Blue Boxes Flashcards
Absence of pectoral muscles is uncommon but may occur. Which muscle is typically missing? What disability does this result in?
Sternocostal part of pec major, no disability results
The anterior axillary fold is absent on affected side, and nipple is more inferior than usual
_____ syndrome occurs when both pec major and pec minor are absent, which results in breast _________, and absence of _________ segments
Poland
Hypoplasia
2-4 rib
Paralysis of serratus anterior is caused by injury to the __________ nerve, which is typically protected when the limbs are held at your sides.
What makes this nerve unique?
Long thoracic
Unique bc it courses on superficial aspect of the muscle it innervates - serratus anterior, this makes it more vulnerable when the limbs are elevated
Paralysis of serratus anterior d/t injury to the long thoracic nerve results in what symptoms?
Medial border of scapula moves laterally and posteriorly away from thoracic wall = WINGED SCAPULA
When arm is raised, medial border and inferior angle of scapula pull markedly away
Upper limb may not be able to be abducted above horizontal position bc serratus anterior cannot rotate the glenoid superiorly to allow complete abduction [trapezius also helps raise arm above horizontal]
The triangle of auscultation is a small triangular gap near the inferior angle of the scapula. What makes up its 3 borders?
Superior horizontal of latissimus dorsi
Medial border of scapula
Inferolateral border of trapezius
How would you have your patient enlarge their triangle of auscultation in order to better hear their lung sounds?
Have them draw their scapula anteriorly by folding arms across chest with chest flexed
Parts of 6th and 7th ribs and 6th intercostal space will be subcutaneous
What is the primary clinical manifestation of an injury to the spinal accessory nerve?
Marked ipsilateral weakness when shoulders are shrugged against resistance
Thoracodorsal n. typically supplies lat dorsi m., it passes inferiorly along the posterior wall of the axilla and enters the medial surface of the muscle close to where it becomes tendinous.
It is most at risk during what types of procedures?
Surgery in inferior part of axilla
Mastectomies because axillary tail of breast is removed
Surgery on scapular lymph nodes because its terminal part lies anterior to them and the subscapular a.
What is the result of injury to the thoracodorsal n.?
Paralysis of latissimus dorsi –>
Inability to raise the trunk with the upper limbs (climbing)
Person cannot use axillary crutch because shoulder would be pushed superiorly by it, and they cannot initiate active depression of scapula. Passive depression is usually supplied by gravity so normal activities remain unaffected
What does the dorsal scapular nerve supply and what results from injury of this nerve?
Normally supplies rhomboids, so their actions are affected in paralysis
If unilateral rhomboids affected, scapula on affected side is located further from midline
What nerve passes inferior to humeral head and winds around surgical neck of humerus, then runs transversely under the deltoid at the same level?
Axillary n
What nerve is usually damaged during fracture of surgical neck of humerus, dislocation of glenohumeral joint, or compression from crutch use?
Axillary n
Severe damage of axillary n. Results in what?
Deltoid muscle atrophy - the rounded contour of that shoulder will be flattened, produces slight hollow inferior to acromion, reducing ability to have IM injections in that area
May alos lead to loss of sensation over the lateral side of the proximal arm = which is the area supplied by the superior lateral cutaneous nerve, a branch of the axillary n.
What type of injury is caused by a direct blow or indirect injury of a child or adolescents shoulder?
Fracture-dislocation of proximal humeral epiphysis, because the joint capsule of the GH joint, reinforced by tendons of SITS muscles, is stronger than the epiphyseal plate
In severe fractures, the shaft of the humerus is markedly displaced, but the humeral head retains normal relationship with the glenoid cavity
What muscle is most commonly ruptured in injuries to the rotator cuff?
Supraspinatous
Rotator cuff injuries result in instability of the ______ joint
________ ________ of the rotator cuff is common, especially in older people
Glenohumeral
Degenerative tendonitis
Arterial anastomoses around the scapula supply networks on the anterior and posterior side. What are the 3 major arteries that make up this anastomosis?
Dorsal scapular a.
Suprascapular a.
Subscapular a.
Collateral circulation with the scapular arterial anastomosis is important in the case of lacerated subclavian or axillary aa. Where would the axillary a. need to be ligated? Why?
Between 1st rib and subscapular a. because potential collateral pathways exist around the shoulder joint proximally and elbow distally.
If the artery is ligated between the origins of the subscapular a. and profunda brachii a., blood supply will be cut off to the arm
Vascular stenosis may result from atherosclerotic lesion in the axillary a., leading to reduced blood flow. What changes occur in the scapular anastomosis in this case?
Blood flow in subscapular a. is reversed, this way blood flow can reach the 3rd part of the axillar a.
What is the difference between slow and sudden occlusion in the axillary a.?
Slow occlusion due to disease or trauma allows time for sufficient collateral circulation to develop and ischemia is prevented
Sudden occlusion does not allow time for this and ischemia may develop in the arm, forearm, and hand
The subscapular a. receives blood through several anastomoses with what 3 arteries?
Suprascapular a.
Dorsal scapular a.
Intercostal aa.
The ________ artery is normally palpated in the inferior part of the lateral wall of the axilla. Compression of this artery against the ________ may be necessary during profuse bleeding.
If compression is required at a more proximal site, it can be compressed at its origin by exerting downward pressure between the clavicle and inferior attachment of the _______ muscle
Axillary
Humerus
Sternocleidomastoid
Describe an aneurysm of the axillary a.
First part may enlarge and compress trunks of brachial plexus leading to pain and anesthesia in areas of skin supplied by affected nerves
May occur in baseball pitchers and football QBs due to rapid and forceful arm movements
What vein is often implicated in wounds to axilla due to large size and exposed position?
Axillary v
When the arm is fully abducted, the axillary vein overlaps the axillary artery ________
Anteriorly
A wound in what part of the axillary vein is most dangerous? Why?
Proximal part, because of risk of profuse bleeding and risk of air entering and producing emboli in the blood
A common clinical procedure is a subclavian vein puncture in order to place a catheter there. Because the needle is advanced medially to enter the vein as it crosses the rib, the vein actually punctured is the terminal part of the _____ vein.
However, the needle tip proceeds into the lumen of the subclavian vein almost immediately. Thus, it is clinically significant that the ____ vein lies anterior and inferior to its corresponding artery
Axillary; axillary
An infection in the upper limb can cause the axillary nodes to enlarge and become tender and inflamed, a condition called _______
The _____ group of nodes is usually the first to be involved.
Enlargement of the ____ nodes may also occur, which may obstruct the cephalic vein superior to the pectoralis minor
Lymphangitis
Humeral
Axillary