Shoulder, Arm, and Elbow Flashcards
The bones of the proximal-most region of the appendicular skeleton of the upper limb include the
Clavicle, scapula, and humerus
The only one of the upper limb bones which articulates directly with the axial skeleton
Clavicle
There are three major synovial joints of the shoulder region, and free movement at all three joints is required for the shoulder to have full range of motion. What are the three joints?
- ) Sternoclavicular joint (SC joint)
- ) Acromioclavicular joint (AC joint)
- ) Glenohumeral joint
Articulates medially with the manubrium of the sternum as the SC joint
Clavicle
Articulates laterally with the acromion proccess of the scapula at the AC joint
Clavicle
What are the two clavicular articulations?
- ) medially w/ manubrium of sternum (SC joint)
2. ) Laterally w/ acromion process of scapula (AC joint)
The “ball and socket” glenohumeral joint is formed by the articulation of the
Rounded head of humerus with shallow glenoid fossa of scapula
The sternoclavicular (SC) joint is supported by the
SC ligament, Costoclavicular ligament, Joint capsule, and Subclavius muscle
Ankylosis of the SC joint severely limits
Elevation of the arm
The sternoclavicular joint movements are elevation/depression of the arm during flexion/extension and abduction/adduction movements at the
Glenohumeral joint
The acromioclavicular joint is supported by the
Coracoclavicular ligament and the joint capsule
Dislocated by direct forces such as contact with the ground
-referred to as “shoulder separation”
AC joint
The movements at the AC joint are
Rotation assisting movements of the shoulder
The glenohumeral joint is supported bytthe musculotendinous rotator cuff and the
Glenohumeral ligaments and Glenoid labrum joint capsule
At the glenohumeral joint, range of motion limited by pain is caused by
Bursitis or rotator cuff teninitis
At the Glenohumeral joint, range of motion limited by dislocation is caused by
Excessive abduction, extendion, and lateral rotation movements
The movements at the glenohumeral joint are
Abduction/adduction, flexion/extension, medial/lateral rotation, and circumduction
The joints at the pectoral region generally move at the ame time and are coordinated with movements of the
Scapula
This coordinated movement is referred to as
Scapulohumeral rythm
During elevation of the arm, the scapulohumeral movement occurs in a
2:1 ratio of glenohumeral:scapula, SC, and AC joints
The muscles of the shoulder serve to stabilize the shoulder and act as the prime movers of the scapula and humerus at the
Glenohumeral joint
The primary support for the glenohumeral joint
Rotator cuff muscles
What are the muscles of the rotator cuff?
“SITS”
Supraspinatus, Infraspinatus, Teres Minor, and Subscapularis
Provides superior support of the glenohumeral joint
Supraspinatus
Provides posterior support of the glenohumeral joint
Infraspinatus and Teres Mino
Provides anterior support of the glenohumeral joint
Subscapularis
What are the prime movers responsible for PROTRACTION of the scapula?
Serratus anterior and pectoralis minor
What are the prime movers responsible for RETRACTION of the scapula?
Rhomboids and middle trapezius fibers
What are the prime movers responsible for ELEVATION of the scapula?
Levator scapulae, Rhomboids, and superior trapezius fibers
What are the prime movers responsible for DEPRESSION of the scapula?
Pectoralis minor and inferior trapezius fibers
What are the prime movers responsible for UPWARD ROTATION of the scapula?
Serratus anterior and the superior and inferior trapezius fibers
What are the prime movers responsible for DOWNWARD ROTATION of the scapula?
Levator scapulae and rhomboids
What are the prime movers responsible for FLEXION of the humerus?
Pectoralis major, anterior deltoid fibers, arm muscles, biceps brachii, and coracobrachialis
What are the prime movers responsible for EXTENSION of the humerus?
Posterior deltoid fibers, Latissimus Dorsi, Teres major, and the long head of the triceps brachii
What are the prime movers responsible for ABDUCTION of the humerus?
Deltoid and supraspinatus
What are the prime movers responsible for ADDUCTION of the humerus?
Pectoralis major, Latissimus dorsi, deltoid, and Teres major
What are the prime movers responsible for MEDIAL ROTATION of the humerus?
Pectoralis major, Latissimus Dorsi, Deltoid, Teres major, Anterior deltoid fibers, and Subscapularis
What are the prime movers responsible for LATERAL ROTATION of the humerus?
Posterior deltoid fibers, infraspinatus, and teres minor
Supply the shoulder with blood and anastomose with each other providing collateral circulation to the upper
limb
Branches form axillary artery and subclavian artery
The primary collateral roots are
Suprascapular and dorsal scapular (subclavius) to circumflex scapular (sxillary)
The only bone of the arm, and it articulates proximally with the glenohumeral joint and distally with the bones of the forearm at the elbow joint
Humerus
Fractures of the humerus typically occur proximally at the
Surgical neck, along the spiral groove, and distally at the medial superconylar ridge
Fracture at the surgical neck can result in
Axillary nerve trauma
Fracture along the spiral groove can result in
Radial nerve trauma
Fracture distally at the medial supracondylar ridge can result in
Medial nerve trauma
The distal humerus articulates with the proximal portions of the
Radius and Ulna
Which part of the humerus contacts the head of the radius?
Capitulum
Captured by the trochlear notch of the ulna
Trochlea of humerus
In addition, the radius and ulna articulate with each other at the
Radioulnar joints
What are the supporting structures of the elbow?
Radial and ulnar collateral ligaments and the annulr ligament
At the elbow, what dislocations occur for the
- ) ulna
- ) radius
- ) Dislocates posteriorly
2. ) Dislocates inferiorly
Pain and inflammation at the elbow due to overuse of forearm muscles
Epicondylitis
What movements occur at the elbow?
Flexion and extension
What are the supporting structures of the proximal radioulnar joint?
Radial and ulnar collateral ligaments and the annulr ligament
At the radioulnar joint, what dislocations occur for the
- ) ulna
- ) radius
- ) Dislocates posteriorly
2. ) Dislocates inferiorly
What movements occur at the radioulnar joint?
Pronation and supination
In general, the muscles of the arm occupy the anterior or posterior surfaces of the humerus and are separated, anterior from posterior, by
-creates anterior and posterior arm compartments
Medial and lateral intermuscular septa
The muscles within a given compartment all have the same general function, are innervated by the same nerve and receive their blood supply via branches of the
Same artery
What is the function of the muscles of the anterior arm compartment?
Flexion at glenohumeral and elbow joints
Innervates the muscles of the anterior arm compartment
Musculocutaneous nerve
The muscles of the anterior arm compartment receive their blood supply from the
Brachial artery
The muscles of the posterior arm compartment function in
Extension at the glenohumeral and elbow joints
The muscles of the posterior arm compartment are innervated by the
Radial Nerve
The muscles of the posterior arm compartment receive their blood supply from the
Deep brachial artery
Which arm muscles function in FLEXION at the glenohumeral joint?
Biceps brachii and coracobrachialis
Which arm muscles function in EXTENSION at the glenohumeral joint
Triceps brachii- long head
Which arm muscles function in FLEXION at the elbow?
Biceps Brachii and Brachialis
Which arm muscles function in EXTENSION at the elbow?
Triceps brachii- Long, lateral, and medial heads
Which arm muscles function in SUPINATION at the elbow
Biceps Brachii
This depression on the anterior aspect of the elbow has a number of important neurovascular structures passing through it
Cubital fossa
In the superficial fascia, cubital veins form anastomotic connections between the
-common site of venipuncture
Cephalic and Basilic veins
Deep to the superficial fascia, the cubital fossa is “roofed over” by the
Bicipital aponeurosis
Protects the deeper median nerve and brachial artery
Bicipital aponeurosis
Within the cubital fossa the brachial artery typically divides into its two terminal branches, the
Radial and Ulnar branches
Crosses through the cubital fossa
Radial nerve
Crosses posterior to the medial epicondyle of the humerus
Ulnar nerve
In a fracture of the middle third of the clavicle (most common), what would happen to the
- ) Lateral portion
- ) Medial portion
- ) Would be pulled inferiorly
2. ) Would be displaced superiorly
When the middle third of the clavicle is fractured, the pectoralis major will pull the proximal humerus medially. This may result in an overlap of the fractured clavicular ends. Which portion would be superior?
Medial portion
Shoulder separation occur at the
AC joint
Shoulder dislocations occur at the
Glenohumeral joint
Fluid filled sac that acts like a synovial membrane and lubricates and smooths the motion of highly active joints
Bursa sacs
Deepens the socket to hold the humeral head
-where labral tears occur
Glenoid labrum
A torn rotator cuff is primarily a tear in the
-patients won’t be able to ABduct their arm the 15 degrees required to get the deltoids involved
Supraspinatus tendon
Supraspinatus tendon passes inferior to the
Acromion process
The glenohumeral joint is weakest
-where it gets no rotator cuff support
Inferiorly
In a glenohumeral dislocation, the head of the humerus moves
Inferior and then anterior
The scapulohumeral rythm essentially says that for every three degrees of motion
2 degrees are from glenohumeral joint
1 degree is from scapular movement
In an X-ray, radial tells us what is
Lateral
In an X-ray, ulnar tells us what is
Medial
Common dislocation caused by parents swinging their kids by the arms
Radial dislocation
If the spiral groove is injured, which nerve is in danger?
Radial nerve
