Brief Answer:
Deterioration depends on the level and extent of tethering

Detailed Answer:
Hi,

Welcome to HealthCareMagic.com

I am Dr.Bruno Mascarenhas. I have read your question with care and understand your concerns. Let me try to help you

Diastematomyelia is a congenital condition. it means it will be present at birth. The spinal cord is normally a cylinder like structure but in this condition there is a spur in the middle which divides it into two parts one on right and another on left.

This is usually associated with "Tethering of Spinal Cord"

Let me explain what this is. Normally Vertebral Column (the bone) grows much faster than spinal cord (the nerve)

So, as an individual grows, there is relative shortening of the spinal cord in reference to the vertebral column

Hence the spinal cord is situated along the upper aspect of vertebral column and it is not stretched

In diastetomyelia, because of the presence of bony spur, the spinal cord is tethered and gets stretched

This stretching interferes with the blood supply. Hence the patient gets weakness, stiffness, sensation loss, bowel and bladder problems.

Diastetomyelia alone does not need any treatment
But if it is associated with tethering, we need to surgically detach the attachments so that the cord is not stretched.

Hope you found the answer helpful.

If you need any clarification / have doubts / have additional questions / have follow up questions, then please do not hesitate in asking again. I will be happy to answer your questions.

Let me know if I can assist you further.

Take care.

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