Frozen Shoulder (Adhesive Capsulitis)

The shoulder joint is surrounded by a capsule of connective tissue that normally allows a very wide range of movement. In frozen shoulder, also known as adhesive capsulitis, this capsule becomes thickened and tight, progressively restricting movement in all directions.

The condition typically progresses through recognised stages: an initial painful, freezing stage where movement becomes increasingly restricted; a frozen stage where pain often eases somewhat but stiffness remains significant; and a thawing stage where movement gradually returns. The whole process commonly takes between one and three years, though this varies between individuals.

In many cases, no clear trigger is identified, and the condition is described as idiopathic. It is more common in people with diabetes and thyroid disorders, and can also follow a period of shoulder immobilisation, such as after an injury, a stroke, or surgery elsewhere in the body that has kept the arm still for an extended period.

It is more common in women and typically affects people between the ages of forty and sixty. Having had a frozen shoulder in one shoulder slightly increases the chance of it later developing in the other.

The typical features of frozen shoulder are:

• Gradual onset of shoulder pain and stiffness, without a specific injury
• Progressive loss of movement in all directions, both when moving the arm yourself and when someone else moves it for you
• Pain that is often worse at night and can disturb sleep
• Difficulty with everyday tasks such as reaching overhead, behind the back, or across the body

The gradual, all-direction pattern of stiffness helps distinguish frozen shoulder from other shoulder conditions, which more often restrict movement in specific directions only.

Diagnosis is usually made clinically based on the pattern of stiffness, though X-rays are often taken to exclude other causes such as arthritis.

Treatment in the painful, freezing stage focuses on managing pain and maintaining as much movement as possible: physiotherapy with gentle stretching, anti-inflammatory or other pain relief medication, and a corticosteroid injection into the shoulder joint, which can be particularly helpful during this early, painful phase.

As the condition moves toward the frozen and thawing stages, physiotherapy continues to help restore range of motion. For the minority of people whose stiffness remains significant and troublesome despite this structured approach, options include hydrodilatation, where fluid is used to stretch the tight capsule, or, less commonly, manipulation under anaesthesia or arthroscopic release of the tight capsule.

Frozen shoulder is generally a self-limiting condition, meaning it tends to resolve on its own over time, though the full course can take one to three years. Most people regain good, functional shoulder movement by the end of this process.

A small proportion of people are left with some residual stiffness even after the condition has run its course, and people with diabetes may experience a more prolonged or resistant course.

Frozen shoulder is a genuinely stiff, often painful condition that follows a recognised course over time, and while it can be frustrating to live with, most people eventually regain good shoulder movement. Physiotherapy and, where needed, injections help manage the painful early stage, and further treatment is available for the minority whose stiffness persists. Gradual, progressive shoulder stiffness and pain is worth having assessed to confirm the diagnosis and rule out other causes.