Entrapment of the ulnar nerve in the elbow (ulnar tunnel syndrome) occurs when the ulnar nerve of the arm is compressed or irritated.
In many cases, the exact cause is unknown. Known causes may include direct nerve injury, prolonged pressure on the nerve, pressure on the nerve caused by inflammation or injury of nearby body structures, etc.
Symptoms may include abnormal sensations in the little finger and part of the ring finger, usually on the side of the palm; weakness; loss of coordination of the fingers; claw deformity of the hand and wrist; pain; numbness; decreased sensitivity; tingling or burning sensation in the areas controlled by the nerve.
The diagnosis is reached through medical questioning and physical examination. Additional tests may include blood tests, electromyogram, nerve conduction tests, nerve biopsy.
In some cases, no treatment is required. Medical treatment is based on taking painkillers and antiinflammatories, and physiotherapy. Surgery to relieve nerve pressure may help if symptoms worsen or if there is evidence that part of the nerve is wearing off.
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