What is frozen shoulder?

Frozen shoulder is also known as adhesive capsulitis and is characterized by the gradual development of a very painful and stiff shoulder.  This diagnosis can be made if no other diseases are affecting the shoulder and no evidence of bone loss (osteopenia) is seen on radiographs of the shoulder joint.

This condition usually affects people aged between 40-60 years.  In addition, men are less commonly affected by this condition than women.   Suffering from diabetes mellitus may increase your risk of developing frozen shoulder by 5 times.  Furthermore, the non-dominant shoulder is more commonly affected by frozen shoulder and the other shoulder becomes affected within 5 years.  This condition occurs gradually and resolves on its own after around 2-3 years.

What are the risk factors for frozen shoulder?

The exact cause of frozen shoulder is not known.  However, there are several factors which may increase your risk of developing frozen shoulder and these include:

• Age: People aged between 40-60 years are more at risk of developing frozen shoulder.
• Sex: Females are more at risk of developing frozen shoulder than males.
• Diabetes mellitus: People suffering from diabetes mellitus are 5 times more at risk of developing frozen shoulder.
• Shoulder trauma
• Shoulder surgery

• Rotator cuff tear: This is tearing of your shoulder muscles which causes pain when moving the arm away from the body.
• Prolonged immobilisation: Prolonged immobilisation after cardiac, head or breast surgery may increase your risk of developing frozen shoulder.  A broken arm also may cause prolonged immobility of the shoulders which may lead to frozen shoulder.
• Stroke
• Cardiac diseases
• Cancer
• Thyroid diseases
• Drugs: Drugs such as fluoroquinolones, antiretrovirals and protease inhibitors may increase your risk of developing frozen shoulder.

What are the signs and symptoms of frozen shoulder?

Frozen shoulder characteristically develops slowly and in 3 stages, namely, freezing stage, frozen stage and thawing stage.  The freezing stage is when any movement of the shoulder causes pain.  The frozen stage is when the pain start to decrease but the shoulder becomes stiffer and your shoulder range of motion becomes very limited.  The thawing stage is when your shoulder range of motion start to increase which indicates that the condition is starting to resolve.  The signs and symptoms of frozen shoulder include:

• Gradual increase in shoulder pain
• Gradual decrease in your shoulder range of motion
• Inability to sleep on the affected side due to pain
• No abnormal findings on x-ray of your shoulder

Making a diagnosis

To make a diagnosis, your doctor will first take a detailed history from you to know more about your symptoms.  After the history taking, your doctor will perform a thorough physical examination to look for signs of frozen shoulder.  Frozen shoulder can be diagnosed using only a good history and physical examination.  However, your doctor will order some tests in order to rule out other diseases and to confirm the diagnosis.  These tests mainly include laboratory studies and imaging studies.

Laboratory studies

Laboratory studies are rarely required for the diagnosis of frozen shoulder.  However, if your doctor suspects another disease causing your signs and symptoms, he/she may order these tests:

• Erythrocyte Sedimentation Rate (ESR)
• Complete Blood Count (CBC)
• Blood glucose
• C-Reactive Protein (CRP)
• Haemoglobin A1c (HbA1c)
• Thyroid-Stimulating Hormone (TSH)
• Free Thyroxine (FT4)
• Free Thyroxine Index (FTI)

Imaging studies

Routine imaging studies are not required in the diagnosis of frozen shoulder.  However, they are done to rule out other diseases.  Imaging studies include:

• Radiography: Routine Radiography do not have a role in the diagnosis of frozen shoulder.  However, x-ray of the shoulder should be done in all cases in order to rule out any other diseases.

• Ultrasonography: This test can be used to measure the thickness of the ligaments in the shoulder and to detect inflammatory processes.
• Arthrography: Arthrography is an x-ray of the inside of a joint after a contrast material or dye has been injected into the joint.
• Positron Emission Tomography (PET) or Computed Tomography (CT) scans: These scans can be used to assess the thickness of the ligaments inside your shoulder and rule out any other diseases.
• Magnetic Resonance Imaging (MRI) scan: An MRI scan is not usually indicated in frozen shoulder.  However, if there is no improvement after 6 weeks to 3 months, an MRI scan can be used to rule out a rotator cuff tear or other diseases.
• Arthroscopy: Arthroscopy is insertion of tube containing a camera at its end to have direct visualisation of the inside of the shoulder joint.  Findings suggestive of frozen shoulder include scarring, chronic inflammatory cells and thickening of the tendons and ligaments.

What are the treatments of frozen shoulder?

The main goals of frozen shoulder treatment are to relieve pain and restore your shoulder function.  Frozen should is a condition that usually resolves on its own.  Physiotherapy and home exercises are usually the first-line treatments for all stages of frozen shoulder.  Medical and surgical care can also be used to relieve the signs and symptoms associated with frozen shoulder.

Medical care

The medications used in the management of frozen shoulder include:

• Non-Steroidal Anti-Inflammatory Drugs (NSAIDs): As frozen shoulder may be accompanied by an inflammatory process, NSAIDs may be useful.  When the inflammation decreases, the shoulder pain also decreases.  Examples of NSAIDs include ibuprofen and diclofenac.
• Oral glucocorticoids: These medications may be used instead of NSAIDs and they provide stronger anti-inflammatory effect.  Oral glucocorticoids are used when there is significant shoulder pain or when the condition has been present for more than 2 months.  Diabetes mellitus is an absolute contraindication for the use of oral glucocorticoids and may be increase your blood sugar level. These medications are usually given over a course of 2-6 weeks.
• Corticosteroid injections: This is when the drug is injected directly into the joint.  These injections can be used in conjunction with NSAIDs or oral glucocorticoids.  It provides rapid pain relief for a period of 6 weeks.

Surgical care

The surgical procedures are performed when the condition is not responding to medical care and physiotherapy.  These include:

• Manipulation under anaesthesia: This procedure involves your doctor putting you under general anaesthesia to move your shoulder in different positions, in an attempt to loosen the tightened tissue.
• Hydrodilatation: This procedure involves your doctor injecting large volumes of water into your shoulder joint using ultrasonography as a guide.  This helps to distend the shoulder capsule in order to stretch the tissue, making it easier for you to move the joint.

• Arthroscopic surgery: This surgery involves your doctor inserting a tube containing a camera at its end and other tools into a small incision in order to remove scar tissue from the inside of your shoulder.  This procedure help to relieve pain and improve your shoulder range of motion.

Prognosis

Frozen shoulder usually resolves on its own.  Unfortunately, long-term disability has been reported in 15% of cases, permanent function loss in 7-15% and persistent symptoms in 40%.

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