Brief Answer:
variable causes...

Detailed Answer:
Hi,

Upper arm or arm pain may be due to neck, shoulder or local arm causes which can only be ascertained by careful physical examination of the mentioned regions, along with tests for movements, tendons, ligaments and nerve conduction testing. Causes can be variable from cervical spondylosis, to shoulder arthritis or supraspinatus tendinitis (most common causes) or local bone and muscle nerve causes-less commonly. The possibilities can be narrowed down through complete clinical history, careful local and systemic examination. That being said, most of the causes have good remedy. So don't be overly concerned.

As of now TILL you get an orthopedic appointment, I may consider taking over the counter pain and anti-inflammatory medicines like Aleve or Advil,and prilosec OTC, doing hot fomentation and rubbing of muscle relaxant gel//cream locally in pain area.

In such cases,after localizing main area involved, screening through X ray, MRI and other muscle-nerve physiological and conduction tests are advised, apart from these, blood sugar, CRP, ESR, CBC, creatinine and urea for general health status is done before definitive treatment is advocated. Your history of past illness and family history is equally contributory and asked for by examining doctor

regards,

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