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MindMap Gallery Clinical Medicine Undergraduate Neurology Section 1 Central Nervous System
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Clinical Medicine Undergraduate Neurology Section 1 Central Nervous System
Undergraduate Clinical Medicine Neurology Central Nervous System, which summarizes the cerebral hemispheres, internal capsule, basal ganglia/basal ganglia, diencephalon, brainstem, cerebellum, etc.
Edited at 2024-03-08 10:13:16
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Clinical Medicine Undergraduate Neurology Section 1 Central Nervous System
- bacteria
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Section 1 Central Nervous System
1. Cerebral hemisphere
concept
1) The surface is covered by the cerebral cortex, and the interior is white matter, basal ganglia and lateral ventricles; the two cerebral hemispheres are connected by the corpus callosum
2) Each cerebral hemisphere is divided into frontal lobe, parietal lobe, temporal lobe and occipital lobe by the connection between the central sulcus, Sylvian fissure and its extension, parieto-occipital sulcus and anterior occipital notch.
3) Insula
4) Limbic system: composed of limbic lobe, amygdala, anterior thalamic nucleus, hypothalamus, etc.
5) The functions of the two cerebral hemispheres are not completely symmetrical and are divided into dominant hemisphere and non-dominant hemisphere.
The dominant hemisphere is mostly on the left
(1) Frontal lobe
[Anatomical structure and physiological functions]
1) Located above the Sylvian fissure and in front of the central sulcus
a The lateral surface is separated from the parietal lobe by the central sulcus
b The base is separated from the temporal lobe by the Sylvian fissure.
c The medial surface is separated from the cingulum by the cingulum groove.
2) Main functional area
a Cortical motor area: precentral gyrus
Arranged in an inverted human shape from top to bottom, with the face upright
Crossed on the left and right, the head and facial muscles are controlled by both sides
The size of the projection area is related to the complexity and importance of the movement of the area it controls.
b Premotor area: in front of the cortical motor area
The cortical center of the extrapyramidal system sends fibers to the thalamus, basal ganglia, and red nuclei, and is related to joint movement and posture regulation.
Also emits the frontopontocerebellar tract, which is related to synergistic movements
c Cortical lateral vision center:
The posterior part of the middle frontal gyrus, where both eyes move sideways in the same direction
d Writing center: the posterior part of the middle frontal gyrus of the dominant hemisphere
e Motor speech center (Broca’s area): the triangular area at the junction of the upper part of the Sylvian fissure of the dominant hemisphere and the posterior part of the inferior frontal gyrus
f frontal lobe
Has extensive contact fibers with memory, judgment, abstract thinking, emotion and impulsive behavior
[Lession manifestations and localization diagnosis]
I lateral surface
Commonly seen in cerebral infarction, tumors and trauma
1) Frontal pole lesions
a Mainly mental disorders
b Symptoms include decreased memory and attention, indifferent expression, slow reaction, lack of initiative and introspection, decreased thinking and comprehensive ability, and may be euphoric or irritable.
2) Precentral gyrus lesions
a Irritant lesions may cause twitching of the upper, lower limbs or face on the contralateral side (Jackson's epilepsy) or secondary generalized seizures
b Monoplegia caused by destructive lesions
3) Lesions in the posterior part of the superior frontal gyrus
Produce strong grip and groping reflexes in the contralateral upper limb
4) Lesions in the posterior part of the middle frontal gyrus
a The irritating lesion causes both eyes to gaze to the opposite side of the lesion
b Destructive lesions cause both eyes to gaze sideways to the lesion
c agraphia
5) Lesions in the posterior inferior frontal gyrus on the dominant side
motor aphasia
II medial surface
Anterior cerebral artery occlusion and parasagittal meningiomas are more common
1) Paracentral lobule lesions can cause paralysis below the knee on the contralateral side and difficulty in urination and defecation.
Urinary and fecal centers: paracentral lobule, S2~S4
2) Parasagittal meningiomas can compress the motor areas of both lower limbs and cause paralysis, accompanied by urinary and defecation difficulties.
III Bottom
Contusions, olfactory groove meningiomas and sphenoidal crest meningiomas are more common
1) Frontal lobe and orbital surface lesions manifest as symptoms such as overeating, excessive gastrointestinal motility, polyuria, and high fever.
2) Foster-Kennedy syndrome: Tumors on the base of the frontal lobe may cause anosmia and optic atrophy on the ipsilateral side, and papilledema on the contralateral side.
(2) Parietal lobe
[Anatomical structure and physiological functions]
1) Located behind the central sulcus, in front of the parieto-occipital sulcus and above the Sylvian fissure
a The front is separated from the frontal lobe by the central sulcus
b The back is separated from the occipital lobe by the line connecting the parieto-occipital sulcus and the anterior occipital notch.
c The lower part is bounded by the Sylvian fissure and the temporal lobe.
2) The interparietal sulcus divides the parietal lobe into the superior parietal lobule and the inferior parietal lobule
3) Main functional partitions
a Cortical sensory area: postcentral gyrus
Receive shallow and deep sensations in the contralateral limb
Falling down
b Application center: the supramarginal gyrus of the dominant hemisphere, related to complex movements and labor skills
c Visual language center: angular gyrus of inferior parietal lobule
[Lession manifestations and localization diagnosis]
I Postcentral gyrus and superior parietal lobule lesions
1) Destructive lesions manifest as complex sensory impairment in the limbs contralateral to the lesion
2) Partial sensory epilepsy in the limb contralateral to the irritant lesion
II Inferior parietal lobule (supramarginal and angular gyrus) lesions
1) Body image disorder
It means that the patient's basic perceptual function is normal, but he loses the ability to distinguish the existence, spatial position and relationship between various parts of his own body.
a hemineglect
b Loss of consciousness
c Finger agnosia
d Inability to recognize self
2) Guzman syndrome
Caused by damage to the dominant angular gyrus
a cannot be calculated
b Finger agnosia
c left-right agnosia
d Agraphia, etc.
3) Apraxia
(3) Temporal lobe
[Anatomical structure and physiological functions]
1) Located below the Sylvian fissure and in front of the parieto-occipital sulcus
a It is separated from the frontal and parietal lobes by the Sylvian fissure, and adjacent to the occipital lobe posteriorly.
b The superior temporal sulcus and inferior temporal sulcus divide the temporal lobe into the superior temporal gyrus, middle temporal gyrus and inferior temporal gyrus.
c Transverse temporal gyrus-auditory center
2) Main functional area
a Sensory speech center (Wernicke’s area): posterior superior temporal gyrus of dominant hemisphere
b Auditory center: middle part of superior temporal gyrus and transverse temporal gyrus
c Olfactory center: uncus and anterior part of hippocampus
d Anterior temporal lobe
e Medial surface of temporal lobe
[Lession manifestations and localization diagnosis]
I Damage to the posterior superior temporal gyrus (Wernicke's area) of the dominant hemisphere
Causes sensory aphasia/Wernicke's aphasia
II dominant hemisphere posterior middle temporal gyrus
naming aphasia
III Uncinate gyrus damage in temporal lobe
"Uncal seizure", phantom smells and tastes
IV hippocampal damage
Epilepsy, delusions, and hallucinations may occur
V Extensive lesions of the dominant temporal lobe or bilateral temporal lobe lesions
Psychiatric symptoms appear, including personality changes, emotional abnormalities, memory impairment, etc.
VI Damage to optic radiation fibers and optic tracts deep in the temporal lobe
Causes changes in visual field, manifested as upward quadrant blindness in the contralateral visual fields of both eyes
(4) Occipital lobe
[Anatomical structure and physiological functions]
1) Located behind the line connecting the parieto-occipital sulcus and the anterior occipital notch
2) The medial surface is divided into cuneiform gyrus and lingual gyrus by calcarine fissure.
3) The occipital lobe is mainly related to vision
4) The visual center/striatal area is located in the occipital cortex above and below the calcarine fissure.
[Lession manifestations and localization diagnosis]
Occipital lobe damage mainly causes visual impairment
I Visual center lesions
1) Irritant lesions causing visual hallucinations
2) Destructive lesions cause visual field defects
a Bilateral visual center lesions produce cortical blindness, manifesting as total blindness
b Lesions of the visual center on one side can produce hemianopia
Features: Homotropic hemianopia in the contralateral visual field, but central vision is not affected, called macular avoidance
c Damage to the lingual gyrus below the calcarine fissure can produce contralateral homonymous upper quadrant blindness
d Damage to the cuneiform gyrus above the calcarine fissure can produce contralateral isotropic lower quadrant blindness
II Lesions around the dominant striatal area
visual agnosia
III Parieto-occipital junction lesions
Distortion
(5) Insula
1) Located deep in the Sylvian fissure and covered by the frontal, parietal, and temporal lobes
2) The function of the insula is related to visceral sensation and movement
3) Insular lobe damage often causes visceral movement and sensory disorders
(6) Marginal leaves
1) It is composed of an arc-shaped structure on the inner side of the hemisphere located around the corpus callosum and the bottom wall of the lower corner of the lateral ventricle.
2) The limbic lobe includes: septal area, cingulate gyrus, hippocampus, parahippocampal gyrus and uncinate gyrus
3) Limbic system: composed of limbic lobe, amygdala, anterior thalamic nucleus, hypothalamus and other structures
2. Internal capsule
[Anatomical structure and physiological functions]
1) The internal capsule is the white matter layer located between the caudate nucleus, lentiform nucleus and thalamus
a The lateral side is the lentiform nucleus
b The medial side is the thalamus
c The anteromedial side is the caudate nucleus
2) Divided into forelimbs, knees and hindlimbs
a The forelimbs radiate through the anterior thalamus
b The genu passes through the corticonuclear tract.
c The hind limbs radiate through the central thalamus, auditory radiation, visual radiation, etc.
[Lession manifestations and localization diagnosis]
I Complete internal capsule damage
1) Commonly seen in cerebral hemorrhage and cerebral infarction, etc.
2) Manifested as triple hemisphere syndrome
a Contralateral hemiplegia
b Contralateral hemianopia
c Contralateral hemi-sensory disorder
II partial internal capsule damage
1-2 or more symptoms of hemiplegia, hemianopia, hemi-sensory disorder, hemi-ataxia, central facial and tongue paralysis on one side, or motor aphasia
3. Basal ganglia/basal ganglia
[Anatomical structure and physiological functions]
1) Composed of caudate nucleus, lentiform nucleus, claustrum, and amygdala
Amygdala (paleostriatum)
striatum
caudate nucleus
lentiform nucleus
Putamen
globus pallidus (old striatum)
2) The basal ganglia is the relay station of the extrapyramidal system
3) The function is to coordinate voluntary movements, muscle tone and postural reflexes, and also participate in the regulation of complex behaviors
[Lession manifestations and localization diagnosis]
I neostriatal lesions
1) Hypotonia-hyperkinesis syndrome occurs
2) Putamen lesions → dance-like movements
3) Caudate nucleus lesions → athetosis
4) Subthalamic nucleus lesions → Hemilateral throwing movements
II Old striatal and substantia nigra lesions
1) Hypertonia-hypotine syndrome occurs
2) Manifested by increased muscle tone, decreased movement and resting tremor
3) More common in Parkinson’s syndrome
4. Diencephalon
structure
1) The diencephalon is the relay station connecting the brainstem and cerebral hemispheres
a The front is bounded by the line connecting the interventricular foramen and the upper edge of the optic chiasm
b The lower part is connected to the midbrain
c There are internal capsules on both sides
2) The diencephalon includes four parts: thalamus, epithalamus, hypothalamus and subthalamus
3) The sagittal narrow space between the left and right diencephalons is the third ventricle
(1) Thalamus
[Anatomical structure and physiological functions]
1) The thalamus is the largest mass of gray matter in the diencephalon
2) It is the subcortical center and relay station for various sensory (except smell) transmission
3) Structure
a pronuclear group
Relay station of the limbic system, communicating with the hypothalamus, mammillary bodies, and cingulate gyrus
related to visceral activity
b Medial nuclear group
The dorsomedial nucleus is connected to other nuclei of the thalamus, frontal cortex, hippocampus, and striatum.
The ventromedial nucleus has connections with the hippocampus and hippocampal gyrus
It is the integration center of somatic and visceral sensations and is also related to the emotional regulation of memory function.
c Lateral nucleus group
ventral anterior nucleus
regulate body movement
ventrolateral nucleus
Relevant to extrapyramidal motor coordination
ventrolateral nucleus
Conducts (deep and superficial) sensations in the body and limbs
ventromedial nucleus
Conduct facial sensation and taste
[Lession manifestations and localization diagnosis]
I Damage to the lateral thalamic nuclei, especially the ventroposterolateral and ventroposteromedial nuclei
Produce contralateral hemiplegia
a All senses are impaired
b Deep sensory and fine tactile impairments are more severe than shallow sensory impairments
c Sensory disturbances in the limbs and trunk are more severe than those in the face
d There may be ataxia caused by profound sensory impairment
e Paresthesia
f Spontaneous pain on the opposite side of the body (thalamic pain)
II Fiber connections from the thalamus to subcortical (extrapyramidal system) nuclei are affected
facial dissociative dyskinesia
III Damage to the connection fibers between the lateral thalamic nuclei and the red nucleus, cerebellum, and globus pallidus
Involuntary movement of the contralateral side of the body
IV Impaired connections between the anterior thalamic nucleus and the thalamus and limbic system
affective disorder
(2) Hypothalamus
[Anatomical structure and physiological functions]
1) Preoptic area
Preoptic nucleus: involved in temperature regulation
2) Supravisual area
Supraoptic nucleus: related to water metabolism
Paraventricular nucleus: related to glucose metabolism
3) Nodule area
Ventromedial nucleus: related to sexual function
Dorsal medial nucleus: related to fat metabolism
infundibular core
4) Mammillary body area
Posterior hypothalamic nucleus: related to thermogenesis and heat preservation
mammillary body nucleus
[Lession manifestations and localization diagnosis]
I Damage to the supraoptic nucleus, paraventricular nucleus and its fiber tracts
1) Central diabetes insipidus can occur
2) Manifested as polydipsia, polydipsia, polyuria, decreased urine specific gravity, etc.
II Damage to the heat dissipation and thermogenesis centers of the hypothalamus
Thermoregulatory disorders
III Damage to the feeding center of the satiety center nucleus of the hypothalamus
Abnormal food intake
IV Damage to the preoptic and posterior reticular formation of the hypothalamus
sleep arousal disorder
V Damage to the ventromedial nucleus and tubercular area of the hypothalamus
Produce reproductive and sexual dysfunction
VI Damage to posterior and anterior hypothalamus
autonomic nervous system dysfunction
(3) Epithalamus
1) Main structures: pineal gland, habenular commissure and posterior commissure
Below the epithalamus is the midbrain, close to the midbrain quadrigemium
2) Lesions are common in pineal gland tumors
3) Tumor compresses the midbrain quadrigeminal causing Parrino syndrome
a Loss of pupillary light reflex (damage to superior colliculus)
b Vertical eye movement disorder (damage to superior colliculus)
c Nervous deafness (damage to the inferior colliculus)
d Cerebellar ataxia (damage to the combined arm)
Symptoms are mostly bilateral
(4) Subthalamus
1) The main structure is the subthalamic nucleus
2) Receive fibers from the globus pallidus and premotor area of the frontal lobe
3) Send fibers to the globus pallidus, substantia nigra, red nucleus and midbrain tegmentum
4) Participate in the functions of the extrapyramidal system
5) Damage to the subthalamic nucleus may cause contralateral hemilateral throwing movements
5. Brainstem
structure
1) Composition: medulla oblongata, pons and midbrain
2) Internal structure: nerve nuclei, ascending and descending conduction tracts and reticular structure
[Anatomical structure and physiological functions]
I brainstem nuclei
1) The midbrain contains the nuclei of the III and IV cranial nerves
2) The pons contains the nuclei of the V, VI, VII, and VIII pairs of cranial nerves
3) The medulla oblongata contains the nuclei of the cranial nerves IX, X, XI, and XII
II brainstem conduction tract
III brainstem reticular formation
1) Some nuclei of the reticular structure receive various information and then transmit it to the thalamus, which is then relayed by non-specific nuclei of the thalamus and then transmitted to a wide area of the cerebral cortex to maintain the person's consciousness, which is called ascending reticular activation. system
2) Damage to the reticular structure may cause disturbance of consciousness
[Lession manifestations and localization diagnosis]
Most brainstem lesions result in cross paralysis, that is, peripheral paralysis of the cranial nerves on the side of the lesion and central paralysis and sensory impairment of the contralateral limbs.
I medulla oblongata
1) Dorsolateral medullary syndrome may occur in lesions in the dorsolateral area of the upper medulla oblongata
vertebrobasilar ischemia
a Dizziness, nausea, vomiting and nystagmus
vestibular nucleus damage
b Paralysis of the soft palate and throat muscles on the side of the lesion, manifested by dysphagia and dysarthria
Damage to nucleus ambiguus, glossopharynx, and vagus nerve
c Ataxia on the lesion side
Damage to the funicular body, spinocerebellar tract, and part of the cerebellar hemisphere
d Horner syndrome
Sympathetic nerve descending fiber damage
e Crossed sensory disorder: facial pain and loss of temperature sensation on the same side, and hemiplegia and hypothermia or loss on the contralateral side
Damage to spinal trigeminal nucleus and spinothalamic tract
2) Damage to the mid-ventral medulla may cause medial bulbar syndrome
a Glossary muscle paralysis and muscle atrophy on the lesion side
hypoglossal nerve damage
b Central paralysis of the contralateral limb
pyramidal tract damage
c Decreased or lost sense of touch, position, and vibration in the upper and lower limbs on the contralateral side
Medial lemniscus damage
II pons
1) Ventrolateral pontine syndrome occurs when the ventrolateral pons is damaged
a Inability to abduct the eyeball on the side of the lesion and peripheral facial nerve paralysis
Abducens nerve palsy, facial nerve nucleus damage
b Contralateral central hemiplegia
pyramidal tract damage
c Contralateral hemi-sensory disorder
Medial lemniscus and spinothalamic tract damage
2) Damage to the ventromedial part of the pons causes ventromedial pons syndrome/Foville syndrome
a Inability to abduct the eyeball on the side of the lesion and peripheral facial nerve paralysis
Abducens nerve palsy, facial nerve nucleus damage
b Gaze toward the opposite side of the lesion
Damage to the lateral visual center and medial longitudinal fasciculus of the pons
c Contralateral central hemiplegia
pyramidal tract damage
3) Lower pontine tegmentum syndrome occurs when the dorsolateral part of the pons is damaged.
a Dizziness, nausea, vomiting, nystagmus
b The eyeball on the affected side cannot abduct
c Paralysis of affected side muscles
d Unable to fixate on the affected side of both eyes
eCrossed sensory disorder
f Decreased or lost sense of touch, position, and vibration on the contralateral side
g Horner syndrome on the affected side
h Hemiataxia on the affected side
4) Locked-in syndrome occurs in bilateral pontine base lesions
a. Conscious, no barrier to language understanding, unable to speak.
b Bilateral central paralysis, which can only be indicated by eye movement up and down
c Bilateral facial paralysis, impaired articulation and swallowing movements
d Total quadriplegia, may have bilateral pathological reflexes
e EEG is normal or has mild slow waves
III midbrain
1) Cerebral peduncle syndrome/Weber syndrome occurs due to damage to the sole of the cerebral peduncle on one side of the midbrain
a All ophthalmoplegia on the affected side except the rectus and superior oblique muscles, and mydriasis
b Contralateral central facial and tongue paralysis and paralysis of upper and lower limbs
2) Red nucleus syndrome occurs when the ventromedial part of the midbrain tegmentum is damaged
a All ophthalmoplegia on the affected side except the rectus and superior oblique muscles, and mydriasis
b Contralateral limb tremor, rigidity or chorea, athetosis and ataxia
c Impairment of deep sensation and fine touch in the contralateral limb
6. Cerebellum
[Anatomical structure and physiological functions]
(1) Structure of cerebellum
1) The cerebellum is located in the posterior fossa of the skull
2) The cerebellum is connected to the medulla oblongata, pons and midbrain through the inferior cerebellar peduncle (rope-shaped body), middle cerebellar peduncle (pontine arm), and upper cerebellar peduncle (combining arm) respectively.
3) The center of the cerebellum is the cerebellar vermis, and the two sides are the cerebellar hemispheres.
4) Three main leaves: flocculent leaf, front leaf and back leaf
5) Three layers of cortex: molecular layer, Purkinje cell layer and granular layer
6) Four cerebellar nuclei (from inside to outside): fastigial nucleus, globular nucleus, embolic nucleus and dentate nucleus
(2) Fibers and connections of the cerebellum
I afferent fibers
1) Spinocerebellar tract
2) Vestibulocerebellar tract
3) pontocerebellar tract
4) Olivocerebellar tract
II efferent fibers
1) Dentate-red nucleus spinal tract
2) Dentate-red nucleus-thalamic tract
3) Fastigial nucleus spinal tract
(3) Function of cerebellum
1) Maintain body balance
2) Control posture and gait
3) Adjust muscle tone and coordinate the accuracy of voluntary movements
[Lession manifestations and localization diagnosis]
The main symptom of cerebellar lesions is ataxia
I Cerebellar vermis damage
Trunk ataxia/axial balance disorder
1) It is difficult to detect a positive sign with eyes closed
2) Drunk gait
3) Opening eyes cannot improve
II Cerebellar hemisphere damage
Ipsilateral limb ataxia
1) The upper limbs are heavier than the lower limbs
2) The far end is heavier than the near end
3) Fine movements are heavier than gross movements
4) Finger-nose test, heel-knee-shin test, and rotation test are clumsy
Horizontal/rotational nystagmus, the tremor becomes thicker when the eyeball looks toward the side of the lesion
cerebellar language
Characteristic lesions
Poetry-like language, explosion-like language
7. Spinal cord
[Anatomical structure and physiological functions]
1) The total length of the spinal cord is 42-45cm, the upper end is connected with the medulla oblongata at the foramen magnum, and the lower end reaches the lower edge of the first lumbar vertebra
2) Divided into 31 segments: 8 cervical segments, 12 thoracic segments, 5 lumbar segments, 5 sacral segments, and 1 caudal segment
a The cervical spinal cord segment is 1 vertebra higher than the cervical vertebrae.
b The upper and middle thoracic cord (T1~T8) is 2 vertebrae higher than the corresponding thoracic vertebrae.
c The lower thoracic cord (T9~T12) is 3 vertebrae higher
d The lumbar spinal cord is located at T10~T12
e The sacral cord is located at T12~L1
f Conus medullaris: The lumbar enlargement gradually tapers downward to form
g Cauda equina: composed of 10 pairs of nerve roots from L2 to telson
3) Two enlargements, six grooves and fissures, and the meningeal membrane is divided into three layers
enlarge
a Neck enlargement: Nerve roots originating from C5 to T2 that innervate the upper limbs
b Lumbar enlargement: Nerve roots originating from L1 to S2 that innervate the lower limbs
6 cracks
a anterior median cleft
b Posterior median cleft
c Anterolateral groove×2
d Posterolateral groove×2
Three-layer film
a dura mater
b Arachnoid membrane
c Pia mater
4) Gray matter of spinal cord
a The front horn is mainly involved in controlling movement of the trunk and limbs
b The posterior horn is involved in the relay of sensory information
c C8~L2 lateral horn is the sympathetic nerve center of the spinal cord, which controls the activities of blood vessels, internal organs and glands.
d The lateral horns of S2 to S4 are the parasympathetic nerve centers of the spinal cord, which innervate the bladder, rectum and gonads.
Urinary and fecal center
5) White matter of spinal cord
a White matter is mainly composed of ascending (sensory), descending (motor) conduction tracts and a large number of glial cells
b Ascending fiber bundle
thin beam and wedge beam
Walking behind the rope
Transmits deep sensations from muscles, tendons, and joints and fine tactile sensations from the skin to the gracilis and cuneate nuclei of the medulla oblongata, and then to the cerebral cortex.
spinocerebellar tract
spinothalamic tract
Conveys pain and temperature sensation to the contralateral limb
c Descending fiber bundle
corticospinal tract
rubrospinal tract
vestibulospinal tract
reticulospinal tract
tectospinal tract
medial longitudinal fasciculus
It is the structural basis of nystagmus and head-eye reflex
6) Spinal reflex
a stretch reflex
When skeletal muscles are pulled, it causes muscle contraction and increased muscle tone
b Buckling reflex
When a limb is exposed to noxious stimulation, the flexor muscles contract rapidly to escape the stimulation.
7) Function of spinal cord
a Upstream and downstream conduction path relay stations
b reflex center
somatic reflex
stretch reflex, flexion reflex, shallow reflex
visceral reflex
Piloerection reflex, bladder micturition reflex, rectal defecation reflex, etc.
[Lession manifestations and localization diagnosis]
(1) Incomplete spinal cord damage
I anterior horn damage
Segmental ipsilateral lower motor neuron paralysis
Shown as: The muscles controlled by the anterior horn of the lesion atrophy and tendon reflexes disappear. No sensory impairment or pathological reflexes, It is often accompanied by fasciculations and a huge integrated potential appears on the electromyogram.
Common in progressive spinal muscular atrophy, anterior horn poliomyelitis, etc.
II posterior corner damage
Ipsilateral dissociative sensory disorder: loss of pain and temperature sensation, preserved touch
Common in syringomyelia and early intramedullary glioma
III Damage near central tube
Bilateral symmetrical dissociated sensory impairment, reduced or absent pain and temperature sensation, and preserved touch
Common in syringomyelia, central canal hydrops or hemorrhage, etc.
IV lateral angle damage
1) Vasomotor dysfunction, sweating disorder and nutritional disorder
The C8-L2 lateral horn is the spinal sympathetic nerve center
2) Horner's sign: narrowing of the eye fissure, enophthalmos, miosis of the pupil accompanied by little or no sweating on the ipsilateral face
C8-T1 side angle
3) Bladder and rectal dysfunction and sexual dysfunction
S2-S4 lateral angle is the parasympathetic center
V anterior cord damage
Damage to the anterior spinothalamic tract
1) Gross sensory impairment below the level of the contralateral lesion
2) Indescribable diffuse pain on the contralateral side of the irritating lesion, accompanied by hyperesthesia
VI posterior cord damage
Vibration and position sense disorders, sensory ataxia
Inability to discern words and geometric shapes written on the skin due to impairment of fine touch
Irritant lesions of the posterior cord may cause severe electric shock-like pain in the corresponding dominant area.
VII Lateral cord damage
Ipsilateral upper motor neuron paralysis below the level of the contralateral limb lesion and contralateral dissociative sensory (pain and temperature) disorder
VIII Spinal cord damage
1) Damage to the fasciculus fasciculata and cuneate fasciculus: deep sensory impairment
2) Pyramidal tract damage: central paralysis
3) Spinocerebellar tract damage: cerebellar ataxia
IX Hemiplegia of spinal cord
1) Spinal cord hemisection syndrome: ipsilateral upper motor neuron paralysis, deep sensory impairment, fine touch impairment, vasomotor dysfunction, and contralateral pain and temperature impairment below the lesion segment
2) The level of contralateral tract sensory impairment is lower than the level of the spinal cord damaged segment
(2) Transverse spinal cord damage
The main symptoms are various sensory loss below the damaged level, upper motor neuron paralysis and sphincter disorder, etc.
1) Symptoms of spinal shock in the acute phase: flaccid paralysis below the level of damage (lower motor neurons), hypotonia, weakened tendon reflexes, negative pathological reflexes and urinary retention
2) After 2 to 4 weeks, reflex activity gradually recovers and turns into central paralysis: increased muscle tone, hyperreflexia, positive pathological signs, reflex urination, etc.
I high cervical cord (C1～4)
1) Upper motor neuron paralysis of the limbs
2) Loss of various senses below the level of damage
3) Sphincter disorder, excessive sweating in the limbs and trunk
4) Often accompanied by occipital pain and limited head movement
II Neck enlargement (C5~T2)
1) Lower motor neuron paralysis of both upper limbs; upper motor neuron paralysis of both lower limbs
2) Various sensory loss below the lesion level
3) Sphincter disorders: urinary and defecation disorders
III Thoracic Cord (T3～12)
The T4-T5 spinal cord segments have poor blood supply and are most susceptible to disease.
1) The upper limbs are normal, but both lower limbs show upper motor neuron paralysis.
2) Various sensory loss below the lesion level
3) Sphincter disorder
4) The damaged segment is often accompanied by a banding sensation
5) Loss of abdominal wall reflex helps locate T7-T12
IV lumbar enlargement (L1～S2)
The nerves that innervate the lower limbs come from lumbar enlargement
1) Lower motor neuron paralysis of both lower limbs
2) Loss of various sensations in both lower limbs and perineum
3) Sphincter disorders: urinary and defecation disorders
Root pain
4) The upper part of the lumbar enlargement is damaged, and the nerve root pain is located in the groin area or lower back
5) The lower part of the lumbar enlargement is damaged, showing sciatica.
V Conus medullaris (S3~S5 and telson)
1) No paralysis of lower limbs and pyramidal tract signs
2) Loss of sensation around the anus and perineum, saddle-shaped distribution, loss of anal reflex and sexual dysfunction
3) Intramedullary lesions may cause dissociative sensory impairment
4) The conus medullaris is the parasympathetic center of sphincter function, and true urinary incontinence may occur.
VI cauda equina nerve root
1) The clinical manifestations of cauda equina and conus medullaris are similar.
2) Symptoms and signs of cauda equina damage may be unilateral or asymmetrical
3) Severe radicular pain and sensory disturbance in the perineum, thighs and calves
4) There may be lower motor neuron paralysis in the lower limbs
5) Sphincter disorders are often not obvious