Brief Answer: Get investigated to exclude more serious condition Detailed Answer: Hi XXXXX, Thanks for the query. There are various possibilities for the arm pit pain you have, but looking at the type of pain you have described, without any swelling/redness/ not being related to movements/ no history of diabetes, I would think of following conditions. - Strained/weak muscles - each time you have burping (mostly due to digestive problem following the duodenal ulcer you had) there is movement of arm muscles giving rise to muscle stress. - Bony/joint weakness/ inflammation due to age might result in such pain. Though your history does not suggest any specific condition, & you will be alright with few pain killers/ physiotherapy,---looking at age, I would suggest To exclude few things. -Pinched nerve can present as the stabbing pain. - Inflammation/ infection of tendons surrounding the shoulder joint. - A chest pain may radiate to arm pit after stress. -a detailed physical examination by a physician to be followed by consultation of Orthopedic surgeon/ Gastroenterologist / cardiologist as per need. - Investigations like routine blood work along with Hb%/ -Blood sugar test, lipid profile, - Serum calcium/ bone density test - X-ray shoulder joint/cervical spine/ -ECG - In case there is some problem, the treatment should be according to expert's advice. I hope nothing serious comes out, still routine health check up & prevention does play a role in healthy aging. I feel the answer was both informative & useful to you. Any further information, I would be happy to provide. Thanks.

---