Card Set Information
What muscles must be transected to remove the entire forelimb, including the scapula?
All the extrinsic muscles of the forelimb
What is atrophy of supraspinatus and infraspinatus muscles causing a prominent scapular spine called? What causes it?
Sweeney; damage to suprascapular nerve
What results from radial nerve paralysis to the extensors of the thoracic limb?
Inability to stand, knuckling over of the digits
What is the most important layer that must be opposed when closing a paramedian midline incision?
External rectus sheath
What is the most important structure to close in a midline incision?
How would you locate the trachea for an ER tracheostomy?
Skin incision of the ventral neck, seperate the strap mm.
What muscle and nerve must be functional to bear weight on the pelvic limb?
Quadriceps m, femoral nerve
What muscles are paralyzed with obturator nerve damage, resulting in lateral slipping on a slick surface?
Why does an animal knuckle over on the pelvic limb with fibular nerve damage?
Paralysis of the extensors of the digits
What muscle does the facial nerve innervate? Which is of clinical significance?
Muscles of facial expression; orbicularis oculi m.
What muscles are innervated by the mandibular division of the trigeminal nerve?
Muscles of mastication
What do the 3,4,6 cranial n (oculomotor, trochlear, abducens) innervate?
Extrinsic muscles of the eye
What muscles are innervated by both cranial n 9 and 10 (glosso. and vagus)?
Muscles of pharynx
What is the injection of a substance into a muscle? How is it done?
Intramuscular (IM) injection; aspirate the syringe before injecting to make sure needle is not in a vessel
Why can a broken neck result in resp. paralysis?
Phrenic nerve to the diaphragm arises from the cervical and brachial plexuses
What is the panniculus (cutaneous trunci) response?
Contraction of the cutaneous trunci m. in response to a pin prick to the trunk
What is the reflex arc for the panniculus response?
Sensation from the skin passes craniodorsal to the spinal cord --> up the cord to lateral thoracic nerve --> out to the cutaneous trunci m.
Clinically, what is the panniculus response used to evaluate?
Level of the thoracic spinal cord damage
Where is the spinal cord damage if the panniculus response is absent caudal to level of 12th vertebrae?
Level of T10
For standing large animal flank sx, what must be blocked?
Dorsal and ventral branches of the abdominal nerves
What nerve must be considered when removing the anal glands? why?
The caudal rectal n; damage can cause paralysis of external anal sphincter --> fecal incontinence --> likely leading to early demise
Define clonus/ clonic muscular spasms?
Rapidly alternating involuntary muscular contraction and relaxation
How does a tetanic animal present?
Pump handle tail, Saw horse stance, Lockjaw, Sardonic grin
How does coonhoudn paralysis present?
Ascending flaccid paralysis
Describe the pathophysiology of tick paralysis
Blocks neuromuscular junctions resulting in flaccid paralysis that ascends the spinal cord
Describe the pathophysiology of a roarer/recurrent laryngeal n. damage
Paralysis of crico. dor. m. results in a roaring sound when breathing
What is a common serious injury of all the nerves to the forelimb?
Complete avulsion of the brachial plexus associated with HBC (hit by car)
What are the signs of complete avulsion of the brachial plexus?
Complete paralysis, extended flaccid limb, unable to support weight and dragging paw
What is Sweeney?
Damage to suprascapular nerve --> paralysis to supraspinatus and infraspinatous muscles --> lateral instability of shoulder joint
What is the most common and clinically significant nerve problem of the forelimb?
What are the 2 types of radial nerve injury?
High and low radial nerve injury
What are signs of high radial nerve paralysis?
Inability to bear wt, dropped elbow, knuckling over the digits
What are signs of low radial nerve damage?
Knuckling over on digits
What sensory loss is diagnosed for radial nerve injury?
Loss of sensation on dorsal manus
What results from femoral nerve injury? why?
Can't bear wt, can't extend stifle - b/c analgesia to saphenous nerve
Injury to which nerve causes lateral slipping on a slick surface?
What are signs of fibular (peroneal) nerve damage?
Knuckling over, analgesia of dorsal pes
How does an animal compensate for peroneal nerve damage?
By flipping the paw in advance
What is peroneal nerve paralysis similiar to in the thoracic limb?
Low radial nerve paralysis
What is an iatrogenic cause of ischiatic n. damage? What does it result in?
IM injection in rear limb; results in paresis/paralysis of rear limb
What is the definition of proprioception?
Sensing movements and position of the body parts
What tests are used to evaluate proprioception? Example.
Postural reactions. ie. placing animal of its dorsal paw should result in immediate adjustment to normal placement
What is the only part of the nervous system that will not result in weakness?
Cerebellum (& peripheral vestibular system)
What is the most common postural reaction used to screen for neurological problems?
Proprioceptive positioning (knuckling)
What is a neuro screening test to indicate there is a neurological problem but doesnt localize where the problem is?
Proprioceptive positioning (knuckling), postural reaction
For what does proprioceptive positioning (knuckling) test?
Conscious perception of the location of the limbs
What does loss of proprioception tell you clinically?
Doesn't localize a lesion, but is indication of neurological problem
What is done once screening indicates a neurological problem?
Procedures to localize the lesion to a specific part of the nervous system
What is a CSF tap and where is it done?
Removal of cerebrospinal fluid; from the subarachnoid space in the cisterna magna or lumbar cistern
What is epidural anesthesia, where is it commonly given?
Anesthetize the spinal n, thru the lumbosacral opening into the epidural space
Complete loss of motor activity
Weakness, partial loss of motor activity
What are the suffixes - paresis and -plegia used to describe?
Paresis and paralysis, respectively
Differentiate flaccid and spastic paresis or paralysis
: decreased or no tone in muscles
: increased tone/ hypertonicity
Lack of coordinated movements with or without spasticity or paresis
What can cause ataxia?
Lesions of the entire nervous system
Define intention tremor and what it indicates
A tremor that becomes worse with initiation of a movement and disappears at rest
Indicates cerebellar disease
Involuntary movement of eyes in rotatory, vertical, or horizontal directions
How does nystagmus at rest appear and what does it indicate?
Eyes move to the side of the lesion and snap back
Indicates vestibular dysfunction
Define dysmetria and what it indicates
Improper measuring of distance in muscular activity
Indicates cerebellar disease
How do you screen for neurological problems?
1. conciousness, behavior, seizures
2. stance and head position
3. gait and strength
4. proprioceptive positioning
Why is mental attitude/ conciousness, behavior, seizures observed in a neuroscreening test?
Screen for cerebrum and brain stem problems
What does observation of stance and head position of a neuroscreening test check?
What abnormal stance and head position indicate neurological problems (cerebellum/vestibular system)?
Head tilt, wide based stance; head tremor/bobbing
What does gait and strength observation evaluate?
Entire nervous system
What is gait checked for during a neurological screening test?
Proprioceptive deficits, paresis, circling, ataxia, dysmetria, scuffing, knuckling, or atrophy
What does abnormalities in gait indicate in neuro. screening?
Nervous system problem
Do gait abnormalities localize a neurological lesion?
no, just a neurological problem
How is strength tested during a neurological exam?
Push down on the standing animal
What does weakness indicate during a neuro. screening?
Nervous problem but NOT the cerebellum or peripheral vestibular system
What is the affect of UMNs damage on LMNs?
LMNs increase activity
To where do LMN signs localize the lesion?
Peripheral nerves, spinal cord, or segment of brain stem the LMN arises from
What does pointing your thumb down in LMN damage indicate?
Everything deceased or disappears
List 4 LMN disease signs (thumbs down)
1. Decreased or absent tone (hypotonia to atonia)
2. Decreased to absent reflexes (hypo- to areflexia)
3. Flaccid paralysis
4. Rapid atrophy
List 4 UMN disease signs (thumbs up)
1. Normal to increased muscle tone
2. Normal to inreased reflexes (hypereflexia)
3. Spastic paresis to paralysis
4. Slow atrophy
List how the reflexes are checked for the limbs
How is a withdrawal reflex performed?
Pinch the toe; normal response = withdrawal
How is tone evaluated?
Palpate the muscles of the limbs
What causes a coma?
Complete disconnection of the reticular activation system (RAS) from the cerebral cortex, usually due to severe brain stem lesion
List 3 primary deficits that may be seen with lesions to the cerebrum
2. Blind with normal pupillary responses
3. Behavior abnormalities
Unilateral cerebral lesions will cause ___ signs
How is brain stem disease characterized?
Abnormal gait + abnormal posture and cranial nerve deficits, decreased mental states, proprioception deficits and weakness
What is the range of decreased levels of consciousness due to brainstem lesions?
Depression to coma
What is the best evidence of brainstem lesions?
Multiple dysfunction of cranial nerves 3-12
When should brain stem disease be suspected?
If cranial n. abnormalities + UMN paresis, or decreased conciousness
How does a cerebellar lesion present?
Uncoordinated without paresis (no weakness), vestibular signs, and proprioceptive deficits
What do vestibular system lesions affect?
The ability to control posture in relationship to gravity and eye movemets in relationship to head movements
What are signs of vestibular disease?
Head tilt, nystagmus, asymmetric ataxia with possibly circling
What is the primary diagnostic concern with vestibular disease?
Differentiating peripheral (no paresis or depression) and central (paresis and depression) vestibular disease
What is the first deficit to show with a neurological deficit?
What does BAR stand for?
Bright, alert, and responsive
What does multiple dysfunction of cranial nerves indicate?
Brain stem lesion
What would cause a dropped jaw?
Paralysis of trigeminal nerve
Why is paralysis of the orbicularis oculi and loss of lacrimation the most vital results of facial nerve paralysis?
Drying of eye; animals are not vain
How is the auriculopalpebral nerve manipulated clinically? In what species?
Blocked to paralyze eyelids for eye procedures; large animals
How is the facial nerve commonly injured in the horse?
Lying on a halter buckle during sx
What cranial nerve is assoc. with: blindness
What cranial nerve is assoc. with: Anisocoria (unequal sized pupils)
Sympathetic, parasympathetic (3) (oculomotor)
What cranial nerve is assoc. with: Strabismus (uncontrolled deviation of the eye)
Oculomotor, trochlear, abducens
What cranial nerve is assoc. with: dropped jaw and head atrophy
What cranial nerve is assoc. with: Increased of decreased facial sensation
What cranial nerve is assoc. with: Facial paralysis
What cranial nerve is assoc. with: Deafness and/or loss of balance
What cranial nerve is assoc. with: Dysphagia (difficult swallowing)
What cranial nerve is assoc. with: Megaesophagus
What cranial nerve is assoc. with: Laryngeal paralysis
Vagus, recurrent laryngeal n.
What cranial nerve is assoc. with: Paralysis of the tongue
Paralysis of which nerve results in a weak tongue?
How is the facial/trigeminal reflex arc checked?
Prick the face, pulling away = intact trigeminal n.
Twitch of face muscles = intact facial nerve
What cranial nerve problem can be seen with middle ear infections?
Paralysis of the facial n. and resulting dry eye
What procedure can be used to facilitate the exam of the eye? How?
Auriculopalpebrae n. block, eliminates blinking and closing of eye
What are signs of damage to the recurrent laryngeal n?
Laryngeal paralysis / hemiplegia
: failure of glottic cleft to open
High pitched, whistling on inspiration, exercise intolerance
Discuss the clinical significance of the accessory n.
Little clinical sig
Describe the pupillary light reflex and what structures it involves?
Shinning a light in the eye, noting if pupil constricts; checks cranial nerves Optic and Oculomotor
Describe signs of facial nerve damage
Paralysis of muscles of facial expression resulting in a distorted face
Paralysis of orbicularis oris m. and ANS fibers to lacrimal gland, resulting in a dry eye
What is dysfunction of the sympathetic fibers to the eye?
List the cardinal signs of Horner's syndrome
Miosis (small pupil)
Enopthalmos (small eyes)
Ptosis (drooping eyelid)
Protrusion of 3rd eyelid
What results in swelling or draining (pus) below the carnivore's eye?
Carnassial tooth abscess (upper P4)
How is aging of dog by their teeth used practically in dogs?
Baby teeth in by 6 weeks
: vx time
Adult in by 6 mo
: spay/neuter time
Which dog teeth have three roots?
Last 3 on top
Which cat permanent teeth has 3 roots?
Upper PM4 (carnassial)
How is a nasogastric tube placed?
Thru the nostril and the ventral nasal meatus
A laryngotomy to open the larynx goes thru which paired muscles to expose the larynx?
Sternohyoid mm, middle "strap muscle"
The esophagus is accessible to sx in the ___ half of the neck region on the ___ side
What surgical landmark indicates the ventral midline of the larynx?
Cricothyroideus or bow tie muscle
Paralysis of what muscle results in "roarers" in horses?
cricoarytenoideus dorsalis m.
How is a tranquilized dog intubated?
Gently pull the tongue rostrally, push the soft palate up, hold the epiglottis down, direct the tube b/t the vocal folds into the trachea
What causes laryngeal paralysis?
Damage to recurrent laryngeal n. --> paralysis of crico. dor. m --> no opening to glottic cleft --> roaring sound when breathing
What is a roarer?
Dog or horse with laryngeal paralysis due to damage of recurrent laryngeal n --> paralysis of crico. dor. m.