Multiple sclerosis is a demyelinating disease of the central nervous system (demyelinating because the disease is characterized by the loss of the myelin sheath around the axons of the nerve cells). As I have stated in my previous posts on MS (see http://braindiseases.info for all the previous posts on MS), the disease is characterized by plaques which are disseminated in space and time.
Most of these plaques (demyelinating lesions of MS) are seen in the brain but a few patients have what is loosely called spinal MS or rather MS in which the plaques are more commonly seen in the spinal cord (remember the spinal cord is a part of the central nervous system). These patients with spinal MS present with slightly different clinical signs and symptoms. They may present with what is called transverse myelitis (this is an involvement of the spinal cord usually at the cervical or thoracic level). Transverse myelitis can be devastating because all the descending motor fibers from the brain and the ascending sensory tracks are packed in the small diameter of the spinal cord. So any involvement of the spinal cord has the potential to affect all these tracks. Depending upon the level of cord involvement patients may have either weakness of just the legs (paraparesis or paraplegia) or all the four limbs may be involved (quadriparesis or quadriplegia). Usually the bladder and bowel are involved too and patients may have complaints of urinary incontinence. Sexual dysfunction is also commonly reported (erectile dysfunction in males, see my previous post on it).
As the involvement of the brain is less, these patients are relatively well preserved cognitively and may not have prominent cerebellar findings.
Spinal involvement in MS is treated in much the same way as other forms of MS. Your doctor may use a course of intravenous corticosteroids if you present to the hospital with acute transverse myelitis. Immuno modulating drugs like interferons may later be prescribed.
Nitin Sethi, MD