<s>[INST] My husbands elbow started swelling yesterday. It looks like tennis elbow but its soft and feels like its full of water just like a blister. Its about 6 diameter. He hasnt banged his elbow or injured it in anyway. He is getting pain down his arm and his fingers keep twitching. [/INST] Hi there. It looks as though he has developed a fluid collection possibly because of arthritis of the elbow. Pain down the arm and shooting sensation is due to possible compression of the ulnar nerve behind the elbow which could be due to the swelling. I advise you to perform cold sponging in the area. He can take anti-inflammatory like Tablet Ibuprofen 200 mg twice a day after a meal. Kindly get him seen by an Orthopaedician or Hematologist who may need to aspirate the fluid and check for the cause like Rheumatoid arthritis, Gout etc. </s>