Shoulder/ Axilla Flashcards
What is the superior Appendicular Skeleton?
bones of the upper limb, from the shoulder, arm, forearm, hand, wrist. it articulates at the axial skeleton only at the sternoclavicular joint
Define the shoulder?
Each shoulder contains a pectoral girdle. It begins at base of neck and overlies thorax and back.
define Arm?
Arm (brachium) arm lies between glnohumeral and elbow joints and contains the humerus
Define forearm?
forearm (antebrachium) lies btwn elbow and wrist joints and contains the radius and ulna
Define hand
Hand (Manus) lies distal to the forearm and is divided into wrist (carpus) and pam region and digits. Contains metacarpal and phalange bones.
Define Wrist?1
Carpus- is part of the hand and Contains the carpal bones
Define Pectoral Girdle?
each shoulder contains pectoral girdle, it is an incomplete bony ring made of clavicle and scapula
Describe structure of Clavicle and its medial and lateral borders.
”s” shaped long bone. Medial half of the shaft projects anteriorly and the lateral half projects posteriorly.
Medial Border: large and triangular, articulates with manubrium of sternum at sternoclavicular joint
Lateral Border: Flat, articulates with the acromion of scapula at acromioclavicular joint.
Function of the clavicle
- strut to suspend upper limb at SC joint
- Protects underlying neurovascular elements supplying upper limb
- transmits impacts to axial skeleton
- provides for muscle attachments
What do fracture of the clavicle cause?
Shoulder drop and pts. suppport the sagging limb with the contralateral (opposite) limb
what are the structures of the scapula? Think of what makes the superior, medial, and lateral borders. And the Superior, inferior and lateral angles.
Scapula is large, triangular flat bone overlying 2nd-7th ribs.
-has HEAD which is separated from BODY by NECK..
-has medial, lateral and superior borders, and superior, lateral, and inferior ANGLES
- Suprascapular notch- divot on Superior Border
-Medial Border- parallel to vertebral spinous processes
-Lateral border- ends at head and neck
-superior angle- where superior and medial borders meet
-inferior angle- where medial and lateral borders meet.
Lateral angle- where lateral and superior borders meet, its truncated as the head and neck.
Scapula has many structures explains the ones listed below:
- spine
- root
- spinoglenoid notch
- acromion
- supscapular fossa
- Coracoid process
- glenoid cavity
- spine of scapula- bony strut arising from dorsal scapula. spine divides the posterior scapula into supraspinous and infraspinous fosae
- root- medial end of scapular spine
- Acromion- flat projection (end of scapular spine)
- spinogleonid notch- is concave and is about midway from where the spine detaches from the body of scapula.
- subscapular fossa- the anterior or constal surface and is concave.
- coracoid process- (L=crow’s arch) arch above superior border
- glenoid cavity- articulates with humerus at glenohumeral joint. is a ringlike head. has Supraglenoid and infaglenoid tubercles that lie above and below it.
Function of scapula
Provide muscle attachments
forms the socket of the glenohumeral joint
increase the range of motion of the upper limb
What is the structure of the proximal humerus? include describing the head, anatomical and surgical necks, greater and lesser tubercles, bicipital and spiral grooves, and the deltoid tuberosity.
Humerus is the largest bone of upper limb
-head- ball shaped and articulates with glenoid cavity at glenohumeral jt. Attached to flared METAPHYSIS that narrows to the shaft
- Lesser and greater tubercle- two bony knobs jut from metaphysics lesser is anterior and greater is larger and lateral.
-Anatomical neck- divides the head from metaphysis and its tubercles
-Surgical neck- encircles the metaphysis just distal to the tubercles.
-intertubercular (bicipital) groove- separates the tubercles.
Deltoid tuberosity-large and projects laterally near the middle of the shaft
- Radial (spiral) groove- curves along the posterior surface.
Function of the proximal humerus?
Provides muscle attachments and froms the ball part of the glenohumeral joint
What population is at risk for fracturing their proximal humerus and why?
the elderly due to bone loss and falls
What is the anatomy of the sternoclavicular (SC) joint? Include: type of joint it is, where it is located, what makes it special, and what separtes the joint surfaces.
SC joint is a saddle type of synovial jt between the medial clavicle and the sternal notch of the manubrium.
- it is the only site where the upper limb articulats with the axial skeleton
- an articular disc separates the jt. cavity
- jt surfaces coveres with fibrocartilage.
What are the movements of the SC joint
elevation, depression, protraction, retraction, and rotation.
What ligaments reinforce the joint capsule of the SC joint that supports mostof the weight of the upper limb?
- sternoclavicular
- costoclavicular
- interclavicular
What is the anatomy of the Acromioclavicular joint? (AC)
Include: the type of joint it is, what forms most of the joint capsule?l, what ligaments help resist separation of the joint, and what tee coracoclavicular ligament is divided into (parts)?
- AC joint is a planar type of synovial joint with an articular disc
- the acromioclavicular ligament forms most of the joint capsule.
- strong Coracoclavicular and coracoacromial ligaments resis separation of the joint and coordinate movements between clavicle and scapula.
- divided into CONOID (L=cone) and TRAPEZOID (L = 4 sided) parts
Movements of the AC joint?
Gliding and rotation
What type of joint is the glenohumeral joint?
Where is it located?
What are its movements?
- Synovial joint of ball and socket type
- btwn the head of humerus and glenoid cavity
- abduction, adduction, flexion, extension, medial rotaion, lateral rotation, and circumduction.
what is and forms the glenoid labrum?
the hyaline cartilage forms the glenoid labrum( deepens the small shallow glenoid cavity) and covers the articular surfaces
Why is the joint highly mobile but relatively unstable (glenohumeral jt)?
b/c the humeral head is much larger than the glenoid cavity such that only 1/3 of head is in contact with cavity at a given time
what help reinfor the joint capsule of the glenohumeral joint?
the rotator cuff tendons whcih are external to it. The tendon of the long head of biceps brachia also helps stabilize it
what are the 2 fluid filled bursae that are apart of the glenohumeral joint do and where are they located?
they act as cushions between the joint and adjacent muscles.
1-subacromial (subdeltoid) bursa underlies the acrominon and AC ligament
2- The subscapularis bursa, underlies the subscapularis muscles.
What are the anterior axioappendicular muscles?
4 muscles that attach the anterior axial skeleton to the superior appendicular skeleton. INclude: pectoralis major, pectoralis minor, subclavius and serratus anterior
1-Explain what the pecoralis major looks like 2- its origin 3-its insertion 4- its innervation 5- its actions
1- large fan shaped muscle that covers the anterior chest wall. has clavicular and sternocostal heads
2-clavicular head from medial clavicle; sternocostal head from sternum; and 1-6th costal cartilages and aponeurosis of external abdominal oblique muscle
3-Lateral lip of intertubercular groove (superior fibers insert inferiorly, and inferior fibers insert superiorly)
4-medial and lateral pectoral nerves
5-acting together both head adduct and medially rotate humerus; acting alone clavicular head flexes glenohumeral jt;
sternocostal head-extends (the flexed) glenohumeral jt.
1-whats the pectoralis minor 2-origin? 3-insertion? 4-innervation? 5- Action?
1-small triangular muscle underlying pec major
2-3rd-5th ribs (near costal cartilages)
3-medial pectoral nerve
4-protracts scapula
1- whats subclavius muscle? 2- origin 3-insertion 4-innervation 5-action
1-small, strap like muscle underlying the clavicle 2- 1st rib (near costal cartilage) 3-inferior surface of middle clavicle 4-nerve to subclavius 5-depresses the clavicle
1- whats the serratus anterior muscle? 2- origin 3-insertion 4-innervation 5-action
1-large, saw-toothed muscle overlying lateral thoracic wall
2-lateral surfaces of 1st-8th ribs
3-anterior surface of medial border of scapula
4- long thoracic nerve (of bell)
5-protracts and rotates the scapula
If you injure the long thoracic nerve what can you expect to see?
you will paralyze the serratus anterior and the scapula will move away from the throacic wall causing “winged scapula”
whats the posterior axioappendicular muscles and what muscles is it made up of?
five muscles attaching the posterior axial skelton to the superior appendicular skeleton. muscles include: superficial trapezius, latissiumus dorsi, deeper levator scapulae, rhomboid major, and rhomboid minor
1- Trapezius 2-origin 3-insertion 4-innervation 5-action
1-large flat triangular muscle covering neck and superior trunk
2-superior nuchal line, external occipital protuberance, nucal ligament and spinous processes of C7-T12 vertbrae
3-lateral 1/3 of clavicle, acromion and spine of scapula
4-Accessory nerve (CNXI)
5-Superior fibers elevate, middle fibers retract and inferior fibers depress te scapula. Acting together, superior and inferior fibers rotate glenoid cavity superiorly.
1-Latissimus Dorsi 2-origin 3-insertion 4-innervation 5-action
1- large fan shaped muscel covering lower back
2-T7-T12 verterbral spines, horacolumbar fascia, iliac crest, inferior 3 or 4 ribs (inferior angle of scapula)
3- floor of intertubercular groove
4-thoracodorsal nerve
5-extends, adducts and medially roates humerus
Levator Scapulae 2-origin 3-insertion 4-innervation 5-action
1-straplike muscle traversing the posterior neck
2-transverse processes of C1-C4 vertebrae
3-medial border of scapula, superoir to root of spine
4-dorsal scapular nerve and cervial nerves
5-elevates and rotates scapula to depress glenoid cavity.
Rhomboides major and minor 2-origin 3-insertion 4-innercation 5-action
1-two rhomboid-shaped muscles, often not distinct from one another
2-minor- from nuchal ligament and C7-T1 vertebral spins; major- T2-T5 VERTEBRAL spines
3-minor- medial broder of scapula at root of spine;
major- medial border of scapula inferior to root of spine
4-dorsal scapular nerve
5-retract and roate scapula to depress glenoid cavity
What are and what muscles make up the scapulohumeral muscles?
6 muscles that attche the scapula and humerus. include: deltoid, supraspinatus, infraspinatus, teres minor, teres major, and subscapularis
1-deltioid 2-origin 3-insertion 4-innervation 5-action
1- muscle shaped the greek letter delta. divided into anterior, middle, and posterior fibers
2-lateral 1/3 of clavicle, acromion and scapular spine
3-deltoid tuberosity
4-axillary nerve
5-anterior fibers flex and medially rotate humers. Middle fibers adduct humerus. post fibers extend and laterally roatate humerus
1-supraspinatus 2-origin 3-insertion 4-innervation 5-action
1- small fan shaped muscle of posterior scapula
2-supraspinous fossa of scapula
2-superior acet of greater tubercle of humerus
4-suprascapular nerve
5-abducate (first 15 degrees) of humerus.
- full abduction of upper limb requires rotation of scapula by TRAPEZIUS
1-infraspinatus 2-origin 3-insertion 4-innervation 5-action
1-small fan shaped muscle of posterior scapula
2- infraspinous fossa of scapula
3-middle facet of greater tubercle of humerus
4- suprascapular nerve
5- laterally rotates humerus
Teres Minor 2-origin 3-insertion 4-innervation 5-actions
1-Small round muscle of the posterior scapula
2-middle part of laterl border of scapula
3-inferior facet of greater tubercle of humerus
4-axillary nerve
5-laterlly rotates humerus
Teres Major 2-origin 3-insertion 4-innervation 5-action
1-thick, round muscle of posterior scapula
2-posterior surface of inferior angle of scapula
3-medial lip of the inter tubercular groove
4-lower sub scapular nerve
5-adducts and medially rotates humerus
1-supscapularis 2-origin 3-insertion 4-innervation 5-action
1-triangular muscle on costal surface of scapula 2-subscapular fossa 3-lessertubercle of humerus 4-upper and lower sub scapular nerves 5- adducts and medially rotates humerus
What is the rotator cuff? and what muscles is it formed by?
- its a musculotendinous ring formed by muscles that attch to the greater and lesser tubercles of humerus.
- tendons bind to reinforce joint capuse and secure humeral head in the glenoid cavity
SITS:
supraspinatus, infraspinatus, teres minor, and subscapularis.
- inferiroly the cuff has no tendons
What is the cuff subject to? and which tendon is the most commonly torn?
subject to calcification, degeneration (esp. due to abduction) and rupture.
Supraspinatus tendon is most commonly torn causing pain in anterosuperior shoulder
what nerve supplies cutaneous innervation of the shoulder skin?
the supraclvicular nerves.
