Disc protrusion t8-t9 - flattening of cord with little csf around cord. having marked changes to gait, very unsteady on feet. neuro next. surgery?

THORACIC DISC: This is rarely a symptomatic occurrence. Real for you. Transcutaneous disc removal for decompresion seems a winner. You have waited long enough. Other methods include microsurgery, Chemonucleolysis if the disc is contained but not thermal lysis.

Probably: When a thoracic disc herniation causes enough pressure on the spinal cord, a condition known as myelopathy can result leading to difficulty walking and problems with balance; surgery is recommended to prevent worsening and increase the chances of a full neurological recovery.

Likely need surgery: It sounds like you have spinal cord compression resulting in myelopathy from your T8/9 disc protrusion. This would likely need to be treated with surgical decompression. You should be evaluated by a Neurosurgeon or Orthopedic spine surgeon as soon as possible.