Shoulder Flashcards
What prevents humorus from sliding out of its pocket (glenoid cavity)
The 4 short muscles,
- subscapularis
- supraspinatos
Posterior
- infraspinatos
- teres minor
ALL converge at the humorus as flat supporting tendons to form a continuous cuff called a rotator cuff
What 2 muscles border the axilla?
Latisimus dorsi & pectoralis major
Where do the veins and arteries travel in relative to the scalene muscle
Veins run in from of the anterior scalene while arteries run behind it
Describe the different names that vessels change into in order, do their structures change as well?
Subclavian» axillary» brachial
No
Cephalic vein arises from which vein?
Axillary vein
Basilic vein arises from what veins?
Brachial vein
What r the divisions of the posterior cord of the brachial plexus?
Radial, (the centre one) and axillary
The axillary nerve arise from which nerve?
Posterior cord
Where does the axillary start?
At the lateral border of the first rib
When dies brachial artery end
At the elbow joint
What r stabilizers of the glenohumarol joint?
Rotator cuff muscles
Which ligaments limit upwards movement of the humerus?
The coraco-acromial arch!
-acromiom
-caracoid process
Caraco acrmial ligament
What is the benifit in the axillary recess of the joint capsule?
It sags down, amd this fold provides a reserve capacity useful durimg ABDUCTION mkvemnts of the arm.
joints of shoulder (3 true) (2 functional articulations
Sternoclavivular joint
Acromioclavicular joint
Glenohumarl joint
Subacromial space
Scapulothoracic joint
What forms the rotator cuff?
SITS
supraspinatos
Infraspinatos
Teres minor
Subscapularis
What is the first bone to ossify?
Clavicle
Which nerve is mostly likely to be damaged in a mid-shaft humeral fracture. why?
Radial, bc it runs in the radial groove on the POSTERIOR surf of the shaft
Which muscles r responsible for abduction if the arm from 0-15 degrees? 15-90? 90-180?
Supraspinatus
Deltoid
Trapezius/ serratus anterior
What muscle does axillary nerve innervate?
Deltoid & teres minor
What innervates serrtaus muscle?
Long thoracic nerve (c5,6,7)
Pectoralis minor insertion and orginin
“Pectoralis minyyyy» ribs 5, 4 &3!
Corocoid process
Which shoulder joint is th emost commonly doslocated joint?
Glenohumeral joint
What stabilzes the glenohumeral joint?
Joint capsule, glenohumeral ligaments, glenoid labrum,negative intra-acular pressure,extracapsular ligamenets
What r the muscle stabilzers of the shoulder joint
-rotator cuff
-biceps brachi
-
Where is the bursa on the shoulder joint located? What is its function
Subacromion bursa, reduces friction btw tendon of the supraspinatous and acromion.
Which direction of shoulder dislocation is the msot common?
Anteriorly.
Which nerve is most likely to be damaged in a genohmrol dislocation
Axiallry artery.
In treatment of anterior shoulder dislocation, how do u know the patients shoulder is back again
If the patient can touch the opposite shoulder
What could be a common cause of shoulder dislocation in elderly?
A tear in the roatator cuff muscles
Examples of anterior shoulder dislocation in athletes
Rugby, when someone oushe u too hard from in front
When do posterior discloations usually occur?
In what position would the patient typically hold his arm?
Results from forceful contractions of the roator cuffs In seizures and electric shocks
- Patients present with arm internally rotated and adducted.
What is the function of the corocoacromial arch?
Stabilise humeral head in glenoid cavity (chna shade) & limits upward movement of of humerus
Which parts of the brachial plexus lie underneath the clavical?
Divisions
Where in the brachial plexus does the radial nerve arise from?
Posterior cord
What nerves arise from the posterior cord of the brachial plexus?
- radial nerve
- axillary nerve
- upper and lower subscapular nerve
- thoracodorsal nerve
Where in the clavicle do most clavicular fractures occur?
Middle third
What anatomical structure is bound to the anatomical neck of the humerus?
Joint capsule
What is calcific supraspinatos tendonitis? In what case can this lead to ‘subacromial impingment? How many weeks does it take to resolve?
Calcium hydroxyapitite deposits in the rotator cuff.
if person abducts the arm, it can impinge on it and cause pain»_space; if it bursts, u get ACUTE CALCIFIC TENDONITIS!
-1-2 wks
what is Osteoarthrisits?
what happens during rheumatoid arthritis?
erosion of articular cartilage.
-synovial membrane that lubricates and protects the joints r inflamed,
pain and swelling follows
What is the pectoral girdle (shoulder girdle)
is the set of bones which connects the arm to the axial skeleton on each side. In humans it consists of the clavicle and scapula; in those species with three bones in the shoulder, it consists of the clavicle, scapula, and coracoid
During a clavicular fracture, what pull the medial portion of clavicle up?
Sternocleidomastoid
** POSTERIOR DISLOCATION IS EASILY MISSED ON A XRAY,
just saying ;p
What type of pain do u get in impingment?
How do u treat it?
Low painful arc
What is the main reason the glenohumeral joint is so u stable?
The humeral head is disproportionately larger than the glenoid cavity
why would there be a poor wrist and finger extension if radial nerve is damaged?
injury to the radial nerve would cause paralysis in the brachioradialis and all extensor muscles of wrist and fingers
a patient comes in with her radial nerve damaged, how will u expect the position of her wrist to be?
wrist drop, unable to extend the wrist.
What anatomical feature of the shoulder joint makes the humeral head relatively prone to dislocation?
The glenoid fossa (cavity) is shallow.
joint is weakly strengthened on its INFERIOR aspect.
What is the most common direction of dislocation and why? In what position would the patient typically hold his arm?
- head of the humerus dislocates inferiorly, but displaces in an ANTERIOR due to the pull of the muscles
- The arm would be externally rotated and slightly abducted.
What complications may occur after anterior dislocation of the shoulder?
- axillary nerve damage
- brachial plexus damge
- axillary artery damage
- recurrent shoulder dislocation (again -.-)
- bankart lesion
- hillsachs lesion
- rotator cuff injury
what is a bankart lesion? hill sachs lesion? what r these complication of?
avulsion in the Anterior (inferior) glenoid labrum of the shoulder
hills»a dent at the back of the humeral head (postrolateral)
Anterior shoulder dislocations
function of red bone marrow and erythropoietin? where & when is it produced? give an example in CHD where EPO is produced in high levels
red bone marrow produces RBC’s ( eythropeosis)
Kidney produce epo when o2 levels r low.
epo> stimulate RBC production
What is a joint?
A joint or articulation or arthrosis is a point of contact
- between neighbouring bones, -between cartilage and bones,
- between teeth and bones.
What are the three main components of all synovial joints?
- Articular surfaces covered by hyaline cartilage, separated by joint cavity
- Synovial membrane (lining cavity) that secretes synovial fluid
- Protective capsule surrounds joints.
what is the significance of giving the hormone ‘relaxin’ to pregnant women
it relaxes her pelvic joints at the end of pregnancy
how does aging effect the joints?
- synovial fluid prodcution decreases
- thinning of articular cartilage
- shortening of ligaments & decreased flexibility
What are the six movements of the scapula? Which are the principal muscles that produce each movement?
Protraction – Serratus anterior
Retraction – Middle fibres of trapezius; rhomboids
Elevation – Upper fibres of trapezius; levator scapulae
Depression – Gravity and lower fibres of trapezius
Lateral rotation/upward rotation – upper and middle fibres of trapezius Medial rotation/downward rotation – Latissimus dorsi, levator scapulae, rhomboids
how do u treat glenohumeral osteoarthritis?
- analgesia and excretes
- steroid injection
- joint replacement
how can u treat a tear in the rotator cuff? in what age group is this more common in?
cuff is not repairable, perform reverse anatomy replacement.
which tendon from the 2 biceps runs along the inter tubercular groove?
long head of biceps brachii
u ask a patient to slowly abduct their arm, from approximately 90 degrees, the limb suddenly drops to the side in an uncontrolled manner. what could be the problem?
the supraspinatous tendon is torn.
What is ‘painful arc’? in what cases may this pain be present?
pain on abduction of the arm from a 60-120 degrees. movement will be restricted in this area.
-a disorder in the subacromial space» ex: calcific supraspinatous tendonitis, subacromial bursitis
What type of joint is the acromioclavicular joint?
Plane joint
What type of joimt is not a synovial joint?
Gomphoisis ( its a fibrous joint)
Where is the ‘anatomical neck’ of the humerus? What anatomical structure is attached to it? What is its significance in a child?
articular capsule of the shoulder joint.
-marks the region of the epiphyseal growth plate during the growth in length of the humerus.
In a proximal clavicular fracture, auscultation of the chest must be performed and a chest X-ray may also be needed. What rare but important complication needs to be excluded?
Pneumothorax due to proximity of apex of lung to middle third of clavicle
