Brief Answer:
Nano Second Unsteadiness is because Spinal Cord / Nerves are affected

Detailed Answer:
Hi,

Welcome to HealthCareMagic.com

I am Dr.Bruno Mascarenhas. I have read your question with care and understand that you have severe degenerative disc disease of the whole spine and for the past 15 months, you suddenly lose your balance, causing you to to fall. You do not get dizzy, you do not feel faint, and you do not get headaches. You want to know what is causing the nano-second unsteadiness. Let me explain.

Your Balance (steadiness) is dependant on three factors
1. The Signals from your Muscles and Joint which go to you Brain. These signals travel from muscles and joints first through the peripheral nerves and then through the posterior part of your spinal cord and tell your brain the position of various joints and muscles.
2. The Brain Which processes these signals and orders the muscles to contract to maintain balance.
3. The Signals which come from Brain to Various Muscles. These signals travel first through the anterior and lateral parts of your spinal cord and then through the nerves to the muscles.

If one or more of the above three are affected, Balance will be lost and the person will feel unsteadiness and fall down.

When Brain is affected, in addition to unsteadiness and loss of Balance, there will be dizziness, feel of fainting and headaches.

But, when the Spinal Cord and Peripheral nerves alone are affected, only the input pathway and output pathway are affected. Hence there won't be dizziness, feel of fainting and headaches. The problem will be only with Balance.

In your case, your brain is not affected. Only your spinal cord and peripheral nerves are affected. So you do not get dizziness, feel of fainting and headaches. Your Problem is Unsteadiness and Loss of Balance.

The Pins and Needle Sensation of your Hand instead of Pain can be due to two reasons
1. Peripheral Neuropathy.
2. Carpal Tunnel Syndrome

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.

Best Wishes for Speedy Recovery.
Let me know if I can assist you further.
Take care.

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