Frozen shoulder, also known as adhesive capsulitis, is a condition characterized by stiffness and pain in the shoulder joint, resulting from inflammation and thickening of the shoulder capsule. This condition typically develops gradually and can significantly limit the range of motion in the shoulder. It often occurs after an injury or period of immobilization, but the exact cause can be unclear. Symptoms may include persistent pain, difficulty in moving the shoulder, and a feeling of tightness in the joint. Treatment typically involves physical therapy to improve flexibility and strengthen the shoulder, along with pain management strategies.