###Human: How can I rule out ALS? ###Assistant: Hi. The various symptoms you have described are due to L5-S1 moderate broad left paracentral disc protrusion mildly distorted the anterior aspect of the thecal sac and abutting without displacing the traversing nerve roots. When a disc prolapses and compresses the spinal cord in cervical and thoracic levels, we get myelopathy. When it compresses the root, we get radiculopathy. But, please note that even when a prolapsed disc does not directly compress the spinal cord or nerve root, it can still produce symptoms if it compresses the blood vessels and interferes with blood flow. As a rule, veins are more easily compressed than arteries and the epidural plexus of veins are compressed by the prolapsed disc. This leads to venous stasis and the metabolites are not washed away from the nerve roots. However, this compression is dependant on the posture. When you move a bit, the pressure gets released and the blood flow resumes and the metabolites are washed and the nerve becomes functionally normal. So, even though you may be having symptoms at one time or another, the moment you walk to your doctor's room and climb the examination couch, all metabolites are washed away and your examination does not find any abnormality. However, the good news is that this condition can be treated by very simple postural adjustments as follows. For further information consult a neurologist online -->