Pain and stiffness in your shoulder can make every activity, including sleep, difficult. Worsening shoulder pain, especially at night, could mean you have a frozen shoulder, said Dr. Christopher Camp, a Mayo Clinic orthopedic surgeon.

“The scientific name that we give it is adhesive capsulitis, and, basically, it’s a condition when the shoulder gets tight and you can’t move it very well,” Camp said.

He says frozen shoulder happens when the lining that goes around the shoulder joint gets inflamed, possibly the result of a small injury. It thickens over time, forming scar tissue.

“Frozen shoulder exists in three stages, and the symptoms and treatment options depend on which stage you’re in. So the first one is an inflammatory stage,” he said.

That’s the painful stage. Rest and steroid injections may help.

The second stage is when the shoulder is less painful but starts to stiffen. Physical therapy works well then.

The third phase “is what we call thawing, which means it finally starts to relax, loosen up and gain motion back again,” Camp said.

If it doesn’t resolve in six to 12 months, surgery might be an option.

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