Chapter 8 : Lession of the Spinal Cord (4) Flashcards
Neuropathologic examination of the spinal cord reveals two lesions labeled A and B. Lesion A is restricted to five segments.
1. The result of lesion A is best described as
(A) bilateral arm dystaxia with dysdiadochokinesia
(B) spastic paresis of the legs
(C) flaccid paralysis of the upper extremities
(D) loss of pain and temperature sensation below the lesion
(E) urinary and fecal incontinence
1–C. Lesion A involves degeneration of the ventral horns bilaterally at midcervical levels, resulting in flaccid paralysis in the upper extremities.
- The result of lesion B is best described as
(A) dyssynergia of movements affecting both arms and legs
(B) flaccid paralysis of the upper extremities
(C) impaired two-point tactile discrimination in both arms
(D) spastic paresis affecting primarily the muscles distal to the knee joint
(E) bilateral apallesthesia
2–D. Lesion B involves degeneration of the lateral corticospinal tracts bilaterally, resulting in spastic paresis of the lower extremities and primarily affecting the muscles distal to the knee. Spastic paresis of the upper extremities is masked by flaccid paralysis resulting from lesion A. Apallesthesia is the inability to perceive a vibrating tuning fork
3–E. Lesions A and B are the result of amyotrophic lateral sclerosis, a pure motor disease.
- Neurologic examination reveals an extensor plantar reflex on the left side, hyperreflexia on the left side, a loss of pain and temperature sensation on the right side, and ptosis and miosis on the left side. A lesion that causes this constellation of deficits would most likely be found in the
(A) paracentral lobule, left side
(B) crus cerebri, right side
(C) dorsolateral medulla, left side
(D) cervical spinal cord
(E) lumbar spinal cord
4–D. A lesion of the cervical spinal cord could result in ipsilateral Horner syndrome, ipsilateralspastic paresis, and contralateral loss of pain and temperature sensation. Horner syndrome is always manifested on the ipsilateral side. This lesion produces a classic Brown-Séquard syndrome.
- A 50-year-old woman complains of clumsiness in her hands while working in the kitchen: she recently burned her hands on the stove without experiencing any pain. Neurologic examination reveals bilateral weakness of the shoulder girdles, arms, and hands, as well as a loss of pain and temperature sensation covering the shoulder and upper extremity in a cape-like distribution. Severe atrophy is present in the intrinsic muscles of the hands. The most likely diagnosis is
(A) amyotrophic lateral sclerosis
(B) subacute combined degeneration
(C) Werdnig-Hoffmann disease
(D) syringomyelia
(E) tabes dorsalis
5–D. Syringomyelia is a cavitation of the spinal cord most commonly seen in the cervicothoracic segments. This condition results in bilateral loss of pain and temperature sensation in a cape-like distribution as well as wasting of the intrinsic muscles of the hands. Amyotrophic lateral sclerosis is a pure motor syndrome; subacute combined degeneration includes both sensory and motor deficits; Werdnig-Hoffmann disease is a pure motor disease; and tabes dorsalis is a pure sensory syndrome (neurosyphilis).
- A 50-year-old man has a 2-year history of progressive muscle weakness in all extremities, with severe muscle atrophy and reduced MSRs in both legs. In his arms, the muscle atrophy is less pronounced and the MSRs are exaggerated.
Which of the following types of neuronal degeneration would postmortem examination most likely show?
(A) Loss of Purkinje cells
(B) Loss of neurons from the globus pallidus
(C) Loss of neurons from the paracentral lobule and from the anterior horns of the spinal cord
(D) Demyelination of axons in the posterior and lateral columns
(E) Demyelination of axons in the posterior limb of the internal capsule
6–C. Amyotrophic lateral sclerosis affects both the upper and lower motor neurons. It is also referred to as motor systems disease. A loss of Purkinje cells as seen in cerebellar cortical atrophy (cerebello-olivary atrophy) results in cerebellar signs. Cell loss in the globus pallidus and putamen is seen in Wilson disease (hepatolenticular degeneration). Demyelination of axons in the posterior and lateral columns is seen in subacute combined degeneration. Demyelination of axons in the
posterior limb of the internal capsule results in contralateral spastic hemiparesis.
- Transection of the spinothalamic tract results in
(A) Loss of pain and temperature sensation
(B) Complete flaccid paralysis
(C) Spastic paresis
(D) Cerebellar incoordination
(E) Areflexia
7–A. Transection of the spinothalamic tract results in loss of pain and temperature sensations, starting one segment below the lesion. Ventral horn destruction results in complete flaccid paralysis and areflexia at the level of the lesion. Corticospinal tract transection results in spastic paresis below the lesion. Dorsal spino cerebellar tract and ventral spinocerebellar tract transection results in cerebellar incoordination.
- Which of the following is a characteristic of Lou Gehrig disease?
(A) Loss of tactile discrimination
(B) Loss of vibratory sensation
(C) Dorsal root irritation
(D) Progressive bulbar palsy
(E) Stereoanesthesia
8–D. Progressive bulbar palsy is a lower motor neuron component of amyotrophic lateral sclerosis, or Lou Gehrig disease. Disease characteristics are muscle weakness and wasting without sensory deficits. Loss of tactile discrimination, loss of vibratory sensation, stereoanesthesia, and dorsal root irritation are all sensory deficits found in dorsal column syndrome.
- Clasp-knife spasticity results from a lesion in the
(A) Ventral corticospinal tract
(B) Ventral spinothalamic tract
(C) Lateral corticospinal tract
(D) Dorsal spinocerebellar tract
(E) Lateral spinothalamic tract
9–C. Clasp-knife spasticity is an ipsilateral motor deficit found below a lesion of the lateral corticospinaltract. It is characterized by initial but fading resistance of a briskly moved joint.
- Which of the following syndromes is associated with an absent Achilles tendon reflex?
(A) Filum terminale
(B) Cauda equina
(C) Conus medullaris
(D) Epicomus
(E) Syringomyelia
10–D. Epicomus syndrome involves segments L4 to S2 and results in loss of voluntary control of the bladder and rectum, motor disability, and an absent Achilles tendon reflex.
- An example of a peripheral nervous system lesion is
(A) Guillain-Barré syndrome
(B) Charcot-Marie-Tooth disease
(C) Friedreich ataxia
(D) Lou Gehrig disease
(E) Brown-Séquard syndrome
11-A. Acute idiopathic polyneuritis, or Guillain-Barré syndrome, is a peripheral nervous system lesion. It typically follows an infectious illness and results from a cell-mediated immunologic reaction.
- A patient has the ability to stand with open eyes but falls with closed eyes. A lesion of which pathway is likely responsible for this symptom?
(A) Ventral spinothalamic tract
(B) Dorsal spinocerebellar tract
(C) Lateral spinothalamic tract
(D) Ventral spinocerebellar tract
(E) Dorsal column syndrome
12-E. Dorsal column syndrome results in a sensory deficit known as sensory dystaxia, or Romberg sign. Patients are Romberg positive when they are able to stand with the eyes open but fall with the eyes closed.
The response options for items 13 to 18 are the same. Select one answer for each item in the set.
(A) Amyotrophic lateral sclerosis
(B) Cauda equina syndrome
(C) Cervical spondylosis
(D) Friedreich ataxia
(E) Guillain-Barré syndrome
(F) Multiple sclerosis
(G) Subacute combined degeneration
(H) Tabes dorsalis
(I) Werdnig-Hoffmann disease
Match each statement below with the syndrome that corresponds best to it.
- A pure lower motor neuron disease
13–I. Werdnig-Hoffmann disease is a heredofamilial degenerative disease of infants that affects only LMNs.
The response options for items 13 to 18 are the same. Select one answer for each item in the set.
(A) Amyotrophic lateral sclerosis
(B) Cauda equina syndrome
(C) Cervical spondylosis
(D) Friedreich ataxia
(E) Guillain-Barré syndrome
(F) Multiple sclerosis
(G) Subacute combined degeneration
(H) Tabes dorsalis
(I) Werdnig-Hoffmann disease
Match each statement below with the syndrome that corresponds best to it.
I
- Elevated CSF protein with a normal CSF cell count
14–E. Guillain-Barré syndrome is characterized by elevated CSF protein with normal CSF cell count (albuminocytologic dissociation).
The response options for items 13 to 18 are the same. Select one answer for each item in the set.
(A) Amyotrophic lateral sclerosis
(B) Cauda equina syndrome
(C) Cervical spondylosis
(D) Friedreich ataxia
(E) Guillain-Barré syndrome
(F) Multiple sclerosis
(G) Subacute combined degeneration
(H) Tabes dorsalis
(I) Werdnig-Hoffmann disease
Match each statement below with the syndrome that corresponds best to it.
- Characterized by asymmetric lesions found in the white matter of cervical segments
15–F. Multiple sclerosis is characterized by asymmetric lesions frequently found in the white matter of cervical segments.
19–C. A neurologic manifestation of vitamin B12 deficiency is subacute combined degeneration. There is no involvement of LMNs.
20–A. Lesion A shows the territory of infarction resulting from occlusion of the ventral (anterior) spinal artery.
21–D. A spinal cord hemisection (Brown-Séquard syndrome) on the right side results in a loss of vibration sensation on the right side and a loss of pain and temperature sensation on the left side (dissociated sensory loss).
22–A. Total occlusion of the ventral spinal artery, involving five cervical segments, results in infarction of the ventral two-thirds of the spinal cord and interrupts both lateral spinothalamic tracts. The patient would have a loss of pain and temperature sensation caudal to the lesion.
23–B. Lesion B shows a cervical syringomyelic lesion involving the ventral white commissure, both ventral horns, and the right corticospinal tract. The patient would have a bilateral loss of pain and temperature sensation in the hands, muscle wasting in both hands, and a spastic paresis on the right side.
24–A. In lesion A, both lateral and ventral funiculi have been infarcted by arterial occlusion. Bilateral destruction of the lateral corticospinal tracts at upper cervical levels results in quadriplegia (spastic paresis in upper and lower extremities). Bilateral destruction of the ventrolateral quadrants results in urinary and fecal incontinence
25–C. In lesion C, subacute combined degeneration, there is no involvement of LMNs, hence no flaccid paralysis, muscle atrophy, or fasciculations.
26–C. In lesion C, subacute combined degeneration, there is symmetric degeneration of the white matter, both in the dorsal columns (fasciculi gracilis) and in the lateral funiculi (corticospinal tracts). In this degenerative disease, both the myelin sheaths and the axis cylinders are involved. Subacute combined degeneration is classified under nutritional diseases (in this case a
vitamin B12 neuropathy). In true demyelinative diseases (e.g., multiple sclerosis), the myelin sheaths are involved but the axis cylinders and nerve cells are relatively spared.
