Card Set Information
what is the continuation of the brachial artery supplying the forearm?
Median a. (after common interosseous a.)
what is the continuation of the median artery to the digits?
what is the main blood supply to the digits (thoracic limb)?
list the main blood vessels supplying the thoracic limb.
axillary, brachial, median, and digital aa.
how much clinical application does knowledge of the vascular supply of the digits have in carnivores?
little if any (shively)
into what parts can the venous system of the forelimb be divided?
deep and superficial veins
where are the deep veins and how are they named?
parallel arteries and assume same name
what are the locations of the cephalic and accessory cephalic veins of the manus; where do they join and continue as the cephalic vein?
cephalic palmar paw; accessory cephalic dorsal paw; meet above carpus
what connects the cephalic vein to the brachial vein? where?
median cubital vein; cranial to the elbow
what main thoracic limb veins return blood towards the heart?
cephalic and axillary vv
what are the lymph nodes of the thoracic limb?
axillary (not palpable), accessory axillary (inconsistant, palpable if present), superficial cervical (palpable)
Where is the axillary lymph node located?
in axilla, caudal to axillary vv.
what is the brachial plexus?
ventral branches of the last few cervical and first one or two thoracic spinal nerves
what two muscles does the suprascapular nerve innervate?
supraspinatus and infraspinatus mm
what bone does the suprascapular nerve cross?
cranial surface of the scapular neck
the named nerves of the limbs mainly carry what type of fibers?
sensory and motor fibers (ventral brs.)
what is the function of the cutaneous nerves?
carry sensory input from the skin to the central nervous system
what is an area of skin innervated by only one nerve?
what is the area of skin supplied by only one nerve?
autonomous zone (AZ) or dermatome
what nerves, that don't arise from the brachial plexus, innervate the skin of the caudolateral aspect of the arm?
what nerve innervates the extensors of the elbow and is, thus, necessary for weight bearing?
what is the mnemonic for remembering where the nerves come off the brachial plexus?
MAR:middle (musculocutaneous, axillary, radial)
MU:caudal (median, ulnar)
what two nerves innervate the flexor muscles of the forearm?
median and ulnar nn.
what nerve supplies the extensors of the elbow, carpus and digits?
radial n. (extensor nerve)
What is the course of the radial nerve in the forearm?
Deep: into extensor mm. of the digits, superficial branches to the skin of the dorsal forepaw.
where does the radial nerve first reach the skin?
lateral arm, under the border of the lateral triceps
what is autonomous cutaneous distribution of the superficial radial nerve
dorsal paw (manus)
what is the cutaneous innervation of the paw of the ulnar nerve?
abaxial 5th lateral digit
what is the terminal branches of the median nerve?
medial and lateral palmar nn.
list the bones of the proximal row of carpal bones from medial to lateral
radial, ulnar, and accessory carpal bones
what are the two small bones of located at the metacarpophalangeal joints of the four weight bearing digits?
proximal palmar sesamoid bones
where on the thoracic limb do we start using dorsal and palmar?
proximal end of carpus
what is the normal appearance of the head of humerus in a film?
smooth and round, with no flattening
what is the primary site for osteochondrosis in the dog?
caudal aspect of the head of the humerus
how does the subchondral bone appear in OC of the shoulder?
flattening of cratering of caudal head of humerus with subchondral bone sclerosis
what can cause subluxation of the humeral-radial joint?
premature closure of either proximal or distal radial physis
can the distal physes of the forearm normally be palpated in young carnivores?
yes considerably enlarged, palpate proximal to carpus (flex carpus)
what two methods of declawing ensure removal of the ungual crest?
remove all to P3, or all (including ungual crest) butt base of P3
what is an onychectomy?
removal of a claw - declawing
how is a declaw operation performed basically?
guillotine nail clipper: blade in dorsal-distal interphalangeal joint and other distal to digital pad
why do some veterinarians leave the base of P3 in declawing?
preserve insertion of DDF and digital pad
why do some surgeons remove all of P3 in declawing
to prevent sequestrum
briefly describe a dewclaw removal in older dogs
prep, anesthetic, elliptical excision, ligate metatarsal and dorsal proper digital aa., disarticulate P1 from Mt1 if attached, if not just remove, suture
what type of fractures often occur in the radius and ulna?
how are simple fractures of the ulna and radius often treated?
with external casts
what is a Monteggia fracture?
fracture of the proximal 1/3 of the ulna with radial head luxation
what is the required when treating metacarpal/metatarsal fractures for weight bearing?
metacarpal/metatarsals #3 and #4 must be aligned properly
why are dogs dewclaws removed?
prevent catching and tearing on things
when are dewclaws of dogs best removed?
what is osteochondrosis?
disturbance of endochondrial ossification affecting articular cartilage
list three sites of osteochondrosis in the dog.
head of the humerus
trochlea of the humerus
medial coronoid process of the ulna
medial trochlea of talus
lateral condyle of the femur
are luxations of the shoulder common in dogs?
what helps prevent luxation of the shoulder?
thickenings of joint capsule (glenohumeral ligaments) and adjacent muscles
what helps prevent luxation of the elbow of the dog?
anconeal process in the olecranon fossa
what can cause degeneration of the elbow joint?
ununited anconeal process and fragmented medial coronoid process
what is the lateral coronoid process of the ulna used to determine in lateral radiographs?
subluxation of the elbow
how are ruptures of the collateral ligaments of the elbow diagnosed?
by the amount of supination of pronation allowed, compared to the unaffected limb.
where and when can the olecranon bursa be palpated?
at the termination of the long head of the triceps when affected
when does communication between the carpal synovial sacs become important?
when blocking the carpus in horses
what may be required to diagnose carpal fractures?
oblique radiographic views
what are the clinical signs of carpal luxation or subluxation?
plantigrade stance, nonweight bearing lameness
what causes puppy carpal weakness and how does it present?
insufficient exercises resulting in hyperextension of the carpus
what is carpal flexion syndrome
puppies stand on flexed carpi, they spontaneously recover
what are the clinical signs, treatment and prognosis of old age laxity of the carpus?
CS: plantigrade stance. No treatment is needed as dog does fine.
Of what clinical importance are superficial veins of the shoulder region?
must be retracted or ligated in surgical approaches to shoulder
how is the cephalic vein raised for venipuncture?
finger pressure across lateral, cranial, and medial sides of elbow
where is venipuncture usually performed on the cephalic vein
in the forearm above the carpus; start distally so that if you "flub" you can move up the arm
Why is the external jugular vein, which passes superficially up the neck, hard to perform venipuncture into?
what spinal nerves are involved in the panniculus response?
thoracic and lumbar nerves and lateral thoracic nerve from brachial plexus.
because spinal nerves pass caudoventrally, skin sensation is associated with what spinal cord segment?
segment 2 vertebrae cranial to level of skin
what is a common serious injury of the the nerves of the forelimb?
complete avulsion (tearing) of brachial plexus associated with HBC
does sensation to the caudolateral aspect of the arm rule out complete brachial plexus avulsion?why?
no, because the area is innervated by the intercostobrachialis nn. which doesn't arise from the brachial plexus
what results from damage to the suprascapular nerve?
how is loss of motor neurons of the limbs determined?
observance of gait; depression of tone and reflexes; palpation of muscle atrophy
what makes the point of the shoulder
what is the palpable groove between the two tubercles of the humerus?
bicipital (intertubercular) groove.
what is the palpable tendon in the intertubercular groove?
tendon of biceps brachii muscle
what small lateral process is distal to the greater tubercle?
how is the joint distal to the shoulder located?
by flexing and extending it - elbow