Brief Answer:
Quite likely due to nerve entrapment, get it looked at by a neurologist or orthopedic surgeon.

Detailed Answer:
Hello and welcome to Ask a Doctor service.

I have reviewed your question and understand your concern.

Alterations in sensations are usually the first symptoms of a nerve entrapment and need to be examined to find out the exact location of entrapment and treatment depends on the location and presence of inflammation if any.

The little finger is supplied exclusively by the ulnar nerve.

The ulnar nerve passes through a tunnel under the ligaments that connect the bones in the hand, if there is any swelling underneath these ligaments, the nerve gets compressed, leading to altered sensations (decreased or increased sensations), or paresthesias like numbness or tingling.

Please get yourself examined by an orthopedic surgeon or a neurologist to find out the location of this nerve entrapment.

Treatment usually depends on the degree of nerve compression and associated inflammation.

Mild inflammation can be treated with analgesics and antiinflammatory medication such as NSAIDs or local steroid injections.

Severe compression and inflammation will require surgical release of the nerve to preserve its function.

I hope this answers your concern. Please do write back if you have any additional concerns.

Wishing you speedy recovery.

Best regards.

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