Upper back pain—or, discomfort that can occur anywhere ... A strain can develop suddenly or over time and cause pain, swelling, muscle spasms, and difficulty moving the muscles in the affected ...

Whether it’s a dull ache or sharp spasm, pain between the shoulder blades can be caused by a variety of things. It can be due ...

shoulder and upper back muscles causes these muscles to tear (on a microscopic level). Your body tries to prevent this tearing by forcing these muscles to knot up. This results in muscle spasms.