Related: Anatomy of the Human Shoulder Joint People with RA who have shoulder involvement will have pain in both shoulders.

Ball and socket joints also allow flexion and extension. Flexion of the shoulder joint occurs when the humerus (upper arm) moves forwards from the rest of the body, which happens at the end of an ...

Dislocation—complete loss of contact between joint surfaces that requires a reduction manoeuvre to restore normal anatomy. This may be acute (first ... partial loss of contact between joint surfaces ...