When i bend my neck i get a warm sensation down my left leg. it feels like warm water pouring down my leg. what could cause this? could it be ms?

Position is Key: The fact that you can reproduce these symptoms by replicating a movement or position links the diagnosis to a musculoskeletal origin. You likely have changes in your cervical spine (neck area) that with the right movement can be made to impinge on a small area of your spinal chord....Which would explain your repeatable symtomology. Ms would not be positional.

Maybe Lhermitte's: You may be stretching or compressing the posterior column of the spinal cord. If there is spinal stenosis, or spinal cord lesions, such as MS, or B-12 deficiency, this could explain your symptoms. Note you have diabetes, which may causes nerve problems. If you take Metformin, B-12 issues may be complication.