring?
radiocarpal joint
how do we define movement at a joint?
- a muscle must cross a joint to exert a
movement at that joint - the orientation of the muscle fibers
relative to its attachments produces
movement - sometimes, a muscle can exert different
movements based on differences in
orientation of the muscle fibers and thus
the axis about which it acts - sometimes, a muscle can cross two joints
long thoracic nerve innervates?
serratus anterior
medial pectoral and lateral pectoral nerve innervate the?
pectoralis major
medial pectoral nerve innervates the?
pectoralis minor
winged scapula
- paralysis of the serratus anterior
- the medial border of the scapula moves
away from the thoracic wall - the UE won’t be able to elevate normally
above the horizontal position - serratus anterior is unable to upwardly rotate
the scapula
deltoscapular region
- Deltoid
- Supraspinatus
- Infraspinatus
- Teres minor
- Teres major
- Subscapulari
deltoid
- has 3 parts (anterior, middle, posterior)
- the parts of the deltoid can act separately
or as a whole
-when all 3 parts of the deltoid contract
simultaneously, the arm is abducted.
teres major
- posterior aspect of the pectoral (shoulder) girdle
- adducts and medially rotates the arm
rotator cuff
- Supraspinatus
- Infraspinatus
- Teres minor and
- Subscapularis muscles
~ (SITS) - SITS tendons reinforce the joint capsule of the
glenohumeral joint - tonic contraction of the SITS muscles hold the
large head of the humerus in the glenoid
cavity
suprascapular artery
- travels over the transverse scapular ligament
- supplies the supra and infraspinatus muscles
suprascapular nerve
- travels under the transverse scapular ligament
- supplies the supra and infraspinatus muscles
- arises from the upper trunk of the brachial plexus-more to
comes on this
axillary nerve and injury
- branch of posterior cord of the brachial plexus
~the deltoid and teres minor atrophy - the axillary nerve winds around the surgical neck of the humerus-susceptible to injury during fracture
~ sensory loss may occur over the lateral arm
quadrangular space
- borders: long head of triceps, teres major and
minor and humerus - Contents: axillary nerve and posterior circumflex
humeral artery
triangular space
- borders: teres major and minor and long head of triceps
-contents: circumflex scapular artery
rotator cuff injury
- most common tendon injury seen and treated
- pathophysiology:
~ frequency increases with age-degenerative and progressive
~other causes include trauma, and occupations
requiring significant overhead activity
~ pain and difficulty with overhead activity, lifting or carrying heavy objects.
~ degree of injury spans tendinopathy, partial tears, and complete tear
~ acute tears happen in younger patients, and
degenerative tears occur in older patients
scapular anastomosis
- interconnection between 2 vessels
~ functions to serve as a collateral flow of blood in case an occlusion should occur in one vessel
what nerve supplies the muscle of the posterior arm and forearm?
radial nerve
what artery supplies the posterior arm?
profunda brachii (deep brachial a)
triangular interval borders
- superior: teres major
- lateral: lateral head of the triceps triceps
- medial: long head of the triceps