1, classic (Xiake type) ALS(C-ALS): upper limbs or lower limbs have characteristic symptoms or signs, and the pyramidal tract sign is clear but not prominent.
2. ALS in the medulla oblongata (B-ALS): These patients are located in the medulla oblongata and have dysarthria and/or dysphagia, atrophy of tongue and muscle tremor. There were no symptoms of peripheral spinal cord injury in the first 6 months after onset. The pyramidal tract sign may not be obvious in the first 6 months, but it should be obvious after that.
3. Flail arm syndrome (FA-ALS): This kind of patients is characterized by progressive development, mainly manifested as weakness and atrophy of the proximal upper limbs. This type includes pathological deep tendon reflex or Hoffman sign in the upper limbs of patients at a certain stage in the course of the disease, but there is no increase in muscle tension or clonus. At least 12 months after symptoms appear, the affected functions are limited to upper limbs.
4. Flail leg syndrome (FL-ALS): The patient is characterized by progressive weakness and atrophy of the distal extremity. This type includes pathological deep tendon reflex or babinski's sign of lower limbs at a certain stage in the course of the disease, but there is no increase in muscle tension or clonus. When there is no distal involvement, the atrophy and weakness of patients with proximal lower extremity diseases are classified as classic ALS.
5. pyramidal tract sign ALS(P-ALS): The clinical manifestations of these patients are mainly pyramidal tract sign, mainly manifested as severe spastic paraplegia/quadriplegia, accompanied by one or more signs: babinski or Hoffmann sign, tendon hyperreflexia, mandibular clonic twitch, dysarthria and pseudobulbar palsy. Spastic paralysis can exist in the early stage of the disease or in the late stage. This kind of patients can show obvious signs of motor neuron damage such as muscle weakness and atrophy in at least two different areas at the time of onset, and EMG has chronic and active denervation damage.
6. Respiratory ALS(R-ALS): These patients show diffuse respiratory dysfunction at onset, have difficulty sitting or breathing when resting or tired, and only have mild signs of spinal cord or medulla oblongata six months after onset. These patients can show the participation of upper motor neurons.
7. Pure motor neuron syndrome (PLMND): These patients have clinical and electrophysiological evidence of progressive LMN involvement. This type does not include:
(1) To study the standardized ganglion segment conduction in patients with motor conduction block;
(2) those with clinical symptoms of UMN;
(3) People with a history of motor neuron-like diseases;
(4) Spinal muscular atrophy with family history;
(5) deletion of SMN1gene;
(6) Hereditary spinal muscular atrophy with abnormal extension of androgen receptor gene;
(7) Neuroimaging study ruled out structural injury.
8. Pure upper motor neuron syndrome (PUMN): The clinical symptoms of upper motor neuron injury in these patients include severe spastic paraplegia/quadriplegia, babinski sign or Hoffmann sign, hyperreflexia, mandibular clonic convulsion, dysarthria and pseudobulbar palsy. This type does not include:
(1) Patients with clinical or electromyographic signs of lower motor neuron involvement according to the Escorial standard during the follow-up period;
(2) Patients with motor neuron-like syndrome;
(3) Patients with family history of spastic paraplegia/quadriplegia;
(4) Patients with hereditary spastic paraplegia related to gene mutation.