Brief Answer:
may be peripheral neuropathy, a neurologist would be best

Detailed Answer:
HI, thanks for using healthcare magic

You should consider a neurologist, a doctor that specializes in diseases that affect the nervous system- brain, spinal cord and the nerves supplying organs and muscles.

The abnormal sensations and locking may be due to neuropathy which is abnormal function of the nerves. It can be temporary or permanent and there are different possible causes.

The most common causes are--(1) liver or kidney disease
(2)side effect of medication
(3)trauma to the nerves eg arthritis of the spine
(4)low levels of vitamin b12 and folate
(5)abnormal levels of vitamin b 6
(6)thyroid disease
(7)infection such as shingles though this would normally affect a particular area
(8)nerve conditions such as ms or stroke

If the symptoms are severe or persistent then you may need to be assessed , this includes physical examination, blood tests and imaging such as an x ray of the spine.

There are medications that can help with neuropathy such as tegretol, lyrica, amitriptyline etc

Specific treatment depends on the cause found

I hope this helps, feel free to ask any other questions

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