Brief Answer:
Spinal cord instability should be considered.

Detailed Answer:
Hello and thanks for using HCM.

I have read your query and understand your concerns.

Worsening of neurological symptoms with certain positions such those prescribed by you, are most likely related to spinal column instability (spondylolysthesis) and/or spinal cord compression.

Another possibility is multiple sclerosis, but less likely in your case.

There is need to get examined clinically about any additional neurological signs such abnormal reflexes and imaging studies such dynamic x-rays (flexion/extension position), MRI of cervical and lumbosacral spine too, in order to achieve a correct diagnosis.

Discuss with your primary care Doctor about these examinations to be done.

Hope you found the answer helpful.

Let me know if I can assist you further.

Greetings.

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