Clinical notes Flashcards
The strong costoclavicular ligament firmly holds the
medial end of the clavicle to the 1st costal cartilage
the reason why dislocation of the sternoclavicular joint takes place occasionally
because of the presence of the strong costoclavicular ligament firmly holds the medial end of the clavicle to the 1st costal cartilage
results in the medial end of the c icle projecting forward beneath the skin; it may also be pulled upward
Anterior dislocation
Anterior dislocation
medial end of the clavicle may also be pulled upward by the
sternocleidomastoid muscle.
This dislocation follows direct trauma applied to the front of the joint that drives the clavicle backward
Posterior dislocation
why is the posterior dislocation of the sternoclavicular joint more serious
because the displaced clavicle may press on the trachea, the esophagus, and major blood vessels in the root of the neck
if this ligament ruptures completely, it is difficult to maintain the normal position of the clavicle once reduction has been accomplished
(easily redislocates)
costoclavicular ligament
The plane of the articular surfaces of the acromioclavicular joint passes_______
downward and medially
The strength of the acromioclavicular joint depends on the
strong coracoclavicular ligament
The plane of the articular surfaces of the acromioclavicular joint passes downward and medially so that there is a tendency for the lateral end of the clavicle to
ride up over the upper surface of the acromion
binds the coracoid process to the undersurface of the lateral part of the clavicle
strong coracoclavicular ligament
greater part of the weight of the upper limb is transmitted to the clavicle through this ligament, and rotary movements of the scapula occur at this important ligament
strong coracoclavicular ligament
A severe blow on the point of the shoulder, as is incurred during blocking or tackling in football or any severe fall, can result in the
acromion being thrust beneath the lateral end of the clavicle, tearing the coracoclavicular ligament.
tearing the coracoclavicular ligament due to trauma This condition is known as
shoulder separation
shoulder separation
The displaced outer end of the clavicle is easily palpable. As in the case of the sternoclavicular joint, the dislocation is easily reduced, but withdrawal of support results in
immediate redislocation
what factors contribute to the instability of the shoulder joint
The shallowness of the glenoid fossa of the scapula and the lack of support provided by weak ligaments
strength of the shoulder joint depends on the
tone of the short muscles (subscapularis in front, the supraspinatus above, and the infraspinatus and teres minor behind)
what forms the rotator cuff
tendons of the short muscles that bind the upper end of the humerus to the scapule anterior - subscrapularis superior- supraspinatus posterior - infraspinatus, teres minor no muscular support inferiorly
least supported part of the joint
inferior location, where it is unprotected by muscles.
is the most commonly dislocated large joint
shoulder joint
Sudden violence applied to the humerus with the joint fully abducted tilts the humeral head downward onto the inferior weak part of the capsule, which tears, and the humeral head comes to lie inferior to the glenoid fossa
Anterior Inferior Dislocation
Anterior Inferior Dislocation
The strong flexors and adductors of the shoulder joint now usually pull the humeral head forward and upward into the
subcoracoid position
what muscles will pull the head of the humerus forward and upward into the subcoracoid position
in an Anterior Inferior Dislocation
strong flexors and adductors of the shoulder joint
quadrangular space boundaries
superior - subscapularis, capsule of the shoulder joint
inferior - teres major m.
medial - long head of triceps
lateral - surgical neck of humerus
what are the contents of the quadrangular space
axillary nerve
posterior circumflex humeral vessels
Posterior dislocations are rare and are usually caused by
direct violence to the front of the joint
this landmark is important in identifying posterior shoulder dislocation
greater tuberosity of the humerus, which will no longer bulge laterally beneath the deltoid muscle
- rounded appearance of the shoulder
this type of displacement of the head of the humerus into the quadrangular space can cause damage to the axillary nerve
subglenoid displacement
subglenoid displacement of the head of the humerus into the quadrangular space can cause
damage to the axillary nerve, as indicated by paralysis of the deltoid muscle and loss of skin sensation over the lower half of the deltoid
this nerve can be damaged by downward displacement of humerus
radial nerve and axillary nerve
The synovial membrane, capsule, and ligaments of the shoulder joint are innervated by the
axillary nerve and the suprascapular nerve
the shoulder joint is
sensitive to pain, pressure, excessive traction, and distention
The muscles surrounding the shoulder joint undergo reflex spasm in response to pain originating in the joint, which in turn leads to
immobilize the joint and thus reduce the pain, and atrophy (disuse)
Injury to the shoulder joint is followed by
pain, limitation of movement, and muscle atrophy owing to disuse.
what other diseases can cause shoulder pain
diseases of the spinal cord and vertebral column and the pressure of a cervical rib can cause shoulder pain
Irritation of the diaphragmatic pleura or peritoneum can produce referred pain via the phrenic and supraclavicular nerves
dermatome - lateral margin of the upper lim
C3-6
dermatome - middle finger
C7 dermatome
dermatome - medial margin of the limb
C8, T1, and T2
skin over the point of the shoulder and halfway down the lateral surface of the deltoid muscle
supraclavicular nerves (C3 and 4)
C3 and 4
Pain may be referred to this region as a result of inflammatory lesions involving the
diaphragmatic pleura or peritoneum
s vicular nerves (C3 and 4). Pain may be referred to this region as a result of inflammatory lesions involving the diaphragmatic pleura or peritoneum. The afferent stimuli reach the spinal cord via the
phrenic nerves (C3, 4, and 5)
The superficial veins are clinically important and are used for
venipuncture, transfusion, and cardiac catheterization.
in this condition, the superficial veins are not always visible
state of shock
The cephalic vein lies fairly constantly in the superficial fascia, immediately posterior to the
styloid process of the radius
cubital fossa
vein present
median cubital vein
In the cubital fossa, the median cubital vein is separated from the underlying brachial artery by the
bicipital aponeurosis
This is important because it protects the artery from the mistaken introduction into its lumen of irritating drugs that should have been injected into the vein
bicipital aponeurosis - separates median cubital vein from the underlying brachial artery
vein in the deltopectoral triangle
cephalic vein
The cephalic vein, in the deltopectoral triangle, frequently communicates with the external jugular vein by
a small vein that crosses in front of the clavicle
can result in rupture of this communicating vein (between cephalic vein and external jugular vein)
Fracture of the clavicle
Fracture of the clavicle can result in rupture of this communicating vein,
with the formation of a large hematoma
In extreme hypovolemic shock, this may inhibit venous blood flow and thus delay the introduction of intravenous blood into the vascular system.
excessive venous tone
are the veins of choice for central venous catheterization
median basilic or basilic veins
why is median basilic or basilic veins are the veins of choice for central venous catheterization
because from the cubital fossa until the basilic vein reaches the axillary vein, the basilic vein increases in diameter and is in direct line with the axillary vein
The valves in the axillary vein may be troublesome for central venous catherization
abduction of the shoulder joint may permit the catheter to move past the obstruction
why is cephalic vein not a good choice for central venous catherization
does not increase in size as it ascends the arm
divides into small branches as it lies within the d topectoral triangle
usually cephalic vein joins the axillary vein at a right angle (difficult to maneuver the catheter around this angle)
Infection of the lymph vessels
lymphangitis
Infection of the lymph vessels (lymphangitis) of the arm
frequency
common
Lymphangitis
characteristic of the condition
Red streaks along the course of the lymph vessels
The lymph vessels from the thumb and index finger and the lateral part of the hand follow this vein
cephalic vein
The lymph vessels from the thumb and index finger and the lateral part of the hand follow the cephalic vein to the
infraclavicular group of axillary nodes
those from the middle, ring, and little fingers and from the medial part of the hand follow this vein
basilic vein
those from the middle, ring, and little fingers and from the medial part of the hand follow the basilic vein to the
supratrochlear node
supratrochlear node
location
lies in the superficial fascia just above the medial epicondyle of the humerus
the supratrochlear node follows to the
lateral group of axillary nodes
Once the infection reaches the lymph nodes, they become enlarged and tender, a condition known as
lymphadenitis
lymph vessels from fingers and palm
direction of flow
fingers and palm
dorsum of the hand
forearm
what is the complication that can happen after infection of the fingers or palm.
inflammatory edema, or even abscess formation, which may occur on the dorsum of the hand (because of the pathyway of the lymph vessels from fingers and palm
The tendon of the long head of biceps is attached to this structure within the shoulder joint
supraglenoid tubercle
Advanced osteoarthritic changes in the shoulder joint can lead to erosion and fraying of the tendon (long head of triceps) by
osteophytic outgrowths, and rupture of the tendon can occur.
Fractures of the head of the radius can occur from falls on the
outstretched hand
As the force is transmitted along the radius, the head of the radius is driven sharply against the
capitulum
which leads to
splitting or splintering the head
Fractures of the neck of the radius occur in this population
young children
Fractures of the neck of the radius occur in young children from falls on the
outstretched hand
proximal fragment of the radius is supinated by the
supinator and the biceps brachii muscles
The distal fragment of the radius is pronated and pulled medially by the
pronator quadratus muscle
how are the fragments of the radius pulled
proximal - supinated
distal - pronated and pulled medially
The strength of these muscles shorten and angulate the forearm
brachioradialis and extensor carpi radialis longus and brevis
In fractures of the ulna, the ulna angulates
posteriorly
To restore the normal movements of pronation and supination of the radius and ulna, this must be done
normal anatomic relationship of the radius, ulna, and interosseous membrane must be regained
fracture of one forearm bone may be associated with
dislocation of the other bone (but not all the time)
shaft of the ulna is fractured by a force applied from behind.
Monteggia’s fracture
the position of bones in Monteggia’s fracture
bowing forward of the ulnar shaft and an anterior d location of the radial head with rupture of the anular ligament
the proximal third of the radius is fractured and the distal end of the ulna is dislocated at the distal radioulnar joint.
Galeazzi’s fracture
Fractures of the olecranon process can result from a fall on
flexed elbow or from a direct blow.
this muscle is inserted on the olecranon process
triceps muscle
Depending on the location of the fracture line of the olecranon process, the bony fragment may be displaced by the pull of this muscle
triceps muscle
Avulsion fractures of part of the olecranon process can be produced by the pull of the
triceps muscle
Good functional return after an olecranon fracture depends on the
accurate anatomic reduction of the fragment
fracture of the distal end of the radius resulting from a fall on the outstretched hand
Colles’ fracture
fracture of the distal end of the radius and occurs from a fall on the back of the hand
smith’s fracture
Colles’ fracture
population usually affected
occurs in patients older than 50 years
Colles’ fracture
position of fragments
force drives the d tal fragment posteriorly and superiorly, and the distal articular surface is inclined posteriorly
This posterior displacement (Colles’ fracture)produces a posterior bump, sometimes referred to as the
dinner-fork deformity
why is it called dinner-fork deformity
because the forearm and wrist resemble the shape of that eating utensil
Failure to restore the distal articular surface (Colles’ fracture) to its normal position will severely limit the range of _____ of the wrist joint.
flexion
It is a reversed Colles’ fracture because the distal fragment is displaced anteriorly
Smith’s fracture
is present over the olecranon process of the ulna, and repeated trauma often produces
A small subcutaneous bursa
A small subcutaneous bursa is present over the olecranon process of the ulna, and repeated trauma often produces
chronic bursitis
Fracture of the scaphoid bone is common in what population
young adults
Fracture of the scaphoid bone is common in young adults; unless treated effectively, the fragments will result to
not unite; permanent weakness and pain of the wrist,
subsequent development of osteoarthritis
Scaphoid bone
The fracture line usually goes through the
narrowest part of the scaphoid (bathed in synovial fluid)
blood supply
of the scaphoid
pathway
blood vessels to the scaphoid enter its proximal and distal ends, although the blood supply is occasionally confined to its distal end
if blood supply is confined to the distal end of the scaphoid bone and a fracture occurs
avascular necrosis risk
fracture deprives the proximal fragment of its a rial supply, and this fragment undergoes avascular necrosis
Deep tenderness in the anatomic snuffbox after a fall on the outstretched hand in a young adult makes one suspicious of a
fractured scaphoid
occasionally occurs in young adults who fall on the outstretched hand in a way that causes hyperextension of the wrist joint.
Dislocation of the lunate bone
Dislocation of the lunate bone
what nerve is commonly involved
median nerve
can occur as a result of direct violence, such as the clenched fist striking a hard object
Fractures of the metacarpal bones
Fractures of the metacarpal bones
angulates
always angulates dorsally
commonly produces an oblique fracture of the neck of the fifth and sometimes the fourth metacarpal bones.
boxer’s fracture
position of the displacement in the fractures of the metacarpal bones (boxer’s fracture)
The distal fragment is commonly displaced proximally, thus shortening the finger posteriorly
is a fracture of the base of the metacarpal of the thumb caused when violence is applied along the long axis of the thumb or the thumb is forcefully abducted.
Bennett’s fracture
Bennett’s fracture
position of the fracture
The fracture is oblique and enters the carpometacarpal joint of the thumb, causing joint instability.
The forearm is enclosed in a sheath of deep fascia, which is attached to the periosteum of the posterior subcutaneous border of the
ulna
what divides the forearm into several compartments, each having its own muscles, nerves, and blood supply
fascial sheath, together with the interosseous membrane and fibrous intermuscular septa
why is it very easy for compression of BV to occur in the forearm
There is very little room within each compartment, and any edema can cause secondary vascular compression of the blood vessels
in secondary vascular compression of the blood vessels which vessels are first affected
veins then arteries
this is a common cause of secondary vascular compression of the blood vessels in the forearm
soft tissue injury
early signs of secondary vascular compression of the blood vessels
altered skin sensation (caused by ischemia of the sensory nerves passing through the compartment), pain disproportionate to any injury (caused by pressure on nerves within the compartment), pain on passive stretching of muscles that pass through the compartment (caused by muscle ischemia), tenderness of the skin over the compartment (a late sign caused by edema), and absence of capillary refill in the nail beds (caused by pressure on the arteries within the compartment)
when diagnosis of compartment syndrome of the forearm is made
tx
deep fascia must be incised surgically to decompress the affected compartment
a delay in tx of compartment syndrome of how many hours will cause irreversible damage to the muscles
4 hours
is a contracture of the m cles of the forearm that commonly follows fractures of the distal end of the humerus or fractures of the radius and ulna.
Volkmann’s ischemic contracture