Neuromuscular and Neurological System Flashcards

Question

# CN IV - Clinical Definition **What is cranial nerve IV (i.e., CN IV)?** **Where does it enter or emerge?** **What type of functional fibers does it contain?** **What is it's function?**

Answer 1

Cranial nerve IV refers to the ***trochlear nerve***. The trochlear nerve emerges from the midbrain. The trochlear nerve contains motor fibers. The trochlear nerve is responsible for rotating the eyeball inferiorly when the eyeball is ADducted (i.e., "inward and down"). * The trochlear nerve innervates the superior oblique muscle of the eye. **\*_Note:_ The trochlear nerve is the only cranial nerve that innervates contralateral structures** (e.g., the right trochlear nerve innervates the left superior oblique muscle of the eye). *_References:_* * *Moore et al. (8th ed.), pp.1072-1073 ("Trochlear Nerve")* * *Purves et al. (6th ed.), pp.A-8 to A-9 (Table A2)* * *Nolan, p.44 (Table 4), 62 (Table 5)* * *For more information about actions of the extraocular muscles, see Purves (6th ed.), pp.448-450.* * *NeuroLogic Examination: Cranial Nerve \> Anatomy (https://neurologicexam.med.utah.edu/adult/html/cranialnerve\_anatomy.html#01)* * *Cranial Nerve: Functional Anatomy and Clinical Evaluation (http://vmerc.uga.edu/CranialNerves/trochlear.html)*

Answer 2

* Multiple sclerosis * Myasthenia gravis *_Reference:_* * *Goodman and Fuller (4th ed.), pp.1484-1485 ("Multiple Sclerosis--Clinical Manifestations"), 1697 ("Myasthenia Gravis--Clinical Manifestations")*

Answer 3

* Eyeball in a resting position of hypertropia and extorsion (i.e., "up and outward") due to an unbalanced pull from the inferior oblique muscle * Diplopia when attempting a downward gaze in the ADducted position with the affected eye * _Example:_ If the left trochlear nerve was affected, attempting to look to the left and downward will cause diplopia because the right eyeball will remain relatively unchanged from it's resting position (see above) whereas the left eyeball will be ABducted (i.e., positioned laterally to the left) and rotated inferiorly. * Head tilt to the side opposite the side of the affected eye (i.e., right eye involvement = left head tilt) to reduce symptoms of diplopia (\*see image below) *_Reference:_* * *Nolan, Table 7, p.71*

Answer 4

* "H" test for extraocular movements (\*see image below) * Weakness or paralysis of one or more extraocular muscles results in heterotropia when the eyes move in the direction corresponding to the action of those muscles * _Example:_ Loss of motor control of the right superior oblique muscle (i.e., left trochlear nerve involvement) = heterotropia with diplopia when attempting a downward gaze with the right eye ADducted (i.e., attempting to look to the left and downward) *_Reference:_* * *Nolan, p.63,64 (Figure 7)*

Answer 5

Cranial nerve V refers to the ***trigeminal nerve***. The trigeminal nerve emerges from the pons. The trigeminal nerve contains both sensory and motor fibers. The trigeminal nerve is responsible for: * Sensation from the face, cornea, and anterior tongue * The skin on the face and scalp are innervated by the three divisions of the trigeminal nerve: ophthalmic (V1), maxillary (V2), and mandibular (V3) (\*see image below). * Muscles of mastication * Masseter * Temporalis * Medial pterygoid * Lateral pterygoid *_References:_* * *Moore et al. (8th ed.), pp.1073-1074 ("Trigeminal Nerve")* * *Purves et al. (6th ed.), pp.A-8 to A-9 (Table A2)* * *Nolan, p.44 (Table 4), p.72*

Answer 6

* Multiple sclerosis * Trigeminal neuralgia is highly characteristic of multiple sclerosis in a young person. * Myasthenia gravis * In particular, myasthenia gravis can cause weakness and fatigability of the muscles of mastication. *_Reference:_* * *Goodman and Fuller (4th ed.), p.1485 (Multiple Sclerosis--Clinical Manifestations), 1697 ("Myasthenia Gravis--Clinical Manifestations")*

Answer 7

***Trigeminal neuralgia*** (aka, *tic douloureux*) refers to severe electrical shock-like or stabbing pain that is strictly limited to the facial distribution of one or more divisions of the trigeminal nerve, or CN V: ophthalmic (V1), maxillary (V2), and mandibular (V3) (\*see image below). *_References:_* * *Louis et al. (13th ed.) (keyword: "trigeminal neuralgia")* * *Goodman and Fuller (4th ed.), p.1692*

Answer 8

* Sensory impairments of the face along the divisions of the trigeminal nerve * Trigeminal neuralgia may be present. * Impaired corneal reflex: No blinking of either eye when the cornea of the affected eye is touched, and blinking of both eyes when the cornea of the normal eye is touched * Weakness of the muscles of mastication (i.e., masseter, temporalis, lateral pterygoid, medial pterygoid) * If upper motor neuron pathways are involved, positive jaw-jerk reflex will be present. *\*_Note:_ See "CN V - Special Tests" flashcard for more details as well as references.*

Answer 9

**SENSORY ASSESSMENT OF THE FACE** * _Test procedure:_ Use a safety pin to assess discrimination between sharp (painful) stimuli and blunt stimuli in the three divisions of the trigeminal nerve (\*see below). Assess both sides of the face. The tested trigeminal nerve is on the same side being tested on the face (e.g., right trigeminal nerve = right side of the face). * _Ophthalmic (V1):_ Skin of the forehead above the eyebrows * _Maxillary (V2):_ Skin over the cheeks * _Mandibular (V3):_ Skin over the chin on each side of midline near the mental foramen * _Interpretation of results_ * _Normal:_ Full sensation (sharp and blunt) on both sides of the face * _Abnormal results on one or both sides of the face:_ * Reduced sharp and blunt sensations (aka, *hypoesthesia, hypesthesia*) * Reduced sharp (painful) sensation (aka, *hypoalgesia*) * Increased sharp and blunt sensations (aka, *hyperesthesia*) * Increased sharp (painful) sensation (aka, *hyperalgesia*) * Perception of pain resulting from a stimuli that is not normally painful (aka, *allodynia*) **ASSESSEMENT OF CORNEAL REFLEX** * _Test procedure:_ Ask the patient to direct his or her gaze to one side, keeping both eyes open. Approach the ADducted eye from the lateral side with a wisp of cotton that has been twisted to a point. Touch the cornea over the iris lateral to the pupil, taking care to avoid contacting the conjuctiva or sclera, or passing the cotton tip in front of the pupil. Repeat with the patient looking to the opposite side. * _Interpretation of results_ * _Normal:_ Immediate blinking of both eyes, occasionally with movement of the head away from the stimulus * _Abnormal:_ * No blinking of either eye when the cornea of the affected eye is touched, and blinking of both eyes when the cornea of the normal eye is touched * Due to injury of the ophthalmic division of the trigeminal nerve on the side of the affected eye * When the cornea of the affected eye is touched, the affected eye does not blink whereas the normal eye does. When the cornea of the normal eye is touched, the affected eye remains open whereas the normal eye blinks. * Due to injury of the facial nerve on the side of the affected eye **ASSESSMENT OF MUSCLES OF MASTICATION** * _Masseter, temporalis, and medial pterygoid_ * _Test procedure:_ Ask the patient to close the mouth and gently approximate the teeth. Palpate the masseter and temporalis muscles of both sides of the face as the patient bites hard. * _Interpretation of results:_ * _Normal:_ Equal and symmetric contractions of the masseter and temporalis; jaws cannot be separated when pushing down on the chin * _Abnormal:_ Unequal or asymmetric contractions of the masseter or temporalis * Due to injury of the trigeminal nerve on the side of the affected muscle of mastication * _Lateral pterygoid_ * _Test procedure:_ Ask the patient to push the jaw forward with the mouth slightly open. * _Interpretation of results:_ * _Normal:_ The jaw moves straight forward approximately 1 cm. * _Abnormal:_ Deviation of the jaw to one side * Due to injury of the trigeminal nerve on the same side of the jaw deviation (e.g., deviation of the jaw to the right = injury to the right trigeminal nerve) **JAW JERK REFLEX** * _Test procedure:_ Have the patient slightly open their mouth. Then place your finger on their chin and strike your finger with a reflex hammer. * _Interpretation of results_ * _Normal:_ No movement * _Abnormal:_ Brisk movement of the jaw upward as the mouth closes; may be indicative of an upper motor neuron problem *_References:_* * *Nolan, pp.74-77* * *NeuroLogic Exam: Cranial Nerve \> Normal (https://neurologicexam.med.utah.edu/adult/html/cranialnerve\_normal.html#16)* * *For more information about the jaw-jerk reflex, see ScienceDirect: Jaw-Jerk Reflex (https://www.sciencedirect.com/topics/medicine-and-dentistry/jaw-jerk-reflex).*

Answer 10

Cranial nerve VI refers to the ***abducens (abducent) nerve***. The abducens nerve emerges from the pons. The abducens nerve contains motor fibers. The abducens nerve is responsible for rotating the eye outward. * The abducens nerve innervates the lateral rectus muscle of the eye. *_References:_* * *Moore et al. (8th ed.), p.1074 ("Abducent Nerve")* * *Purves et al. (6th ed.), pp.A-8 to A-9 (Table A2)* * *Nolan, p.44 (Table 4), 62 (Table 5)*

Answer 11

Cranial nerve VII refers to the ***facial nerve***. The facial nerve emerges from the pons. The facial nerve contains both sensory and motor fibers. The facial nerve is responsible for: * Taste from anterior two-thirds of the tongue * Muscles of facial expression, including: * Frontalis * Orbicularis oculi * Zygomaticus major * Orbicularis oris * Tearing (lacrimal) glands * Salivary glands *_References:_* * *Moore et al. (8th ed.), pp.1076-1077 ("Facial Nerve")* * *Purves et al. (6th ed.), pp.A-8 to A-9 (Table A2)* * *Nolan, p.44 (Table 4), 83*

Answer 12

* Multiple sclerosis * Amyotrophic lateral sclerosis (ALS) * Myasthenia gravis * Bell's palsy *_Reference:_* * *Goodman and Fuller (4th ed.), p.1485 ("Multiple Sclerosis--Clinical Manifestations"), 1457* *("Amyotrophic Lateral Sclerosis--Clinical Manifestations"), 1697 ("Myasthenia Gravis--Clinical Manifestations")*

Answer 13

***Bell's palsy*** (aka, *Bell palsy, idiopathic facial paralysis*) refers to acute, unilateral paresis or paralysis of all of the muscles innervated by the facial nerve (CN VII) that appears spontaneously, over hours to days. Other associated signs and symptoms include dry eyes (i.e., decreased tearing), dry mouth (i.e., decreased salivation), dysarthria, impaired taste on the anterior two-thirds of the tongue on the affected side, and a weakened or absent corneal reflex (i.e., minimal to no blinking of the affected eye when the cornea of either eye is touched). In contrast, an upper motor neuron lesion (e.g., following a middle cerebral artery stroke) will result in weakness of only the inferior facial muscles on the contralateral side. *_References:_* * *Louis et al. (13th ed.) (keyword: Bell palsy)* * *Purves (6th ed.), p.385 ("Clinical Applications")*

Answer 14

Electrical stimulation of the facial muscles of expression

Answer 15

* See "Bell's Palsy - Clinical Definition" * Inability to completely close one or both eyes (i.e., lagophthalmos) can result in an observable Bell phenomenon *_References:_* * *Nolan, p.84*

Answer 16

***Bell phenomenon*** is a defensive reflex mechanism characterized by the upward and inward deviation of the affected eye (i.e., eye supraduction) when attempting to close that eye. Normally, Bell phenomenon helps to keep the eye moist and protected during eye closure. Bell phenomenon is observable when closure of the eyelid is incomplete, and an observable Bell phenomenon is associated with injury to the facial nerve (CN XII). *_References:_* * *Nolan, p.82* * *Louis (13th ed.) (keyword: Bell phenomenon)* * *ScienceDirect: Bell's Phenomenon (https://www.sciencedirect.com/topics/medicine-and-dentistry/bells-phenomenon)*

Answer 17

**ASSESSEMENT OF CORNEAL REFLEX** * See "CN V - Special Tests" flashcard. **ASSESSMENT OF MUSCLES OF FACIAL EXPRESSION** * _Test procedure_: Ask the patient to perform the following movements associated with the actions of the muscles of facial expression. * _Orbicularis oris:_ "Purse or pucker your lips as if whistling or kissing." * _Zygomaticus major:_ "Smile widely, and show your teeth." * _Orbicularis oculi:_ " Close your eyes tightly." * _Frontalis:_ "Raise the eyebrows." * _Interpretation of results_ * _Normal_ * _Frontalis:_ The eyebrows rise, producing wrinkles in the forehead. * _Orbicularis oculi:_ Eye closure is symmetric; equal strength (i.e., resistance) when attempting to gently pry the eyes open * _Zygomaticus major:_ Both corners of the mouth move laterally upon smiling; smile is symmetrical * _Orbicularis oris:_ Lips on both sides of the face come together upon pursing or puckering the lips * _Abnormal:_ Asymmetrical or absent facial expressions * In asymmetrical facial expressions, the involved facial nerve is on the same side as the affected side of the face. **ASSESSMENT OF TASTE** * _Test procedure:_ Ask the patient to stick out his or her tongue. Using a cotton applicator moistened with the test solution, apply dilute solutions of glucose (sweet), sodium chloride (salty), citric acid (sour), quinine (bitter), and water (i.e., control stimulus) to either side of the tongue separately. Ask the patient to indicate what he or she is tasting by pointing to one of the given cards with the following labels: SWEET, SALTY, SOUR, BITTER, and WATER. * _Interpretation of results:_ * _Normal:_ Patient is able to correctly identify each test solution. * _Abnormal:_ * Absence of taste (i.e., ageusia) * Decreased taste sensation (i.e., hypogeusia) *_Reference:_* * *Nolan, pp.82-83*

Answer 18

Cranial nerve VII refers to the ***vestibulocochlear (auditory) nerve***. The vestibulocochlear nerve emerges from the pons. The vestibulocochlear nerve contains special sensory fibers. The vestibulocochlear nerve is responsible for balance (semicircular canals, utricle, saccule) and hearing (organ of Corti). *_References:_* * *Moore et al. (8th ed.), pp.1078-1079 ("Vestibulocochlear Nerve")* * *Purves et al. (6th ed.), pp.A-8 to A-9 (Table A2)* * *Nolan, p.44 (Table 4)*

Answer 19

Cranial nerve IX refers to the ***glossopharyngeal nerve***. The glossopharyngeal nerve emerges from the medulla oblongata. The glossopharyngeal nerve contains both sensory and motor fibers. The glossopharyngeal nerve is responsible for: * Taste for the posterior one-third of the tongue * Sensation for posterior tongue and oropharynx * Salivary gland * Conveying impulses from the baroreceptors in the carotid sinus *_References:_* * *Moore et al. (8th ed.), pp.1079-1080 ("Glossopharyngeal Nerve")* * *Purves et al. (6th ed.), pp.A-8 to A-9 (Table A2)* * *Nolan, p.44 (Table 4), 96*

Answer 20

Cranial nerve X refers to the ***vagus nerve***. The vagus nerve emerges from the medulla oblongata. The vagus nerve contains both sensory and motor fibers. The vagus nerve is responsible for: * Muscles of the larynx (for phonation), pharynx, and soft palate *_References:_* * *Moore et al. (8th ed.), pp.1081-1083 ("Vagus Nerve")* * *Purves et al. (6th ed.), pp.A-8 to A-9 (Table A2)* * *Nolan, p.44 (Table 4), 62 (Table 5)*

Answer 21

* Amyotrophic lateral sclerosis (ALS) * Lateral medullary (Wallenberg) syndrome secondary to infarction of the lateral medulla and posteroinferior cerebellum * Characterized by vertigo, ipsilateral ataxia, Horner syndrome (due to damage of descending sympathetic fibers), impairment of sensation in the ipsilateral portion of the face and contralateral portion of the torso and limbs, and dysphagia * Myasthenia gravis * In particular, weakness and fatigability of the palatal and pharyngeal muscles due to impairment of the vagus nerve can result in dysphagia. *_References:_* * *Goodman and Fuller (4th ed.), p.1457 ("Amyotrophic Lateral Sclerosis--Clinical Manifestations"), 1516 ("Vertebral and Posterior Inferior Cerebellar Artery Syndrome"), 1697 ("Myasthenia Gravis--Clinical Manifestations")* * *Medscape: Vertebrobasilar Artery Stroke Syndromes (https://emedicine.medscape.com/article/323409-overview#a7)*

Answer 22

Specific to vagus nerve: * Dysphonia (i.e., a change in voice quality in which the voice sounds hoarse) * Abnormal deviation of the uvula at rest or during phonation Specific to both the glossopharyngeal and vagus nerves: * Dysphagia * Note that dysphagia can also indicate involvement of the trigeminal nerve, facial nerve, or hypoglossal nerve. * Abnormal gag reflex *\*_Note:_ See "CN IX and CN X - Special Tests" for more information and references.*

Answer 23

**ASSESSMENT OF SWALLOWING** * _Test procedure:_ Have the patient drink a glass of water and report his or her ease with swallowing. * Assessment of swallowing examines both the glossopharyngeal and vagus nerves. Note that three other cranial nerves are involved in the action of swallowing: trigeminal nerve, facial nerve, and hypoglossal nerve. * _Interpretation of results:_ * _Normal:_ Swallowing is free and unhindered. * _Abnormal:_ Swallowing is difficult (i.e., dysphagia). **ASSESSEMENT OF UVULA AND SOFT PALATE** * _Test procedure:_ With the patient's mouth open and the tongue kept relaxed on the floor of the mouth, assess the shape and resting position of the uvula. Then have the patient say, "Ah," and observe the movement of the uvula and soft palate during phonation. * Assessment of the uvula and soft palate primarily examines the vagus nerve. * _Interpretation of results_ * _Normal:_ * At rest, the uvula is symmetric in shape and located essentially in the middle of the mouth. * During phonation, there is symmetric elevation of the soft palate without movement of the uvula in either direction. * _Abnormal:_ * At rest, there is a grossly apparent asymmetry of the soft palate or deviation of the uvula. * During phonation, inability to elevate the soft palate on the involved results in deviation of the uvula away from the affected side (e.g., deviation of the uvula to the left = right vagus nerve involvement) **ASSESSMENT OF GAG REFLEX** * _Test procedure:_ With the mouth open, gently touch the lateral pharyngeal wall of one side with a tongue depressor or a cotton-tipped applicator. Repeat with the other side. * Assessment of the gag reflex examines both the glossopharyngeal and vagus nerves. * _Interpretation of results:_ * _Normal:_ Strong contraction of the upper pharyngeal muscles (gagging) * _Abnormal:_ * Normal gag reflex with stimulation of the normal side, and loss of gag reflex with stimulation on the involved side * Due to injury of the glossopharyneal nerve on the involved side * Absent gag reflex with stimulation on both sides * Involvement of both the glossopharyngeal and vagus nerves, OR... * Possibly due to aging process with no involvement of the glossopharyngeal or vagus nerves *_Reference:_* * *Nolan, pp.100-101*

Answer 24

Cranial nerve X refers to the ***spinal accessory nerve***. The spinal accessory nerve emerges from the medulla oblongata. The spinal accessory nerve contains motor fibers. The spinal accessory nerve is responsible for innervating the sternocleidomastoid and trapezius (upper, middle, lower) muscles. *_References:_* * *Moore et al. (8th ed.), p.1083 ("Spinal Accessory* *Nerve")* * *Purves et al. (6th ed.), pp.A-8 to A-9 (Table A2)* * *Nolan, p.44 (Table 4), 62 (Table 5)*

Answer 25

Cranial nerve X refers to the ***hypoglossal nerve***. The hypoglossal nerve emerges from the medulla oblongata. The hypoglossal nerve contains motor fibers. The hypoglossal nerve is responsible for tongue movements. * The hypoglossal nerve innervates the intrinsic and extrinsic muscles of the tongue. *_References:_* * *Moore et al. (8th ed.), pp.1084-1085 ("Hypoglossal Nerve")* * *Purves et al. (6th ed.), pp.A-8 to A-9 (Table A2)* * *Nolan, p.44 (Table 4), 62 (Table 5)*

Answer 26

* Amyotrophic lateral sclerosis (ALS) * Myasthenia gravis * In particular, weakness and fatigability of the tongue muscles can result in dysphagia. *_Reference:_* * *Goodman and Fuller (4th ed.), p.1457 ("Amyotrophic Lateral Sclerosis--Clinical Manifestations"), 1697 ("Myasthenia Gravis--Clinical Manifestations")*

Answer 27

* Atrophy of the tongue on the affected side * Fibrillations (i.e., small, contraction-like movements) of the tongue when it is at rest * Abnormal deviation of the tongue when the tongue is protruded * Weakness with lateral movements of the tongue * Difficulty with lingual sounds, or sounds produced by the tongue (e.g., "la la la") * Lingual sounds require pushing the tongue against the hard palate. * Dysphagia * Note that injury to CN V, CN VII, CN IX, and CN X can also result in dysphagia. * Impaired food manipulation with the tongue * Difficulty with breathing * Due to the tendency of the tongue to fall backward into the oropharynx *_Reference:_* * *Nolan, p.107*

Answer 28

**ASSESSMENT OF TONGUE SHAPE** * _Test procedure:_ Examine the mass and contour of the tongue. * _Interpretation of results_ * _Normal:_ Symmetric shape of the tongue * _Abnormal:_ Atrophy of the tongue on the same side as the affected hypoglossal nerve; fibrillations may be present at rest **ASSESSMENT OF TONGUE PROTRUSION** * _Test procedure:_ Instruct the patient to "stick out your tongue." * _Interpretation of results_ * _Normal:_ Tongue remains in midline * _Abnormal:_ Tongue deviates to the same side as the affected hypoglossal nerve; the affected side of the tongue may appear wrinkled and slightly elevated due to the pull of the muscles on the normal side **ASSESSMENT OF TONGUE STRENGTH** * _Test procedure:_ Ask the patient to push the tongue into the cheek on one side. Press on the cheek in an attempt to force the tongue out of the cheek. Repeat on the other side. * _Interpretation of results_ * _Normal:_ Equal strength of the tongue on both sides * _Abnormal:_ Unequal strength of the tongue on one side * Unilateral hypoglossal nerve damage will be characterized by a relative ease in pushing the tongue out of the cheek on the uninvolved side (e.g., easier to push the tongue out of the cheek on the right side = left hypoglossal nerve involvement) **ASSESSMENT OF LINGUAL SOUNDS** * _Test procedure:_ Ask the patient to say lingual sounds such as "la la la," "tee tee tee," or "dee dee dee." * _Interpretation of results_ * _Normal:_ Patient is able to articulate the lingual sounds. * _Abnormal:_ Patient is unable to articulate the lingual sounds. *_Reference:_* * *Nolan, pp.105, 107*

Answer 29

Cataracts and macular degeneration reflect visual acuity deficits. ***Cataracts*** refers to opacities in the lens of the eye (i.e., "clouding of the lens") that results in a loss of transparency in that lens. ***Macular degeneration*** (aka, *age-related macular degeneration*) refers to a loss of central vision due to damage to the macula lutea, a region of the retina that supports high visual acuity. * The loss of visual acuity associated with cataracts or macular degeneration only affects the eye of origin (e.g., cataracts of the right eye = right eye involvement). Glaucoma reflects a visual field deficit. ***Glaucoma*** refers to a loss of peripheral vision due to inadequate drainage of the eye’s aqueous humor that leads to increased intraocular pressure, reduced blood supply to the eye, and eventual damage to the retinal neurons. * The loss of visual field associated with glaucoma only affects the eye of origin (e.g., glaucoma of the right eye = right eye involvement). *_Reference:_* * *Purves (6th ed.), p.234, 237 ("Clinical Applications: Macular Degeneration"), 263 ("Clinical Applications: Visual Field Deficits" ["Damage to the retina or to one of the optic nerves..."])*

Answer 30

***Clonus*** refers to oscillatory contractions and relaxations of muscles in response to muscle stretching (e.g., stretching the ankle plantarflexor muscles by passively and rapidly placing the foot into ankle dorisflexion). Clonus is associated with upper motor neuron syndrome and is therefore possibly caused by disruption of the regulatory influences exerted by the upper motor neurons on the lower motor neurons.

Answer 31

***Tenodesis action*** refers to the automatic and passive flexion of the fingers and thumbs that is produced when the extrinsic flexors of the digits of the hand (i.e., flexor digitorum profundus, flexor digitorum superficialis, flexor pollicis longus) are stretched in a position of wrist extension (\*see image below). *_Reference:_* * *Neumann (3rd ed.), p.274 ("Passive Finger Flexion via 'Tenodesis Action' of the Extrinsic Digital Flexors"*

Answer 32

Finger flexion with wrist extension *_References:_* * *Neumann (3rd ed.), p.274 ("Special Focus 8.6")* * *DMNMC II --\> SCI Unit Lecture HO (p.58)*

Answer 33

1.37 m/s, or 3 mph

Answer 34

The ***Babinski sign*** (\*see image below) refers to the atypical fanning of the toes and the extension of the big toe when stroking the sole of the foot. * In adults, the Babinski sign is associated with damage to the corticospinal tract. * In infants before the maturation of the corticospinal pathway, the Babinski sign occurs as a result of the incomplete upper motor neuron control of local motor neuronal circuitry. ***Hoffmann sign*** is the upper extremity equivalent of the Babinski sign and, if present in adults, also indicates damage along the corticospinal tract. The Hoffmann sign is characterized by flexion or ADduction of the 1st interphalangeal (IP) joint of the thumb as well as flexion of the fingers when the distal phalanx of the middle finger is flicked briskly. *_References:_* * *Purves (6th ed.), p.403* * *Magee (6th ed.), p.200* * *Physiopedia: Hoffmann's Sign (https://physio-pedia.com/Hoffmann%27s\_Sign#:~:text=A%20positive%20Hoffmann%27s%20sign%20is%20suggestive%20of%20corticospinal,anxiety%20will%20also%20result%20in%20a%20positive%20sign.)*

Answer 35

***Knee-jerk reflex*** (aka, myotatic reflex, quadriceps tendon reflex, patellar tendon reflex) * _Involuntary movement elicited:_ Knee extension when striking the patellar ligament (aka, "patellar tendon") * _Innervations_ * _Peripheral:_ Femoral nerve * _Segmental:_ L2, L3, and L4 spinal nerves ***Ankle-jerk reflex*** (aka, Achilles tendon reflex) * _Involuntary movement elicited:_ Ankle plantarflexion when striking the Achilles (calcaneal) tendon * _Innervations_ * _Peripheral:_ Tibial nerve * _Segmental_ * _Gastrocnemius:_ S1 and S2 spinal nerves * _Soleus:_ L5, S1, and S2 spinal nerves ***Triceps brachii reflex*** * _Involuntary movement elicited:_ Elbow extension when striking the triceps brachii tendon * _Innervations_ * _Peripheral:_ Radial nerve * _Segmental:_ C6, C7, C8, and T1 spinal nerves ***Brachioradialis reflex*** * _Involuntary movement elicited:_ Elbow flexion when striking the brachioradialis muscle belly * _Innervations_ * _Peripheral:_ Radial nerve * _Segmental:_ C5 and C6 spinal nerves ***Biceps brachii reflex*** * _Involuntary movement elicited:_ Elbow flexion when striking the biceps brachii tendon * _Innervations_ * _Peripheral:_ Musculocutaneous nerve * _Segmental:_ C5 and C6 spinal nerves Deep tendon reflexes are graded as follows: * 0 = No reflexes * +/1 = Diminished reflexes, or reflexes elicited with reinforcement * ++/2 = Normal * +++/3 = Brisk, increased reflexes * ++++/4 = Non-sustained clonus * +++++/5 = Sustained clonus *_References:_* * *ECS I --\> "Complete Neuro Screen Examination (video guide)" Word doc* * *See ECS I lecture, "Neuroscreening" (p.11).* * *For more information about reflex circuits (aka, reflex arcs), see Purves (6th ed.), p.10-11, 366.*

Answer 36

***Heterotropia*** refers to misalignment of the eyes (i.e., the two eyes don't line up in the same direction) when the patient is given free central vision and is asked to fixate on some distant point. Heterotropias are named for the direction of deviation of the affected eye (e.g., exotropia refers to ABduction or turning outward of the affected eye). ***Strabismus*** (aka, "crossed eyes," "wall eyes") is a term that is sometimes used to also refer to misalignment of the eyes. *Lateral strabismus* is another name for exotropia. *_References:_* * *Nolan, pp.63-64 (Table 6)* * *MedlinePlus: Eye Movement Disorders (https://medlineplus.gov/eyemovementdisorders.html)*

Answer 37

***Ptosis*** is a condition in which the superior eyelid droops. *_Reference:_* * *Nolan, p.47*

Answer 38

***Multiple sclerosis*** (aka, "multiple scars") refers to a chronic neuroimmunologic disease of the central nervous system (i.e., the brain and spinal cord) that is characterized by (1) inflammation of the sheaths of myelin around axons, (2) demyelination, (3) loss of axons, and (4) pathological apoptosis of the neurons due to demyelination. Multiple sclerotic plaques (i.e., lesions) can be found in both the white and gray matter. \*_Review:_ White and gray matter can be found in the brain (i.e., the cerebral cortex of the cerebrum) and spinal cord. White matter is composed of groups of myelinated axons, and gray matter is composed of the cell bodies of neurons (\*from Vander's [15th ed.], pp.173, 176). *_References:_* * *Goodman and Fuller (4th ed.), pp.1481, 1483* * *See multiple sclerosis lecture from Neurology Medicine.*

Answer 39

**_Gender:_** Female **_Age:_** 15-45 years **_Ethnicity:_** White **_Past medical history:_** * Family history of multiple sclerosis (genetic predisposition) or autoimmune diseases * Autoimmune disorders such as rheumatoid arthritis *_References:_* * *Goodman and Fuller (4th ed.), p.1482 ("Incidence," "Etiology and Risk Factors")* * *See multiple sclerosis lecture from Neurology Medicine.*

Answer 40

Genetic inheritance Inflammatory processes associated with MS is thought to be due to an underlying autoimmune disorder. *_Reference:_* * *Goodman and Fuller (4th ed.), p.1482 ("Etiologic and Risk Factors")*

Answer 41

* The most common form of MS is called ***relapsing-remitting MS (RRMS)***. The condition is characterized by *relapses* (aka, attacks, exacerbations), which are periods of new or increased MS-related signs and symptoms that last at least 24 hours and up to 1-2 months on average. Relapses are followed by stable periods of *remissions* that are marked by either full or partial recovery. * Heat intolerance * Uhthoff sign (aka, Uhthoff phenomenon), or new or worsening neurologic symptoms that occur with elevations in temperature (often during exercise or a hot shower) * Fatigue * Burning, neuropathic pain * Lhermitte sign (aka, "barber-chair" sign), or a momentary electric sensation that usually radiates from the back of the neck to the lower back and possibly into one or more limbs. Lhermitte sign is typically evoked by neck flexion or a cough. * Sensory ataxia * Upper motor neuron signs and symptoms (e.g., spasticity, loss of volitional movement, clonus, positive Babinski sign) * Cranial nerve involvement: * Optic neuritis due to the optic nerve being an extension of the cerebral cortex * Clinical presentation usually associated with lesions involving CN III (oculomotor) to CN XII (facial nerve) at the brainstem * _Examples:_ Trigeminal neuralgia, diplopia, dysarthria, dysphagia * _Note:_ CN X (trigeminal nerve) and CN XII (facial nerve) are involved in the action of swallowing. *_References:_* * *Goodman and Fuller (4th ed.), pp.1484-1485 ("Clinical Manifestations")* * *See Goodman and Fuller (4th ed.), pp.1481-1482 for more information about the subtypes of multiple sclerosis.* * *Louis et al. (13th ed.) (keyword: "multiple sclerosis")* * *See multiple sclerosis lecture from DMNMC II.* * *For information about cranial nerves and swallowing, see Oxford Medicine Online: The Lower Cranial Nerves and Swallowing (https://oxfordmedicine.com/view/10.1093/med/9780198569381.001.0001/med-9780198569381-chapter-020#:~:text=It%20involves%20the%20synergistic%20action%20of%20at%20least,seen%20in%20association%20with%20other%2C%20obvious%2C%20neurological%20problems).* * *Coach K's Lecture Materials --\> "Multiple Sclerosis and Guillain Barre"*

Answer 42

**_More favorable prognosis_** * Relapsing-remitting MS * Female * Onset before 30 years of age * Strong recovery after relapses * Long interval between relapses * Primarily sensory symptoms * Expanded Disability Status Scale (EDSS) score of less than 4 * Monoregional involvement **_Less favorable prognosis_** * Primary progressive MS or secondary progressive MS * ***Primary progressive MS*** is a subtype of MS that is characterized by a steady decline in neurologic function from the outset with episodes of minimal recovery. * ***Secondary progressive MS*** is a subtype of MS that is characterized by an initial pattern of relapsing-remitting MS followed by a change to a progressive course with a steady decline in function and fewer acute relapses. * Male * Onset after 40 years of age * Frequent relapses (greater than or equal to x2 per year) * Poor recovery following relapses * Development of motor symptoms * Decreased cognition * Brainstem or cerebellar involvement *_References:_* * *See multiple sclerosis lecture from DMNMC II.* * *TherapyEd Review Study Guide, p.158* * *Goodman and Fuller (4th ed.), pp.1481-1482*

Answer 43

* Progressive resistive exercises often result in a feeling of increased fatigue and weakness rather than a feeling of increased strength. Short breaks with energy conservation can make this fatigue less prominent. * Energy conservation strategies (e.g., movement modifications) and cooling strategies (e.g., cooling vests) to address fatigue and improve activity tolerance during the day * Patients with MS will have poor exercise tolerance as a result of respiratory muscle dysfunction. * Education on creating or accessing an "equipment closet" with various assistive devices, orthotics (e.g., braces), and exercise equipment that can be used to maintain level of physical activity and functional independence during relapses * Instruction on movement strategies that compensate for impairments (e.g., compensating for sensory ataxia by relying more on visual or vestibular system) *_References:_* * *Goodman and Fuller (4th ed.), p.1484 ("Clinical Manifestations"), 1492-1493 ("Special Implications for the Therapist")* * *See multiple sclerosis lectures from DMNMC II and Neurology Medicine.* * *For more information about sensory ataxia, see personal outline for DMNMC II intervention practical.*

Answer 44

***Guillain-Barré syndrome (GBS)*** has several distinct subtypes, and the most common subtype is called *acute inflammatory polyradiculoneuropathy*. This subtype of GBS refers to a collection of signs and symptoms that manifests as inflammation and demyelination of the peripheral nerves and spinal nerves, resulting in the formation of lesions throughout the PNS from the spinal nerve to the distal termination of both motor and sensory fibers. _Note:_ *Miller-Fisher syndrome* is another subtype of GBS that involves the cranial nerves. Miller-Fisher syndrome is characterized by three features: weakness or paralysis of the extraocular muscles (ophthalmoplegia) with sluggish pupillary light reflexes, sensory ataxia (i.e., loss of voluntary motor movement associated with a loss of joint proprioception), and areflexia. There is relative sparing of strength in the extremities and trunk. Facial weakness and sensory loss in the limbs may also occur. *_References:_* * *Medscape: Guillain-Barré syndrome (https://emedicine.medscape.com/article/315632-overview)* * *Goodman and Fuller (4th ed.), p.1687 ("Overview and Definition")* * *For information about ataxia, see personal outline for DMNMC II intervention practical; Purves (6th ed.), p.76.* * *For information about Miller-Fisher syndrome, see NIH Genetics Home Reference: Guillain-Barré Syndrome--"Description" (https://ghr.nlm.nih.gov/condition/guillain-barre-syndrome); Goodman and Fuller (4th ed.), pp.1687-1688.*

Answer 45

**_Gender:_** Male **_Age:_** Peaks in frequency around young adulthood (15-35 years old) and older adulthood (50-80 years old) **_Ethnicity:_** White **_Past medical history:_** Infectious illnessness (e.g., respiratory or gastrointestinal) *_References:_* * *Medscape: Guillain-Barré Syndrome--Epidemiology (https://emedicine.medscape.com/article/315632-overview#a5)* * *Goodman and Fuller (4th ed.), p.1687 ("Incidence")*

Answer 46

Bacterial and viral infections, surgery, and vaccinations Inflammatory processes associated with GBS is thought to be due to an autoimmune response. *_Reference:_* * *Goodman and Fuller (4th ed.), pp.1687-1688 ("Etiology and Risk Factors")*

Answer 47

* First neurologic symptom is often paresthesia in the toes * Rapidly ascending symmetric motor weakness (distal to proximal) and distal sensory impairments * Weakness usually begins in the legs and then spreads to involve the arms, trunk, and facial muscles. * Other lower motor neuron signs and symptoms (e.g., flaccid paralysis, areflexia) * Loss of control of respiratory skeletal muscles with progression of GBS *_Reference:_* * *Goodman and Fuller (4th ed.), p.1688 ("Clinical Manifestations")*

Answer 48

After 1 year, 67% of patients with GBS have complete recovery, but 20% of patients will still have significant disability. After 2 years, 8% will not have recovered. *_Reference:_* * *Goodman and Fuller (4th ed.), p.1689 ("Prognosis")*

Answer 49

* Focus of physical therapy is to prevent the development of complications associated with immobilization * Skin care to prevent skin breakdown * Inspect the skin regularly, and follow skin care prevention protocols. * Positioning or splinting of the extremities affected by paresis or paralysis to prevent the development of contractures * Respiratory care to maintain clear airways and prevent atelectasis * Postural drainage, upright positioning and mobilization, coughing, and deep breathing * Monitoring for respiratory failure * Pulse oximetry, signs of rising PCO2 (e.g., tachypnea, confusion) * Provide gentle stretching and active or active-assistive exercise at a level consistent with the person’s muscle strength (e.g., as during aquatic therapy or with neuromuscular facilitation techniques) * Overstretching and overuse of painful muscles may result in a prolonged recovery period or a lack of recovery. *_Reference:_* * *Goodman and Fuller (4th ed.), pp.1689-1690*

Answer 50

***Amyotrophic lateral sclerosis*** (ALS; aka, *Lou Gehrig's disease*) is a progressive motor neuron disease characterized by degeneration of both lower and upper motor neurons, resulting in progressive muscle wasting (amyotrophy) and gliotic hardening (sclerosis of the neuroglial cells). _Note:_ Degeneration of motor neurons associated with amyotrophic lateral sclerosis involves the upper motor neurons in the cerebral (motor) cortex and corticospinal tract as well as lower motor neurons in the brainstem and spinal cord, spinocerebellar tracts, and dorsal columns. *_References:_* * *Goodman and Fuller (4th ed.), p.1455 ("Overview and Definition"), 1456 ("Pathogenesis")* * *For more information about alpha motor neurons, see Purves (6th ed.), p.361.*

Answer 51

**_Gender:_** Male **_Age:_** 50 years or older *_Reference:_* * *Goodman and Fuller (4th ed.), p.1456 ("Incidence and Etiologic and Risk Factors")*

Answer 52

The cause of ALS is unknown. *_Reference:_* * *Goodman and Fuller (4th ed.), 1456 ("Incidence and Etiologic and Risk Factors")*

Answer 53

Patients with ALS will demonstrate both lower and upper motor signs and symptoms. * **_Lower motor neuron signs and symptoms_** * Insidiously developing asymmetrical weakness, usually of the distal aspect of one limb progressing to weakness of the contiguous muscles * Extensor muscles become weaker than flexor muscles, especially in the hands * Weakness is due to progressive wasting and atrophy of muscles. Upper and lower limbs are usually affected first, with progression to the facial muscles via CN XII involvement (\*see below). * Cranial nerve involvement that result in dysarthria, dysphagia, and dysphonia * CN VII (facial nerve) * Cranial nerves originating from the medulla oblongata (aka, the "bulb"): CN IX (glossopharyngeal nerve) to CN XII (hypoglossal nerve) * **_Upper motor neuron signs and symptoms_** * Spasticity * Increased or brisk reflexes with clonus * Babinski sign is positive * May also be positive for Hoffmann sign Other signs and symptoms include: * *Respiratory difficulties* due to loss of control of the respiratory skeletal muscles * *Cognitive impairments* (e.g., deficiencies in attention and language comprehension) due to involvement of the cerebral cortex *_Reference:_* * *Goodman and Fuller (4th ed.), p.1455 ("Overview and Definition"), 1457-1459 ("Clinical Manifestations")*

Answer 54

The course of ALS is relentlessly progressive. Death usually occurs within 2 to 5 years, resulting mainly from pneumonia caused by respiratory compromise. *_Reference:_* * *Goodman and Fuller (4th ed.), p.1462 ("Prognosis")*

Answer 55

* Provide interventions that are appropriate for the current stage of ALS (i.e., independent, practically independent, and dependent), activity tolerance, and the predicted progression of the disease. * See Goodman and Fuller (4th ed.), Table 31-2, p.1463. * To prevent the development of respiratory complications, monitor for signs and symptoms of respiratory impairment (e.g., shortness of breath, poor cough reflex, headache). Teach patients to use their abdominal muscles to increase inspiration and expiration when the muscles of the diaphragm and intercostal muscles become weak. *_Reference:_* * *Goodman and Fuller (4th ed.), pp.1462-1464 ("Special Implications for the Therapist")*

Answer 56

***Cerebrovascular accident*** **(CVA; aka, *stroke*)** refers a loss of neurological function caused by an abrupt interruption of blood flow to the brain. The interruption of blood flow deprives neurons of oxygen and important nutrients; within a few minutes, affected neurons either die or are left badly damaged. *_Reference:_* * *See "Year 3" --\> "Fall 2019 (Remedial Clinical Rotation #2)" --\> "Clinical Resources" --\> "PT Review Series" --\> "CVA" --\> "CVA" Word doc*

Answer 57

Cerebrovascular accidents are categorized based on the underlying cause: * ***Ischemic strokes*** are characterized by insufficient blood flow to the brain. Insufficient blood flow may be due to either arterial occlusion (e.g., as a result of thrombosis or embolism) or systemic hypoperfusion. * _Example:_ Middle cerebral artery syndrome * ***Hemorrhagic strokes*** are characterized by a leakage of blood within or around the brain after an artery ruptures. * _Example:_ Intracerebral hemorrhage occuring at the cerebellum *_References:_* * *See "Year 3" --\> "Fall 2019 (Remedial Clinical Rotation #2)" --\> "Clinical Resources" --\> "PT Review Series" --\> "CVA" --\> "CVA" Word doc* * *For more information about middle cerebral artery syndrome, see Goodman and Fuller (4th ed.), p.1514 ("Middle Cerebral Artery Syndrome").* * *For more information about cerebellar hemorrhages, see Goodman and Fuller (4th ed.), p.1524 ("Cerebellum").*

Answer 58

***Middle cerebral artery (MCA) syndrome*** refers to a collection of signs and symptoms that are associated with an ischemic stroke involving the middle cerebral artery. _Review:_ In general, the middle cerebral artery supplies blood to the following areas of the brain: * Frontal lobe (especially Broca's area in the cerebral cortex of the dominant hemisphere) * Parietal lobe * Temporal lobe (especially Wernicke's area in the cerebral cortex of the dominant hemisphere) *_References:_* * *See "CSF Vasculature" lecture from Neuroscience.* * *See "Neuro Hx, Physical Exam, and CNs" lecture from Neurology Medicine.* * *Goodman and Fuller (4th ed.), p.1514 ("Middle Cerebral Artery Syndrome")* * *O'Sullivan et al. (7th ed.), p.598 ("Middle Cerebral Artery Syndrome")*

Answer 59

* Contralateral hemiplegia and hemianesthesia * Involves primarily the face (inferior facial muscles) and upper extremity * Contralateral homonymous hemianopsia * Sensory ataxia of contralateral limb(s) * Global aphasia if the dominanant cerebral hemisphere is affected * Apraxia and contralateral spatial neglect if the non-dominant cerebral hemisphere is affected * Spatial neglect may be associated with active contraversive pushing (i.e., lateropulsion) toward the side opposite the side of the brain lesion (i.e., toward the hemiplegic side). *_References:_* * *Goodman and Fuller (4th ed.), p.1514 ("Middle Cerebral Artery Syndrome")* * *O'Sullivan et al. (7th ed.), p.599 (Table 15.3)* * *Purves (6th ed.), p.385 ("Clinical Applications")* * *See coordination and perception lecture from DMNMC II.*

Answer 60

***Anterior cerebral artery (ACA) syndrome*** refers to a collection of signs and symptoms that are associated with an ischemic stroke involving the anterior cerebral artery. _Review:_ In general, the anterior cerebral artery supplies blood to the following areas of the brain: * Medial aspect of the frontal and parietal lobes *_References:_* * *See "CSF Vasculature" lecture from Neuroscience.* * *Goodman and Fuller (4th ed.), p.1514 ("Anterior Cerebral Artery Syndrome")* * *O'Sullivan et al. (7th ed.), pp.597-598 ("Anterior Cerebral Artery Syndrome")*

Answer 61

* Contralateral hemiplegia and hemianesthesia * Involves primarily the lower extremity * Abulia (aka, akinetic mutism), or a delay in verbal and motor response * Slowness, lack of spontaneity, motor inaction * Urinary incontinence * Apraxia * Problems with imitation and bimanual tasks *_References:_* * *Goodman and Fuller (4th ed.), p.1514 ("Anterior Cerebral Artery Syndrome")* * *O'Sullivan et al. (7th ed.), p.599 (Table 15.2)*

Answer 62

* Motor recovery is slowest and least for those that are the most severely affected post-stroke. * Motor recovery is fastest for those that are mildly affected post-stroke. * The greater the number of impairments post-stroke, the less likely individuals will experience functional recovery. * Most recovery occurs within 3 months post-stroke. _Note:_ Compared with MCA syndrome, ACA syndrome has a more favorable prognosis (i.e., minimal loss of neurological function, faster and more complete recovery) due to the collateral blood flow from the anterior communicating artery that can compensate for occlusions of the anterior cerebral artery. The anterior communicating artery connects the right and left anterior cerebral arteries (\*from Goodman and Fuller [4th ed.], p.1514; see also lecture on cerebral vasculature from Neuroscience [slides 59, 68]). *_Reference:_* * *See stroke lecture from DMNMC II.*

Answer 63

* Chronic stroke (i.e., greater than 6 months post-stroke) * _Recommendation:_ Moderate to high-intensity gait training or virtual reality-based gait training to improve walking speed * _Note:_ Body-weight supported treadmill training and robotic-assisted training will NOT improve walking speed. *_Reference:_* * *JNPT: Clinical Practice Guidelines (2020) to Improve Locomotor Function Following Chronic Stroke, Incomplete Spinal Cord Injury, and Brain Injury*

Answer 64

* _Early warning signs of a stroke, and response (\*mnemonic is "Be Fast"):_ * _B:_ *Balance*. Unexplained dizziness, unsteadiness, or sudden falls * _E:_ *Eyes*. Sudden dimness or loss of vision, particularly in one eye * _F:_ *Face*. Sudden weakness or numbness of the face (e.g., asymmetrical smile due unilateral facial droop) * _A:_ *Arm*. Sudden weakness or numbness of the arm (e.g., downward drifting of the arm when attempting to hold the arm in the raised position) * _Note:_ The legs may also present with sudden weakness or numbness. * _S:_ *Speech*. Sudden difficulty speaking or understanding speech * _T:_ *Time*. Call 911 so that the individual can get immediate medical care. *_Reference:_* * *Goodman and Fuller (4th ed.), p.1511, Box 32-2*

Answer 65

***Apraxia*** refers to the loss or impairment of motor planning of purposeful movements (e.g., shaking hands, kicking a ball) that cannot be accounted for by any other reason (e.g., impaired strength, coordination, sensation, tone, cognitive function, communication, or uncooperativeness). ***Agnosia*** refers to the inability to recognize stimuli for what it is and ascribing meaning or significance to particular sensory experiences. Agnosia is present in the absence of disease involving the anatomic and neural structures involved in transduction, transmission, and perception of those stimuli. *_References:_* * *Nolan, p.38, 40* * *O’Sullivan et al. (7th ed.), p.1213* * *See also Youtube video, "Apraxia & Neglect - Draw it to Know it Medical & Biological Sciences" (https://www.youtube.com/watch?v=MhS6WUl5wZE)*

Answer 66

A visual field deficit describes sensory loss restricted to one or more quadrants of the visual field and arises from damage to the primary visual pathway. Visual field deficits can be identified using the confrontation test (\*see "CN II - Special Tests" flashcard). In contrast, spatial neglect describes a failure to report, respond, or orient to stimuli in the space opposite the side of the brain lesion in the absence of sensory or motor deficits. Spatial neglect is thought to be due to lesions along the visual-spatial pathways in the brain. Spatial neglect can be identified through various functional tests and clinical assessment tools. *_References:_* * *BMJ Journal, Journal of Neurology, Neurosurgery, and Psychiatry: Hemianopia and visual neglect (https://jnnp.bmj.com/content/67/5/565)* * *See lecture on coordination and perception from DMNMC II.* * *See lecture on higher cognitive functions from Neuroscience.*

Answer 67

* _C5:_ Anterior deltoid region * _C6:_ Thumb * _C7:_ Middle finger * _C8:_ Ulnar aspect of forearm * _T1:_ Medial aspect of upper arm *_Reference:_* * *See neuroscreening lecture from ECS I.*

Answer 68

* **_L2:_** Proximal aspect of the anterior thigh * **_L3:_** Middle of the anterior thigh to the medial aspect of the knee * **_L4:_** Medial aspect of the lower leg * **_L5:_** Proximal aspect of the lateral lower leg, or the dorsum of foot between the great toe and second toe * **_S1:_** Lateral surface of the foot *_Reference:_* * *See neuroscreening lecture from ECS I.*

Answer 69

***Spinal cord injury (SCI)*** refers to either a traumatic or nontraumatic insult to the spinal cord that results in a change, either temporary or permanent, in its normal motor, sensory, or autonomic function. The level of the SCI is determined based on the neurological level of injury. The **neurological level of injury** is the most caudal level of the spinal cord with normal motor and sensory function on both the left and right sides of the body. A patient with a spinal cord injury can present with a loss of sensation or motor function below the neurological level of injury. * _Example:_ A patient who is determined to have a C6 spinal cord injury will have neurological deficits below the spinal cord level of C6. **Complete SCIs** are characterized by the absence of sensory and motor function in the lowest sacral segments (S4 and S5), with no sacral sparing. * The neurological levels of injury for complete SCIs that result in tetraplegia (aka, quadriplegia) are usually between C1-T1. Patients with spinal cord injuries at C4 or higher will require mechanical ventilation due to inadequate or absent innervation of the diaphragm as well as absent innervation of the muscles of active (forced) expiration (i.e., abdominals and intercostals). * _Muscles of inspiration:_ * \*\*Diaphragm\*\* * _Action:_ Vertical descent of the diaphragm, resulting in (1) an increase in the superior-inferior diameter of the thoracic cage as well as (2) elevation of the lower ribs * _Peripheral innervation:_ Phrenic nerve * _Segmental innervation:_ C3, C4, and C5 spinal nerves * External intercostals and interchondral part of the internal intercostals * _Action:_ Elevation of the ribs * _Peripheral innervation:_ Adjacent intercostal nerve * _Segmental innervation:_ T1-T12 spinal nerves * _Muscles of active (forced) expiration:_ * Internal intercostals (except the interchondral part) * _Action:_ Drawing together of the ribs * _Peripheral innervation:_ Adjacent intercostal nerve * _Segmental innervation:_ T1-T12 spinal nerves * Abdominals * _Action:_ Depress the lower ribs; compress the abdominal contents * _Peripheral innervation:_ Anterior primary rami * _Segmental innervation_ * Rectus abdominus and external obliques: T5-T12 spinal nerves * Transverse abdominus and internal obliques: T7-T12 and L1 spinal nerves * The neurological levels of injury for complete SCIs that result in paraplegia are usually below T1. Although individuals with paraplegia have better respiratory function than people with tetraplegia, they will still have impaired respiratory function due to weak or absent abdominal and intercostal musculature. **Incomplete SCIs** are characterized by the preservation of motor or sensory function below the neurological level of injury that includes sensory or motor function at the lowest sacral segments (S4 and S5), with presence of sacral sparing. Various distinct syndromes have been identified within the category of incomplete SCIs. *_References:_* * *Medscape: Spinal Cord Injuries--Background (https://emedicine.medscape.com/article/793582-overview#a2)* * *Goodman and Fuller (4th ed.), p.1556 ("Definition and Etiologic Factors"), 1561 ("Clinical Manifestations--Level of Injury")* * *O'Sullivan et al. (7th ed.), p.857 ("Designation of Lesion Level"), 858 ("Complete Injuries, Incomplete Injuries, and Zone of Partial Preservation"), 863 ("Pulmonary Impairment;" Table 20.2)* * *For a review of the basics of spinal cord injuries, see YouTube video, "Levels of Spinal Cord Injury" (https://www.youtube.com/watch?v=sZD\_2mtKPrE).* * *For a review of the muscles of inspiration and expiration, see DMCC lecture, "Pulmonary Anatomy and Physiology" (slide 47).*

Answer 70

Classifications of spinal cord injuries can be determined using the American Spinal Cord Injury Association (ASIA) Impairment Scale (or AIS). * **_A (complete SCI):_** * No preservation of motor and sensory functions in the lowest sacral segments (S4-S5) (i.e., no sacral sparing) * **_B (sensory incomplete SCI):_** * Sensory but not motor function is preserved below the neurological level of injury * Includes preservation of only sensory function at the lowest sacral segments (S4-S5) (i.e., sparing of sacral sensation, including light touch or pin prick at S4-S5 or deep anal pressure) * No motor function is preserved more than three levels below the motor level on either side of the body * **Motor level** is defined as the lowest segment representing key muscle function that has a grade of at least 3 (on supine testing), providing that the key muscle functions represented by segments above that motor level are judged to be intact (i.e., graded as a 5) (\*see image below). * **_C (motor incomplete SCI):_** * Motor function is preserved below the neurological level of injury * Less than half of the key muscle functions below the neurological level of injury have a muscle grade greater than or equal to 3 * **_D (motor incomplete SCI):_** * **__**Motor function is preserved below the neurological level of injury * At least half (half or more) of key muscle functions below the neurological level of injury have a muscle grade greater than or equal to 3 * **_E (normal):_** * If tested sensation and motor functions are graded as normal in all segments, and the patient had prior deficits associated with SCI, then the AIS grade is E. Someone without an initial SCI does not receive an AIS grade. *_References:_* * *Goodman and Fuller (4th ed.), p.1561 ("Clinical Manifestations--Level of Injury")* * *O'Sullivan et al. (7th ed.), p.859 ("ASIA Impairment Scale;" Box 20.1)*

Answer 71

***Brown-Séquard syndrome*** refers to a collection of signs and symptoms associated with an incomplete spinal cord injury characterized by damage to one side (i.e., hemisection) of the spinal cord, often due to stabs or gunshot wounds. The most common presentation is the ***Brown-Séquard plus syndrome***, which is characterized by ipsilateral hemiplegia and hemianesthesia with contralateral hemianalgesia. The hallmark signs and symptoms of Brown-Séquard syndrome include (\*see also image below): * _Ipsilateral side of the lesion_ * Lateral corticospinal symptoms: Weakness, brisk reflexes with clonus, positive Babinski sign, spasticity * Dorsal column-medial lemniscal symptoms: Loss of proprioception, vibration, tactile discrimination * Zone of complete loss of sensation due to overlap of anterolateral symptoms with dorsal column-medial lemniscal symptoms (\*see below) * _Contralateral side of the lesion_ * Anterolateral (i.e., spinothalamic) symptoms: Loss of pain and temperature * Initially presents as an ipsilateral loss that occurs several dermatome segments below the neurological level of injury and then is followed by contralateral loss below those dermatome segments *_References:_* * *Purves et al. (6th ed.), pp.217-218, Figure 10.4; 385-386* * *O'Sullivan et al. (7th ed.), p.860 (Brown-Séquard Syndrome)* * *Goodman and Fuller (4th ed.), p.1561 ("Spinal Cord Injury Syndromes"), 1563 (Figure 34.10)* * *Louis et al. (13th ed.) (keyword: Brown-Séquard Syndrome)*

Answer 72

***Central cord syndrome*** is a collection of signs and symptoms associated with an incomplete spinal cord injury characterized by damage to the central aspects of the spinal cord, often due to cervical hyperextension injuries. Central cord syndrome is the most common incomplete SCI syndrome. The hallmark signs and symptoms of central cord syndrome include (\*see image below): * Loss of motor function that is greater in the upper extremities than the lower extremities * Varying degrees of sensory impairment occur but tend to be less severe than motor deficits. *_References:_* * *Goodman and Fuller (4th ed.), p.1563 ("Central Cord Syndrome")* * *O'Sullivan et al. (7th ed.), p.860 ("Central Cord Syndrome")*

Answer 73

***Anterior cord syndrome*** is a collection of signs and symptoms associated with an incomplete spinal cord injury characterized by damage to the anterior and anterolateral aspects of the spinal cord, often due to flexion injuries. The hallmark signs and symptoms of anterior cord syndrome include (\*see image below): * Bilateral loss of motor function * Bilateral loss of pain and temperature sensation *_References:_* * *Goodman and Fuller (4th ed.), p.1563 ("Anterior Cord Syndrome")* * *O'Sullivan et al. (7th ed.), p.860 ("Anterior Cord Syndrome")*

Answer 74

***Posterior cord syndrome*** is a collection of signs and symptoms associated with an incomplete spinal cord injury characterized by damage to the posterior aspect of the spinal cord, which can occur as a result of hyperextension. Posterior cord syndrome is extremely rare. The hallmark signs and symptoms of posterior cord syndrome include (\*see image below): * Preservation of motor function, pain, and light touch sensation * Loss of proprioception, kinesthesia, two point discrimination, stereognosis (aka, tactile agnosia) * Loss of proprioception and kinesthesia can result in severe gait deviations. *_References:_* * *Goodman and Fuller (4th ed.), p.1563 ("Posterior Cord Syndrome")* * *Louis et al. (13th ed.) (keyword: "Posterior Cord Syndrome")*

Answer 75

***Conus medullaris syndrome*** is a collection of signs and symptoms associated with an incomplete spinal cord injury characterized by damage to the very caudal portion of the spinal cord (i.e., the conus medullaris) and its associated lumbosacral spinal nerves within the vertebral canal. The clinical presentation of conus medullaris syndrome reflects a combination of lower motor neuron and upper motor neuron syndromes: * Saddle anesthesia (i.e., loss of sensation at the perineum, the buttocks, and the inner aspect of the thighs) * Areflexic bladder and bowel * Variable degrees of lower extremity weakness and sensory loss *_References:_* * *O'Sullivan et al. (7th ed.), p.860 ("Cauda Equina Syndrome")* * *Louis et al. (13th ed.) (keyword: "Conus Medullaris and Cauda Equina Syndromes")*

Answer 76

***Cauda equina syndrome*** is a collection of signs and symptoms associated with an incomplete spinal cord injury characterized by damage to the lumbosacral spinal nerves within the vertebral canal below the conus medullaris. The hallmark signs and symptoms of cauda equina syndrome reflect lower motor neuron syndrome and include: * Saddle anesthesia (i.e., loss of sensation at the perineum, the buttocks, and the inner aspect of the thighs) * Bladder and bowel dysfunction * Asymmetric lower extremity weakness * Decreased reflexes *_References:_* * *O'Sullivan et al. (7th ed.), p.860 ("Cauda Equina Syndrome")* * *Louis et al. (13th ed.) (keyword: "Conus Medullaris and Cauda Equina Syndromes")*

Answer 77

* **_Spinal shock_** * **__**See "Spinal Shock" flashcard. * **_Autonomic dysreflexia_** * ***Autonomic dysreflexia*** refers to a loss of coordinated autonomic responses to noxious stimuli (e.g., overextended bladder or bowel, kinked catheter, exposure to high heat or excessive cold, pressure sores, constricting clothing or shoes) among patients with spinal cord injuries above T6. * Autonomic dysreflexia is a medical emergency and requires immediate attention! * _Clinical presentation:_ * Sudden and significant (\>20 mm Hg) increase in both systolic and diastolic blood pressure above normal * Normal blood pressure when the neurologic level of injury is above T6 is 90-110 mm Hg systolic and 50-60 mm Hg diastolic. * Profuse sweating and skin flushing above the neurologic level of injury due to vasodilation and subsequent increase in blood flow * Severe pounding headache with chills without fever * Headache may be due to the increase in arterial blood pressure. * Excessive bradycardia * _Interventions:_ * Find and eliminate the cause of the noxious stimulus. * Place the patient in a short-sitting position. * The force of gravity in the upright position will reduce venous return and subsequently decrease cardiac output and arterial blood pressure. * Call the physician or rehab nurse. * **_Orthostatic hypotension_** * ***Orthostatic hypotension*** (aka, *postural orthostatic hypotension*, *postural hypotension*) generally refers to a sudden drop in arterial blood pressure when changing positions, usually moving from supine to an upright position (i.e., sitting or standing). * Orthostatic hypotension is more specifically defined as the following changes in both arterial blood pressure and pulse rate during changes in position (e.g., supine to sitting, sitting to standing): * Decrease in systolic blood pressure of at least 20 mm Hg, _OR_ * Decrease in diastolic blood pressure of at least 10 mm Hg, _AND_ * A 10% to 20% increase in pulse rate (i.e., increase of 15 bpm or more) * Patients with spinal cord injuries (especially higher-level injuries resulting in quadriplegia and paraplegia) are more at risk for orthostatic hypotension due to (1) dysregulation of the baroreceptor reflex secondary to disruption of the autonomic nervous system, and (2) venous pooling in the lower extremities and abdominal viscera secondary to loss of the skeletal muscle pumping action below the level of spinal cord injury (especially during spinal shock). * _Clinical presentation:_ * Dizziness * Lightheadedness * Pallor * Diaphoresis * Blurring or loss of vision * Leg buckling or loss of balance (\*due to non-specific causes) * Syncope ***_(fall risk!)_*** * _Interventions:_ * If a syncope is imminent, immediately assist the patient back into supine with the head of the bed elevated slightly (e.g., 5-20 degrees) and the legs elevated. * Because the imminent syncope places the patient at a high fall risk whether standing or sitting, placing the patient in supine will ensure patient safety until the orthostatic hypotension symptoms have resolved. * Elevating the head of the bed slightly will (1) reduce the effects of positional accommodation of the arterial baroreceptors, and (2) reduce the likelihood of hypovolemia and subsequent supine hypotension by decreasing the amount of diuresis and naturesis associated with the atrial stretch reflex. * Elevating the legs will ensure that the pooled venous blood is assisted back to the heart by gravity, improving venous return and subsequent blood flow to the brain. * Donning abdominal binders or elastic bandage wraps or stockings for the lower extremities—will increase venous pressure, which drives more blood out of the veins into the heart (i.e., increased venous return) * **_Chronic incomplete SCI (i.e., greater than 6 months post-injury)_** * _Recommendation for intervention:_ Moderate to high-intensity gait training or virtual reality-based gait training to improve walking speed * _Note:_ Body-weight supported treadmill training and robotic-assisted training will NOT improve walking speed. *_References:_* * *See lecture on SCI from DMNMC II.* * *Medscape: Autonomic Dysreflexia in Spinal Cord Injury—Overview ([https://emedicine.medscape.com/article/322809-overview](https://emedicine.medscape.com/article/322809-overview))* * *Medscape: Autonomic Dysreflexia in Spinal Cord Injury—Pathophysiology ([https://emedicine.medscape.com/article/322809-overview#a2](https://emedicine.medscape.com/article/322809-overview#a2))* * *See "Specific NPTE Study Topics" Word doc.* * *JNPT: Clinical Practice Guidelines (2020) to Improve Locomotor Function Following Chronic Stroke, Incomplete Spinal Cord Injury, and Brain Injury*

Answer 78

_Most favorable prognosis for ambulation and functional recovery:_ * Brown-Séquard syndrome, or central cord syndrome * AIS D (motor incomplete SCI) _Least favorable prognosis for ambulation and functional recovery:_ * Anterior cord syndrome * AIS A (complete SCI) *_References:_* * *Louis et al. (13th ed.) (keyphrase: "A subset of SCIs has been grouped by their specific clinical features into six clinical syndromes...")* * *See lecture on SCI from DMNMC II.*

Answer 79

***Myasthenia gravis*** (aka, *grave muscle disease*) is a neuromuscular disorder that is characterized by decreased efficiency of impulse transmission across the neuromuscular junction with a subsequent decrease in stimulation of muscle contraction. *_References:_* * *Goodman and Fuller (4th ed.), p.1696 ("Pathogenesis")* * *Vander's (15th ed.), p.263 ("Membrane Excitation: The Neuromuscular Junction"), 284 ("Myasthenia Gravis")*

Answer 80

**_Gender:_** Female **_Age:_** 20-30s **_Past medical history:_** * Thyroid diseases (e.g., hyperthyroidism) * Due to association with autoimmune disruptions of the thyroid gland * Type 1 diabetes mellitus * Due to association with autoimmune disruptions of the pancreas * Autoimmune disorders (e.g., rheumatoid arthritis) *_Reference:_* * *Goodman and Fuller (4th ed.), p.1696 ("Risk Factors")*

Answer 81

The most common cause of myasthenia gravis is the destruction of acetylcholine (ACh)-receptor proteins of the motor end plate as part of an autoimmune response. *_References:_* * *Goodman and Fuller (4th ed.), p.1696 ("Pathogenesis")* * *Vander's (15th ed.), p.263 ("Membrane Excitation: The Neuromuscular Junction"), 284 ("Myasthenia Gravis")*

Answer 82

* Fluctuating weakness and fatigability of skeletal muscles * Repetition of activity or sustained activity causes fatigue, whereas rest restores activity. * In most cases of myasthenia gravis, skeletal muscle weakness is generalized and affects the limb musculature. The fluctuating weakness is also often more noticeable in proximal muscles. * _Cranial nerve involvement:_ * Ptosis due to CN III (oculomotor) nerve involvement * Diplopia due to involvement of CN III, IV, and VI nerves (i.e., the cranial nerves controlling eye movements) * Weakness and fatigability of the muscles of mastication and muscles of facial expression due to involvement of the CN V (trigeminal) and CN VII (facial) nerves, respectively * Dysarthria due to involvement of CN XII (facial) nerve * Dysphagia due to involvement of primarily CN X (vagus) and CN XII (hypoglossal) nerves *_Reference:_* * *Goodman and Fuller (4th ed.), p.1697 ("Clinical Manifestations")*

Answer 83

Myasthenia gravis follows a slowly progressive course that is characterized by periods of remissions and exacerbations. Remissions are rarely complete or permanent. *_Reference:_* * *Goodman and Fuller (4th ed.), pp.1697-1698 ("Prognosis")*

Answer 84

The ***ice test*** for myasthenia gravis (\*see also image below): * A pack of ice is placed over the eye demonstrating ptosis for 1 to 2 minutes. * Resolution or improvement in the ptosis is considered positive and highly specific for myasthenia gravis. * It is unclear why decreased temperature reduces ptosis, but a proposed hypothesis is that decreased temperatures improves neuromusclar transmission. *_References:_* * *Louis et al. (13th ed.) (keyword: ice test)* * *SpringerLink: Ice Pack Test for Myasthenia Gravis (https://link.springer.com/referenceworkentry/10.1007/978-3-642-35951-4\_1285-1)* * *BMJ: Can myasthenia gravis...? (https://pmj.bmj.com/content/76/893/162)*

Answer 85

* ***Monitor for signs and symptoms of an impending myasthenic crisis.*** * A myasthenic crisis is a **_medical emergency_** requiring attention to life-endangering weakening of the respiratory muscles and requires ventilatory assistance. * _Clinical presentation of myasthenic crisis:_ * Increasing muscle weakness * Respiratory distress * Difficulty while talking, chewing, or swallowing * ***Higher risk for developing osteoporosis due to long-term use of corticosteroids (e.g., prednisone) for immunosuppression*** *_Reference:_* * *Goodman and Fuller (4th ed.), p.1698 ("Special Implications for the Therapist")*

Answer 86

***Traumatic brain injury (TBI)*** refers to damage from an external physical force that impairs brain function. *_Reference:_* * *Goodman and Fuller (4th ed.), p.1535 ("Overview and Definition")*

Answer 87

In addition to upper motor neuron signs and symptoms (e.g., paresis, hypertonicity), patients with TBIs will demonstrate: * Impaired cognitive function * _Examples:_ Deficits in arousal, attention, concentration, memory, learning, and executive functions (e.g., problem solving, decision making, abstract reasoning, processing speed) * Impaired neurobehavioral functions * _Examples:_ Low frustration tolerance, agitation, disinhibition, apathy, emotional lability, mental inflexibility, physical and verbal aggression, impulsivity, and irritability * Impaired communication * _Examples:_ Disorganized and tangential oral or written communication, imprecise language, word-retrieval difficulties, disinhibited and socially inappropriate language * Increased risk for developing heterotopic ossification (HO) * The cause and pathogenesis of HO is unknown but is associated with trauma around a joint, immobility, and increased tone. * Onset of HO is usually 4 to 12 weeks after the traumatic brain injury, and it is first detected with a loss of range of motion. Local tenderness and a palpable mass eventually can be detected, and there can be erythema, swelling, and pain with movement. *_References:_* * *O'Sullivan et al. (7th ed.), p.820 ("Body Structure/Function Impairments")* * *For more about executive functions, see lecture on higher cognitive functions from Neuroscience.* * *Goodman and Fuller (4th ed.), p.1545 ("Heterotopic Ossification")*

Answer 88

* If possible, treat patients in an environment that is less distracting and visually stimulating to compensate for cognitive, neurobehavioral, and communication deficits. * To control and ensure adequate drainage of cerebral venous blood flow, patients who are resting in bed should maintaining the head in a neutral, non-rotated position with the head of the bed elevated 20 to 40-degrees. * **_Glascow Coma Scale (GCS)_** * The GCS is a clinical tool that helps to define and classify the severity of traumatic brain injuries based on motor response, verbal response, and eye opening. * Traumatic brain injury is generally categorized as severe, moderate, or mild. * _Severe TBI:_ Less than or equal to 8 * _Moderate TBI:_ 9-12 * _Mild TBI:_ 13-15 * **_Ranchos Los Amigos Scale of Levels of Cognitive Functioning (LOCF)_** * The Ranchos Los Amigos Scale of LOCF is a descriptive tool used to examine cognitive and behavioral recovery in individuals with TBI as they emerge from coma. This scale does not address specific cognitive deficits but is useful for communicating general cognitive or behavioral status and for treatment planning. * **_Level 1:_ *No response***. Patient appears to be in a deep sleep and is completely unresponsive to any stimuli. * **_Level 2:_ *Generalized response*.** Patient reacts inconsistently and nonpurposefully to stimuli in a nonspecific manner. * **_Level 3:_ *Localized response*.** Patient reacts specifically but inconsistently to stimuli. * **_Level 4:_ *Confused-Agitated*.** Patient is in a heightened state of activity. Behavior is bizarre and nonpurposeful relative to the immediate environment. * **_Level 5:_ *Confused-Inappropriate*.** Patient is able to respond to simple commands fairly consistently. Patient is highly distractible, verbalization is often inappropriate, memory is severely impaired, and patient often shows inappropriate use of objects. * **_Level 6:_ *Confused-Appropriate*.** Patient shows goal-directed behavior but is dependent on external input or direction. * **_Level 7:_ *Automatic-Appropriate*.** Patient appears appropriate and oriented within the hospital and home settings; goes through daily routine automatically but frequently robot-like. * **_Level 8:_ *Purposeful-Appropriate*.** Patient is able to recall and integrate past and recent events and is aware of and responsive to environment. * **_Chronic TBI (i.e., greater than 6 months post-injury)_** * _Recommendation for intervention:_ Moderate to high-intensity gait training or virtual reality-based gait training to improve walking speed * _Note:_ Body-weight supported treadmill training and robotic-assisted training will NOT improve walking speed. *_References:_* * *Goodman and Fuller (4th ed.), pp.1554-1555 ("Special Implications for the Therapist")* * *O'Sullivan et al. (7th ed.), p.822 ("Glascow Coma Scale"), 827 (Box 19.3)* * *JNPT: Clinical Practice Guidelines (2020) to Improve Locomotor Function Following Chronic Stroke, Incomplete Spinal Cord Injury, and Brain Injury*

Answer 89

***Sciatica*** refers to pain radiating from the lower back into the buttock and down the posterior or lateral aspect of the thigh into the leg. Sciatica is often caused by a herniated lumbar intervertebral disc that compresses and compromises the L5 or S1 component of the sciatic nerve. * _Note:_ Posterior or posterolateral protrusions at the L4-L5 and L5-S1 levels are most common types of herniated intervertebral discs (\*from Kisner and Colby [7th ed.], p.446 ["Variability of symptoms"]). The general rule is that when an herniated intervertebral disc protrudes posterolaterally, it usually compresses the spinal nerve numbered one inferior to the herniated disc. For example, a L4–L5 herniated intervertebral disc compresses the L5 spinal nerve, and a L5-S1 herniated intervertebral disc compresses the S1 spinal nerve (\*from Moore et al. [8th ed.], p.109). * See also Netter Plate 161 (PDF p. 187) for a visual example of a herniated intervertebral disc and its effect on nearby spinal nerves. * Posterolateral protrusions at the lumbar spine are usually treated with lumbar extension exercises to help mechanically reduce the protrusion and cause centralization of the pain (\*from Kisner and Colby [7th ed.], p.447 ["Objective Clinical Findings in the Lumbar Spine"]). Any maneuver that stretches the sciatic nerve, such as extending the knee (e.g., sitting knee extension) or flexing the thigh with the knee extended (e.g., straight leg-raise test in supine), generally produces or exacerbates sciatica. * _Straight-leg raise test (\*see image below)_ * _Procedure:_ With the patient in supine, passively flex the hip of the affected lower extremity while keeping the knee extended. * _Positive results for sciatica:_ * Neurological symptoms (e.g., burning, tingling, shooting) that occur below the gluteal fold and between 30-50° of hip flexion * Neurological symptoms become worse or more peripheral (i.e., below the gluteal cleft) when passively dorsiflexing the ankle of the affected lower extremity at the patient's limit of the straight-leg raise motion. *_References:_* * *Moore et al. (8th ed.), p.109* * *See ECS I lecture, "Neuroscreening" (p.15)*

Answer 90

The ***Modified Ashworth Scale (MAS)*** is an assessment tool used to examine spasticity. The MAS assigns a subjective rating of the amount of resistance or tone perceived by the examiner as a limb is moved through its full range of motion. * 0 = No increase in tone * 1 = Slight increase in muscle tone manifested by a catch and release or by minimal resistance at the end of the range of motion when the affected part(s) is moved in flexion or extension * 1+ = Slight increase in muscle tone, manifested by a catch, followed by minimal resistance throughout the remainder (less than half) of the ROM * 2 = More marked increase in tone through most of the ROM, but affected part(s) easily moved * 3 = Considerable increase in muscle tone, passive movement difficult * 4 = Affected part(s) rigid in flexion or extension *_Reference:_* * *See DMNMC I lecture, "Assessment of Muscle Tone" PDF (pp.12, 14-15).*

Answer 91

***Carpal tunnel syndrome (CTS)*** (aka, *median neuropathy*, *tardy median palsy*) refers to compression of the median nerve within the carpal tunnel in the wrist that results in pain, paresthesia, numbness, and weakness in the distribution of the median nerve. * The **carpal tunne**l is a osseofibrous passageway at the wrist through which the median nerve, flexor pollicis longus tendon, flexor digitorum superficialis tendons, and flexor digitorum profundus tendons pass through (\*see image below). The hallmark of the carpal tunnel is that it is cylindrical and inelastic. None of the sides of the tunnel yields to expansion of the fluid or structures within. Change within the tunnel is the basis of study related to the etiology of carpal tunnel, but the matrix of possible causes proves to be complex and not fully understood at this time. *_Reference:_* * *Goodman and Fuller (4th ed.), p.1668 ("Median Neuropathy: Carpal Tunnel Syndrome"), 1668-1669 ("Etiology")*

Answer 92

* Sensory symptoms in the median nerve distribution (\*see image below) * Nocturnal pain * Pain may be located distally in the forearm or wrist and radiate into the thumb, index, and middle fingers. Pain may also radiate into the arm, shoulder, and neck. * Decreased two-point discrimination, vibration, pressure, and light touch * Muscle atrophy and motor symptoms can develop in advanced cases of CTS. *_Reference:_* * *Goodman and Fuller (4th ed.), p.1670 ("Clinical Manifestations")*

Answer 93

* **Tinel's sign** * _Procedure:_ The examiner taps over the carpal tunnel at the wrist. * _Interpretation:_ A positive result is characterized by tingling or paresthesia into the thumb, index finger (forefinger), and middle and lateral half of the ring finger (median nerve distribution). The tingling or paresthesia is felt distal to the point of pressure. * Indicates carpal tunnel syndrome * **Nerve conduction velocity test** * A nerve conduction velocity test (\*see image below) measures the speed at which an electrical stimulus passes through the nerves. **Latency**, or the time it takes for the electrical impulse to travel from the stimulation site to the recording site, is measured. Increased latency is associated with conditions involving damage to nerves (e.g., carpal tunnel syndrome). *_References:_* * *Magee (6th ed.), p.474 ("Tinel Sign [at the Wrist]")* * *JCDR: The Comparision of the Motor Nerve Conduction Velocity (https://www.jcdr.net/article\_fulltext.asp?id=1195#:~:text=INTRODUCTION.%20The%20nerve%20conduction%20study%20%28NCS%29%20is%20a,motor%20and%20sensory%20nerves%20of%20the%20human%20body.)*

Answer 94

***Cerebral palsy (CP)*** is a non-progressive lesion of the brain occurring prior to 2 years of age resulting in a disorder of posture and movement. Cerebral palsy may be accompanied by impairment of the skeletal system, including hip dislocation and scoliosis; oral motor and gastrointestinal (GI) function, including speech, feeding, and GI motility; as well as sensory disturbances, including vision, visual perception, and hearing. Primitive motor reflexes may also be present (e.g., asymmetric tonic neck reflex, symmetric tonic neck reflex). * _Asymmetric tonic neck reflex (ATNR):_ With the head turning to one side, the arm and leg on the same side extend while the arm and leg on the oppo-site side flex. This posture resembles a fencing position and prevents the child from bringing the left hand to her mouth for exploration and self-feeding (\*see p.1581, Figure 35-3). * _Symmetric tonic neck reflex (STNR):_ When the head and neck are extended, the arms extend; flexion usually predominates in the lower extremities. Flexion of the head and neck causes flexion in the upper extremities and extension in the lower extremities (\*see p.1582, Figure 35-4). The most common type of cerebral palsy is **spastic cerebral palsy**, particularly *spastic quadriplegia* (i.e., muscle spasticity affecting the extremities, trunk, head, and neck) and *spastic diplegia* (i.e., muscle spasticity of the lower extremities more than the upper extremities). *_References:_* * *Goodman and Fuller (4th ed.), p.1576 ("Overview")* * *See also DMNMC II lecture on cerebral palsy (p.1).*

Answer 95

***Parkinson's disease (PD)*** (aka, *idiopathic parkinsonism*) refers to a chronic progressive neurodegenerative disease of the central nervous system (specifically the basal ganglia) that is characterized by resting tremor, bradykinesia or akinesia, rigidity, postural instability, and shuffling and freezing gait. * **Resting tremor** refers to involuntary, rhythmic, and slow shaking of a limb at rest (i.e., the limb is in a relaxed position). In PD, resting tremor initially manifests as a rhythmic, back-and-forth motion of the thumb and finger, referred to as the *pill-rolling tremor*. Resting tremor can become worse with stress situations (e.g., constipation). * **Rigidity** refers to heightened resistance to passive movement of the limb that is equal in all directions and is velocity-independent. Rigidity can present as a jerky response (tremor under rigidity), known as *cogwheel rigidity*, or as a slow and sustained resistance, known as *lead-pipe rigidity*. * **Bradykinesia** refers to slowness of movement, whereas **akinesia** in PD refers to an reduced amount of natural and automatic movements (e.g., eye blinks that results in an expressionless and mask-like face). * **Postural instability** refers to a reduced ability to maintain balance when experiencing a perturbation. * Gait in PD is characterized by a flexed, stooped posture; short, shuffling steps that can be exacerbated with festination; and freezing gait. * **Festination** refers to a phenomenon characterized by decreased step length and increased cadence (aka, step rate). Festination commonly occurs when the patient is attempting to stop or change direction. * **Freezing gait** refers to the sudden and transient cessation of movement in the middle of the gait cycle, as if the foot is stuck to the floor. Freezing gait commonly occurs with gait initiation, turning, or gait termination. Visual cues such as markers on the floor appear to help patients overcome moments of freezing during gait. \*_Note:_ Anosmia (i.e., the loss of the sense of smell) is characteristic of early-onset Parkinson's disease (\*see CN I flashcard). *_References:_* * *Goodman and Fuller (4th ed.), p.1494 ("Overview and Definition"), 1497-1498 ("Clinical Manifestations")* * *See Neurology Medicine lecture on Parkinson's disease.*

Answer 96

* **Hip flexion** * _Iliopsoas muscle group_ * _Psoas major:_ * _Peripheral innervation:_ Anterior primary rami of L1, L2, and L3 spinal nerves * _Segmental innervation:_ L1, L2, L3, and L4 spinal nerves * _Iliacus:_ * _Peripheral innervation:_ Femoral nerve * _Segemental innervation:_ L1, L2, L3, L4 spinal nerves * **Hip extension** * _Gluteus maximus_ * _Peripheral innervation:_ Inferior gluteal nerve * _Segmental innervation:_ L5, S1, and S2 spinal nerves * **Hip ABduction** * _Gluteus medius and gluteus minimus_ * _Peripheral innervation:_ Superior gluteal nerve * _Segmental innervation:_ L4, L5, and S1 spinal nerves * **Knee flexion** * ****_Hamstrings muscle group_ * _Semimembranosus_ * _Peripheral innervation:_ Tibial nerve * _Segmental innervation:_ L4, L5, S1, and S2 spinal nerves * _Semitendinosus_ * _Peripheral innervation:_ Tibial nerve * _Segmental innervation:_ L4, L5, S1, and S2 spinal nerves * _Biceps femoris (long head)_ * _Peripheral innervation:_ Tibial nerve * _Segmental innervation:_ L5, S1, S2, and S3 spinal nerves * _Biceps femoris (short head)_ * _Peripheral innervation:_ Common fibular (peroneal) nerve * _Segmental innervation:_ L5, S1, and S2 spinal nerves * **Knee extension** * _Quadriceps femoris muscle group: Rectus femoris, vastus medialis, vastus lateralis, vastus intermedius_ * _Peripheral innervation:_ Femoral nerve * _Segmental innervation:_ L2, L3, and L4 spinal nerves * **Ankle dorsiflexion** * _Tibialis anterior, extensor hallucis longus, extensor digitorum longus_ * ****_Peripheral innervation:_ Deep fibular (peroneal) branch of the common fibular nerve * _Segmental innervation:_ L4, L5, and S1 spinal nerves * **Ankle plantarflexion** * _Triceps surae muscle group_ * _Gastrocnemius_ * _Peripheral innervation:_ Tibial nerve * _Segmental innervation:_ S1 and S2 spinal nerves * _Soleus_ * _Peripheral innervation:_ Tibial nerve * _Segmental innervation:_ L5, S1, and S2 spinal nerves * _Tibialis posterior_ * _Peripheral innervation:_ Tibial nerve * _Segmental innervation:_ L4, L5, and S1 spinal nerves * **Ankle eversion** * ****_Fibularis longus and brevis_ * _Peripheral innervation:_ Superficial fibular (peroneal) branch of the common fibular nerve * _Segmental innervation:_ L4, L5, and S1 spinal nerves**** * **Ankle inversion** * _Tibialis posterior (\*see above)_ * _Flexor digitorum longus; flexor hallucis longus_ * ****_Peripheral innervation:_ Tibial nerve * _Segmental innervation:_ L5, S1, and S2 spinal nerves

Answer 97

* **Shoulder elevation (shoulder shrug)** * ****_Upper trapezius_ * _Peripheral innervation:_ Anterior primary rami of cervical spinal nerves; CN XI (spinal accessory) * _Segmental innervation:_ C2, C3, and C4 spinal nerves; CN XI (spinal accessory) * _Levator scapulae_ * _Peripheral innervation:_ Anterior primary rami of cervical spinal nerves; dorsal scapular nerve * _Segmental innervation:_ C3 and C4 spinal nerves; C4 and C5 spinal nerves * **Shoulder ABduction** * ****_Deltoid muscle group (anterior, middle, posterior)_ * _Peripheral innervation:_ Axillary nerve * _Segmental innervation:_ C5 and C6 spinal nerves**** * _Supraspinatus_ * ****_Peripheral innervation:_ Suprascapular nerve * _Segmental innervation:_ C4, C5, and C6 spinal nerves * **Shoulder flexion** * _Anterior deltoid (\*see above)_ * _Coracobrachialis_ * _Peripheral innervation:_ Musculocutaneous nerve * _Segmental innervation:_ C6 and C7 spinal nerves * _Biceps brachii_ * _Peripheral innervation:_ Musculocutaneous nerve * _Segmental innervation:_ C5 and C6 spinal nerves******** * **Shoulder extension** * **Shoulder external rotation** * **Shoulder internal rotation** * **Elbow flexion** * **Elbow extension** * **Wrist extension** * **Wrist flexion** * **Finger extension** * **Finger flexion**