Frozen Shoulder | Adhesive Capsulitis: Information on Treatment, Symptoms, and Possible Causes

Frozen shoulder is an inflammatory condition of the shoulder joint characterized by painful restriction of both active and passive range of motion. Medically, it is known as adhesive capsulitis.

The central feature is inflammation of the joint capsule, which over time leads to thickening, fibrosis, and adhesions. As a result, the joint progressively loses its normal range of motion and becomes increasingly stiff and painful.

A distinction is made between a primary form—which occurs without any apparent prior injury—and a secondary form that develops following other shoulder conditions.

The shoulder consists of various structures that ensure its mobility, including

• the shoulder joint,
• ligaments and tendons, as well as
• muscles.

These structures work closely together. If any of these structures are impaired, it can affect the shoulder’s range of motion.

A frozen shoulder can be caused by, among other things,

• accidents,
• injuries, 
• surgery,
• shoulder osteoarthritis (cartilage wear in the joint), or
• shoulder impingement

. In these cases, the condition is referred to as secondary frozen shoulder. When experiencing shoulder pain, those affected usually adopt a protective posture and no longer move the shoulder sufficiently. This immobilization promotes the development of frozen shoulder.

The exact cause has not yet been fully elucidated. Hormonal influences, autoimmune processes, and metabolic disorders are among the factors under discussion. In particular, diabetes mellitus, thyroid disorders, and menopause are considered relevant risk factors.

The condition typically occurs between the ages of 40 and 60. Statistically, women are affected slightly more often than men. In some cases, calcium deposits form in the shoulder tendons; this is also referred to as calcific tendinitis.

Shoulder pain accompanied by increasing loss of mobility is referred to as a frozen shoulder © yodiyim / Fotolia

The typical symptoms of frozen shoulder usually develop gradually and worsen over weeks to months.

Characteristic symptoms include:

• mild to severe pain in the shoulder 
• increasing restriction of movement / limited range of motion in the shoulder
• nighttime pain at rest
• loss of strength and compensatory posture
• local swelling and warmth in cases of active inflammation

These symptoms of frozen shoulder usually affect only one shoulder, but can also occur on both sides. The primary symptoms are pain and restricted movement, which significantly hinder daily activities.

The progression usually follows a typical pattern and is divided into stages or three phases:

• Stage I (“Freezing Phase”): Increasingly severe pain—sometimes with sudden onset—and initial limitations in movement begin to occur.
• Stage II (Plateau Phase): Limited range of motion is the dominant symptom. Frozen shoulder is now fully developed, and the pain begins to subside.
• Stage III (“Thawing Phase”): The limitations in movement improve. The pain has almost disappeared.

This course of the disease can last from several months to over two years and is perceived as very distressing by many affected individuals.

To diagnose frozen shoulder, the doctor first conducts a detailed medical history interview. During this process, the doctor asks about symptoms, existing medical conditions, and any past injuries or accidents.

A physical examination can help identify pain and assess the extent of restricted movement.

If necessary, imaging tests such as

• ultrasound (sonography),
• CT (computed tomography),
• MRI (magnetic resonance imaging).

These allow the doctor to identify or rule out damage to the structures involved in the joint. These tests also serve as preparation for surgery.

The treatment of frozen shoulder depends on the stage, pain intensity, and cause of the condition.

In the early stages, conservative treatment or therapy is usually the first line of treatment. This includes anti-inflammatory medications, cortisone injections, targeted physical therapy, and therapeutic exercises. In addition, manual therapy may be used for gentle mobilization to gradually improve range of motion and relieve pain.

The goal of therapy is to control inflammation, reduce pain, and restore joint mobility. These measures are carried out under close medical supervision, often by an orthopedic surgeon or specialist in orthopedics.

If treatment is unsuccessful or if there are significant structural changes, surgical treatment may be necessary. In this procedure, the thickened joint capsule is released using arthroscopy. This is a minimally invasive surgery and is now considered a well-established procedure in shoulder surgery. The procedure is performed surgically and requires intensive follow-up physical therapy afterward.

The surgical procedure can usually be performed using a minimally invasive technique (shoulder arthroscopy). The video demonstrates the procedure for shoulder arthroscopy:

If frozen shoulder is treated, the prognosis is generally favorable. In most cases, normal function of the shoulder joint can be largely restored.

Without adequate treatment, however, the course of the condition can be protracted and lead to chronic loss of function or osteoarthritis. Relapses are possible but rare. 

Frozen shoulder generally cannot be prevented. However, to avoid the condition from worsening, you should see a doctor as soon as the first symptoms appear.

Frozen shoulder is a complex, painful condition of the shoulder that requires early diagnosis and structured treatment. Thanks to modern conservative and surgical treatment methods, very good results can be achieved today. Early initiation of treatment, an individually tailored approach to managing frozen shoulder, and consistent follow-up care are crucial.

What does the term “frozen shoulder” mean?

It refers to a painful restriction of movement in the shoulder joint caused by inflammatory changes and shrinkage of the joint capsule.

How is the condition diagnosed?

Diagnosis is based on medical history, physical examination, and imaging techniques such as ultrasound, MRI, and CT.

How long does recovery take?

The course of the condition can last 12 to 36 months, depending on the stage, treatment, and individual factors.

Is surgery always necessary?

No. In most cases, conservative treatment is sufficient. Surgery is recommended only for stiffness that does not respond to treatment.

What role does exercise play?

Targeted mobilization is important, but overexertion should be avoided. Physical therapy is always performed under supervision and as part of the treatment plan.