Hi,
Thanks for posting your query.

The lump between the elbow and shoulder without any history of an injury is likely to be due to inflammation of the tendons around the area.

You can help the improvement by-
1. Give adequate rest to the arm.
2. Apply cold therapy.
3. Get some anti-inflammatory medication prescribed from your orthopedician.
4. Immobilize the arm for a short period.
5. Soft tissue therapy can be used to break down adhesions that may be restricting the nerve.
6. Neural stretching exercises are helpful under the care of a physiotherapist.

Surgery might be needed in severe cases with persistent symptoms.

I hope this answers your query.
In case you have additional questions or doubts, you can forward them to me, and I shall be glad to help you out.
Please accept my answer in case you do not have further queries.

Wishing you good health...
Regards.
Dr Saurabh Gupta.
Orthopaedic Surgeon.

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