Motor neuron disease itself does not cause physical pain, but is clinically known as amyotrophic lateral sclerosis, which is a neurodegenerative disease that is characterized by simultaneous damage to upper and lower motor neurons. As the disease progresses, the patient may have difficulty moving the limbs. In severe cases, the patient may have respiratory muscle paralysis, resulting in respiratory distress and respiratory failure, and if necessary, the patient may be ventilated. In mild cases of motor neuron disease, pain can be caused by incorrect posture during rehabilitation exercises, but not by the motor neurons themselves.