What Causes Frozen Shoulder and Who Is at Risk?

FAQ Series — The Pain Relief Clinic Singapore

What causes frozen shoulder?

Frozen shoulder occurs when the connective tissue surrounding the shoulder joint (the joint capsule) becomes inflamed, thickened, and tight. This leads to the formation of scar tissue, limiting shoulder movement and causing pain. The exact reason why this process starts is not always clear.

Why does frozen shoulder happen?

Frozen shoulder may happen spontaneously, or after a period of shoulder immobility such as:

  • After an injury or surgery
  • Following a stroke or prolonged bed rest
  • Due to pain from another shoulder condition (e.g. rotator cuff injury or arthritis) that leads to disuse

In some cases, it is linked to underlying medical conditions.

What is the main cause of frozen shoulder?

The main cause is often related to inflammation of the joint capsule and reduced use of the shoulder. In people with certain metabolic or hormonal conditions, the risk appears to be higher. It is not usually caused by one single event.

What are the risk factors for frozen shoulder?

Common risk factors include:

  • Age 40–60 years old
  • Female gender (more common in women)
  • Diabetes (both Type 1 and Type 2)
  • Thyroid disorders (hypothyroidism or hyperthyroidism)
  • Previous shoulder injury or surgery
  • Prolonged shoulder immobility
  • Autoimmune or inflammatory diseases

What kind of person is most likely to get a frozen shoulder?

People who are middle-aged, particularly women, and those with chronic medical conditions such as diabetes or thyroid disease, are at higher risk. It’s also more likely to occur if your shoulder has been immobilized for a prolonged period.

When to Seek Help

If you notice increasing shoulder stiffness or pain, especially if it is interfering with daily activities, early evaluation is important. At The Pain Relief Clinic, we help patients understand the cause of their shoulder issues and offer non-invasive treatment solutions that do not require surgery or long-term medications.

Ask Dr Tan A Question About Your Problem