Defining Frozen Shoulder, Epidemiology, Diagnosis and Prognosis

Eric traces the naming history and the current definition: pain, stiffness and loss of motion with roughly normal X-rays. The condition has an inflammatory component and not everyone develops adhesions, so frozen shoulder is preferred over adhesive capsulitis. Randomized trials show that most gains happen early and that many people never pass through all three classic stages. Epidemiology points to a systemic picture. About 11% develop frozen shoulder after surgery, with higher rates in women, and in a Norwegian study of people with type 1 diabetes for 45 years or more, 59% had frozen shoulder, 73% of them on both sides. Risk factors include female sex, a prior episode, diabetes, thyroid disease and autoimmune disease. Early on it looks like other shoulder problems and is often a diagnosis of exclusion; later it is easy to diagnose but hard to treat. Depression, anxiety and comorbidities predict poor outcomes, and access to surgery appears to depend on age, race and insurance status.