A pinched nerve in the neck can be responsible for the loss of grip strength. This can be diagnosed by MRI of neck and electromyography and nerve conduction velocity study.
A neuropathy may be the other reason for it. Following are the causes of neuropathy;
2) An underactive thyroid gland
3) Excessive use of alcohol
4) Thiamine deficiency
5) Vitamin B 12 deficiency (pernicious anemia)
6) Vitamin B 6 (pyridoxine) taken in excessive amounts
7) Drugs, medications, herbs
8) Autoimmune diseases
9) Heavy metals such as lead and mercury.
Following investigations are done;
1) Electromyography/nerve conduction studies (EMG/NCS)
2) MRI of the spine and brain
3) blood glucose and glycosylated hemoglobin
4) serum B12 level with methylmalonic acid (with or without homocysteine),
5) serum protein electrophoresis
6) Anti-nuclear antibody
7) Lyme testing
8) Rheumatoid factor
9) Sjogren's syndrome testing (Anti-Ro, Anti-La Antibodies).
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