What Is Frozen Shoulder? What Causes Frozen Shoulder? What Is Adhesive Capsulitis?

Editor's Choice
Main Category: Bones / Orthopedics
Also Included In: Rehabilitation / Physical Therapy;  Sports Medicine / Fitness;  Pain / Anesthetics
Article Date: 04 Oct 2009 - 11:00 PDT


Frozen shoulder, also known as adhesive capsulitis, is a common condition in which the articular shoulder capsule (a sac of ligaments surrounding the joint) swells and stiffens, restricting its mobility. It typically affects only one shoulder, but one in five cases affect both.

The term "frozen shoulder" is often used incorrectly for arthritis, even though the two conditions are unrelated. Frozen shoulder refers specifically to the shoulder joint, while arthritis may refer to other/multiple joints.

The shoulder has a spheroidal joint (ball - and - socket joint), in which the round part of one bone fits into the concavity of another. The proximal humerus (round head of the upper arm bone) fits into socket of the scapula (shoulder blade). Frozen shoulder is thought to cause the formation of scar tissue in the shoulder, which makes the shoulder joint's capsule (not to be confused with the rotator cuff) thicken and tighten, leaving less room for movement. Therefore, movement may be stiff and even painful.

The modern English words "adhesive capsulitis" are derived from the Latin words adhaerens meaning "sticking to" and capsula meaning "little container" and the Greek word itis meaning "inflammation".

According to MediLexicon's medical dictionary, adhesive capsulitis is: "A condition in which joint motion becomes restricted because of inflammatory thickening of the capsule; a common cause of shoulder stiffness."

Frozen shoulder is a condition that targets people between 40 and 60 years of age - women more often than men.

What causes frozen shoulder?

The cause of frozen shoulder is not fully understood and in some cases is unidentifiable. However, most people with frozen shoulder have suffered from immobility as a result of a recent injury or fracture. It is common in people with diabetes.

What are the risk factors for frozen shoulder?

A risk factor is something that elevates the risk of developing a disease or condition. For example, smoking is a risk factor for cancer - it elevates the risk of developing lung cancer. Common risk factors for frozen shoulder are:

• Age - being over 40 years of age.


• Gender - 70% of people with frozen shoulder are women.


• Recent surgery or arm fracture - immobility of recovery may cause the shoulder capsule to stiffen.


• Diabetes - two to four times more likely to develop frozen shoulder for unknown reasons; symptoms may be more severe.


• Having suffered a stroke.


• Hyperthyroidism (overactive thyroid).


• Hypothyroidism (underactive thyroid).


• Cardiovascular disease (heart disease).


• Parkinson's disease.

What are the signs and symptoms of frozen shoulder?

A symptom is something the patient feels and/or reports, while a sign is something others, including the doctor observe. For example, pain is usually a symptom, while a rash could be a sign.

The most pervasive sign or symptom of frozen shoulder is a persistently painful and stiff shoulder joint. Signs and symptoms of frozen shoulder develop gradually; usually in three stages in which signs and symptoms worsen gradually and resolve within a two - year period.

There are three stages of frozen shoulder:

• Painful stage - the shoulder becomes stiff and then very painful with movement. Movement becomes limited. Pain typically worsens at night.


• Frozen/adhesive stage - the shoulder becomes increasingly stiff, severely limiting range of motion. Pain may not diminish, but it does not usually worsen.


• Thawing stage - movement in the shoulder begins to improve. Pain may fade, but occasionally recur.

How is frozen shoulder diagnosed?

Doctors will most likely diagnose frozen shoulder based on signs and symptoms and a physical exam; paying close attention to the arms and shoulders. The severity of frozen shoulder is determined by a basic test in which a doctor presses and moves certain parts of the arm and shoulder.

Structural problems can only be identified with the help of imaging tests, such as an X - ray or MRI. An X-ray is a type of electromagnetic radiation that can penetrate most solid objects to create images of an object's interior. An MRI (magnetic resonance imaging) uses magnetic signals to create image "slices" of the soft tissues inside the human body.

What are the treatment options for frozen shoulder?

The aim of treatment for frozen shoulder is to alleviate pain and preserve mobility and flexibility in the shoulder. However, recovery may be slow, as symptoms tend to persist for several years.

Treatment options for frozen shoulder include:

• Painkillers - relieve symptoms of pain. Nonsteroidal anti - inflammatory drugs (NSAIDs), such as ibuprofen, are over - the - counter (OTC, no prescription required) painkillers and may reduce inflammation of the shoulder in addition to alleviating mild pain. Acetaminophen (paracetamol, Tylenol) is recommended for extended use. Prescription painkillers, such as codeine (an opiate - based painkiller) may also reduce pain. Not all painkillers are suitable for every patient; be sure to review options with your doctor.


• Exercise - frequent, gentle exercise can prevent and even reverse stiffness in the shoulder.


• Hot or cold compression packs - help to reduce pain and swelling. It is often helpful to alternate between the two.


• Corticosteroid injections - a type of steroid hormone that reduces pain and swelling. Corticosteroids may be injected into the shoulder joint to alleviate pain, especially in the 'painful stage' of symptoms. However, repeated corticosteroid injections are discouraged as they could cause damage to the shoulder.


• Transcutaneous electrical nerve stimulation (TENS) - numbs the nerve endings in the spinal cord that control pain and sends small pulses of electricity from the TENS machine to electrodes (small electric pads) that are applied to the skin on the affected shoulder.


• Physical therapy (UK: physiotherapy) - can teach you exercises to maintain as much mobility and flexibility as possible without straining the shoulder or causing too much pain.
• Shoulder manipulation - the shoulder joint is gently moved while you are under a general anesthetic (a drug that makes you completely unconscious).


• Shoulder arthroscopy - a minimally invasive type of surgery used in a small percentage of cases. A small endoscope (tube) is inserted through a small incision into the shoulder joint to remove any scar tissue or adhesions.

Your doctor will suggest a suitable option depending on the severity of your signs and symptoms.

If you experience stiffness in the shoulder joint it is recommended that you seek medical attention sooner rather than later in order to prevent permanent stiffness.

How can frozen shoulder be prevented?

Frozen shoulder can only be prevented if it is caused by an injury that makes shoulder movement difficult, in which case the patient should talk to a doctor about what exercises can maintain mobility and flexibility of the shoulder joint.

Written by Caroline Gillott
Copyright: Medical News Today
Not to be reproduced without permission of Medical News Today

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