What is Frozen Shoulder?
Frozen shoulder is a condition involving inflammation and thickening of the joint capsule surrounding the shoulder, leading to progressive restriction of movement. It is classically described as progressing through stages: an early painful phase, a stiff “frozen” phase, and a later recovery or “thawing” phase. The underlying cause is not fully understood, but the process results in capsular tightening and reduced joint volume. This explains why both active and passive shoulder movements become restricted, distinguishing frozen shoulder from other causes of shoulder pain.