Knowing the article: the clinical classification of motor neuron disease

Motor neuron disease (MND) is a chronic progressive neuron disease that mainly affects the cerebral cortex, brainstem, pyramidal tract and motor neurons of the anterior horn of the spinal cord.

Except for amyotrophic lateral sclerosis (ALS), progressive muscular atrophy (PMA), progressive bulbar palsy (PBP) and primary lateral sclerosis (PLS) ) In addition to the 4 main clinical types, there are also relatively rare special types such as flail arm/leg syndrome.

Author: darkpigx Source: "I can eat a little fish and insects," No public MND has been due to the relatively rare cases, the clinical manifestations of the complex and the lack of biological markers, etc.
, to identify relatively difficult.

This article briefly summarizes the clinical classification of MND (typical and atypical) according to the location and clinical manifestations of the disease as follows: 1.
Clinical classification of MND: Classification according to the location and clinical manifestations of the disease (Figure 1) A.
Limb-onset type ALS (Spinal-onset ALS): The upper and lower motor neurons first appear in the upper or lower limbs.
This type accounts for 70% of the total number of patients.

Usually, asymmetric distal upper extremity muscle weakness is the first to appear, which can start from one hand muscle, and can spread to the opposite side after a few months, and gradually appear small hand muscle atrophy.

As the disease progresses, dysphagia and respiratory failure are the most fatal clinical manifestations.

B.
Progressive muscular atrophy (PMA): The clinical feature is progressive degeneration of LMN, including muscle weakness, atrophy, fasciculation, weakening or disappearance of tendon reflexes, etc.
, without UMN involvement.Generally, there is no sensory and sphincter dysfunction.

This type progresses slowly, and the course of the disease can be more than 10 years or longer.

C.
Bulbar-onset ALS (bulbar-onset ALS/Progressive Bulbar Palsy, PBP): PBP is a rapid-onset MND, which is considered to be a bulbar variant of ALS, with slurred speech and dysphagia as the primary manifestations.
Symptoms of limb involvement appear, this type accounts for 25% of the total number of patients.

D.
Facial onset sensory motor neuronopathy (FOSMN): It was first reported and named by Vucic et al.
in 2006.
It is a rare and sporadic special variant of MND.

The disease begins with sensory disturbances in the area innervated by the trigeminal nerve, followed by damage to lower motor neurons, muscle atrophy, and fasciculation.

E.
Flail arm syndrome (FAS): It is a benign clinical variant of ALS, which accounts for 5% to 10% of motor neuron disease.
It is mainly manifested by slowly progressing proximal muscle weakness of the upper limbs and Atrophy is more common with bilateral asymmetric onset.
The symptoms are limited to the upper limbs for a long time, and the bulb and lower limbs are not affected or slightly affected in the early stage.

F.
Hirayama disease (HD): also known as distal upper extremity muscular dystrophy in youth, a rare benign self-limiting lower motor neuron disease that mainly affects the hands and forearms, with progressively worsening muscle weakness and muscles Atrophy, and "cold paralysis" phenomenon.

G.
O'Sullivan-McLeod syndrome (O'Sullivan-McLeod syndrome): Also known as "chronic distal spinal muscular atrophy", the clinical feature is mainly slowly progressive hand muscle weakness and atrophy, which can be Extending to the forearm, there is no sensory disturbance or pyramidal tract signs. H.
Flail leg syndrome (FLS): It accounts for about 2~12.
9% of ALS.
The typical manifestation is asymmetric weakness and atrophy of the lower extremities.
The distal end is heavy and the proximal end is lowered.
Physical examination can reveal the ankles The reflex disappears, the disease progresses slowly, and upper motor neuron involvement may appear in the later stage.

I.
Pseudopolyneuritic ALS (Pseudopolyneuritic ALS): FLS with relatively symmetrical distal muscle weakness and muscle atrophy is also called pseudopolyneuritis ALS, Patrikios variant or peroneal muscle ALS, which is easily misdiagnosed as Peripheral nerve disease.

J.
Primary lateral sclerosis (PLS): PLS is a disease characterized by UMN degeneration, accompanied by relative retention of LMN.
This type is relatively rare, accounting for 1% to 4% of MND.

Manifested as the onset of illness after the age of 40, the most common clinical symptoms of pure PLS are muscle cramps, dysarthria, or strong crying and strong laughter.

Clinical physical examination can find signs of UMN damage, including increased muscle tone, spastic paralysis of limbs, tendon hyperreflexia, positive pathological signs, etc.
, and lack of signs of LMN damage.

Isolated UMN symptoms for at least 3 years without significant weight loss and atrophy are more indicative of PLS.

K.
Mills syndrome (Mills syndrome): It is a rare type of motor neuron disease characterized by hemi-upper motor neuron damage.
There is no lower motor neuron and sensory fiber damage in clinical and electrophysiological examinations.

Current research tends to be a special variant of PLS.

L.
Finger extensor weakness with downbeat nystagmus–motor neuron disease (FEWDON-MND): It is a recently reported variant of ALS that starts with the extension of the distal arm Muscle weakness and atrophy progress more slowly than classic ALS, and the characteristic ocular manifestation is jumping nystagmus. 2.
The characteristic muscular atrophy manifestations of classic ALS: (Picture 2) (Picture 3) (Picture 4) (Picture 5) 1.
Symmetric proximal upper extremity muscular atrophy leads to limited arm lifting (such as barrel man syndrome or flail Arm syndrome).

(Picture 2) 2.
The "sags" of the supraspinatus, infraspinatus, and deltoid muscles on the upper and lower scapula are prone to subluxation of the humeral glenoid joint.

(Figure 3) 3.
"Split hand" is a highly specific clinical feature in the early stage of ALS, manifested as atrophy of the thenar muscles including the abductor pollicis brevis and the first interosseous muscle.

(Figure 4) 4.
Glossal muscle atrophy can be seen when involving the medulla oblongata.

(Figure 5) Clinical manifestations of motor neuron disease involving different parts of the motor neuron signs of the medulla oblongata, thoracic, and lower lumbar motor neuron signs (such as hypotonia, muscle atrophy, muscle jumping, weakened reflexes) tongue muscle atrophy and muscle Fauna tremor atrophy of the small muscles of the hand, (especially the thenar muscles, lumbric muscles and interosseous muscles), back and abdominal muscle jump, foot drop, and upper motor neuron signs (such as spasms, clonus, hyperreflexia, pathological reflexes) Slow tongue extension, strong crying and strong laughter, pseudobulbar palsy, mandibular reflex, sucking reflex, and brow reflex hyperactivity Hoffman’s sign, grasping reflex, pectoral hyperreflexia, abdominal wall reflex disappearance, Babinski’s sign, ankle clonus, Cross adduction reflex 3.
Atypical manifestations of motor neuron disease (Figure 6) The first row from left to right, respectively: A.
Mills syndrome patients, left limb weakness.

B and C.
Patients with FOSMN syndrome, left facial muscle atrophy and tongue muscle atrophy.

D.
Patients with FOSMN syndrome, bilateral lateral muscle atrophy (black arrow) and proximal upper limb muscle atrophy (white arrow).

E.
Patients with O'Sullivan-McLeod syndrome, left hand muscle atrophy.

The second row from left to right, respectively: F.
Flail Leg Syndrome patients.

G.
Patients with flail arm syndrome.

H.
Hirayama's disease patient, the distal right upper limb muscle atrophy.

I.
Patients with progressive bulbar palsy, tongue muscle atrophy, muscle fasciculation.

J.
ALS2 gene-related juvenile ALS, UMN damage is mainly accompanied by lower limb dystonia. (Figure 7) The above picture shows a FEWDON-MND patient.
Picture B shows muscle atrophy of the extensor muscles of the hand and forearm.
Picture C shows a mild pterygoid scapula.

In order to help caregivers to further understand the "gradual freezing" and learn effective care skills in response to the physiological changes in the disease process, the "Guide to the gradually freezing" was published in 2001 to provide reference for patients and their families, and to participate in international patient organizations.
Advanced medical countries observe and learn about nursing knowledge.

After several revisions, updates, and renamed the "ALS Handbook for Care of People Who Frozen", the content was revised again in 2016.

Download link of the Taiwan version of "ALS Handbook of Care for People with Gradually Freezing People": References [1] Kiernan Matthew C, Vucic Steve, Cheah Benjamin C et al.
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