It’s bad enough your shoulder hurts during the day, but pain at night is too much!
Shoulder pain is commonly due to the four small, deep, fine-tuning tendons that stabilize the shoulder: the rotator cuff. A thin, fluid-filled sac, called a bursa, covers the rotator cuff.
Night pain is frequently due to inflammation in the rotator cuff or bursa.
These structures may be painfully compressed against part of the shoulder blade as you lift your arm under your pillow. Gravity pulls the arm downward when you are upright which relieves this compression. When laying flat, the effect of gravity is eliminated.
Reduce inflammation to enjoy a better night’s sleep. Taking an anti-inflammatory medicine in the evening with food and sleeping upright in a recliner allows gravity to reduce tendon compression. Exercises aimed at strengthening the rotator cuff provide long-term improvement. If these measures fail, you need an orthopedic specialist. A steroid injection may eliminate the inflammation and allow sleep. A specialist can also exclude other disorders that may require additional treatment.