Frozen shoulder: a guide

Frozen shoulder is when the shoulder becomes stiff and painful. In this article, consultant orthopaedic surgeon Professor Duncan Tennent explains why frozen shoulder happens, and how it can be treated.

What is frozen shoulder?

The shoulder is a major joint in a ball-and-socket configuration, where the upper arm bone (the humerus) is anchored to the torso via the shoulder blade (scapula) and the collarbone (clavicle), thanks to a network of soft tissues made of cartilage, muscles, tendons, and ligaments which are encased in what is called a capsule.

Frozen shoulder, also called adhesive capsulitis, occurs when the capsule becomes inflamed, thickening and tightening around the joint. This greatly limits mobility and can cause a significant amount of pain and discomfort.

What causes frozen shoulder?

It can be caused by having to keep the shoulder still for large periods of time, such as having to bind the arm after surgery or injury, but the vast majority have no known cause and are often called “idiopathic adhesive capsulitis”. The condition is more common in women over 40 and people with diabetes and hypothyroidism.

What are the symptoms of frozen shoulder?

There are three stages to frozen shoulder, which can progress slowly over a couple of years:

1. The “freezing” stage, where the shoulder is painful to move and mobility becomes reduced. This can take up to nine months.
2. The “frozen” stage, where there may be less pain in the shoulder, but the stiffness increases. This stage can last up to a year.
3. The “thawing” stage, where mobility starts to gradually restore. This stage can last up to two years.

How is frozen shoulder treated?

Frozen shoulder can get better on its own which can take up to three years, but this isn’t ideal or feasible for most patients to wait for, so they may choose to explore more immediate medical intervention to correct the shoulder and restore function.

To treat frozen shoulder, there are various different techniques a patient an explore.

Most treatments will recommend that the patient commit to practicing exercises and stretches to strengthen the shoulder and expand the range of motion. However, if the pain is persistent, then painkillers from over the counter or non-steroid anti-inflammatory drugs (NSAIDS) can be prescribed to help with the inflammation and soreness.  

For patients who did not respond to painkillers and physical therapy, surgery and other invasive procedures can be considered, such as:

• Steroid shots injected right into the capsule, to reduce the inflammatory response. 
• Hydrodilatation, where sterile water and local anaesthetic are injected into the capsule to stretch the tissues. This can be combined with the steroid shots and it is usually done under ultrasound guidance.
• Shoulder manipulation, where the patient is put under a general anaesthetic and a doctor physically manipulates the shoulder joint to loosen the tight capsule without fear of hurting the patient.
• Shoulder arthroscopy and capsular release​, a surgical procedure that utilises small incisions around the joint through which a tiny camera and other tools can be used to remove some of the toughened tissues.