Causes of Shoulder Pain.

• Arthritis. There are numerous types of arthritis, but each one describes inflammation of at least one joint, such as the shoulder.
• Osteoarthritis.
• Rheumatoid arthritis.
• Bursitis.
• Adhesive capsulitis.
• Rotator cuff tears.
• Spine or disc issues.

Gas.

 Pain in your left shoulder after you eat may be a trapped gas bubble.

When you digest food, bacteria in digestive tract can form gas and it can get stuck. This can cause a type of “referred pain” to shoulder area.

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