Multiple Sclerolosis is called "encephalomyelitis disseminata" and could be considered a myelopathy in the broad sense. Myelopathy is caused by trauma of the spinal cord.

Damage to the nerves (myelopathy) of the spinal cord caused by infection with the human T lymphotrophic virus type-1 is termed HTLV-1 associated myelopathy.

what is the treatment for displacement of lumbar intervertebral disc without myelopathy

An Orthopedist.

No, it shouldn't be capitalized.