The neurologist or your GP should get the following investigations (if not already done);
1) Thyroid-stimulating hormone
2) 25-Hydroxy vitamin D level: Low levels can cause muscle pain and tenderness
3) Vitamin B-12 level: Very low levels can cause pain.
4) Iron studies including iron, total iron-binding capacity, percent saturation, and serum ferritin
5) Magnesium: Low levels can lead to muscle spasms, and pain.
6) The erythrocyte sedimentation rate (ESR)
7) Antinuclear antibody (ANA)
8) Rheumatoid factor
9) Sleep studies
10) Antipolymer antibody assay.
11) MRI of the neck; you may have disc disease in the neck spine also.
12) Electromyography and nerve conduction velocity study.
These will give you the diagnosis. The possibilities are;
a) Pinched nerves in the neck and back.
c) Thyroid dysfunction
I wish your symptoms resolve soon.
I would be happy to assist you further if you need any more information.
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