Frozen shoulder is a condition that causes pain and stiffness in the shoulder, making it hard to move the arm. It often develops slowly and can last for months or even years. Most people improve over time with the right treatment, though some may continue to have mild symptoms. Physical therapy and other treatments can help restore movement and reduce pain, leading to better shoulder function.

Frozen shoulder is a condition that leads to pain and a significant loss of motion in the shoulder joint. It is also known as adhesive capsulitis. The condition affects a person’s ability to move the shoulder on their own (active motion) and also limits how far the shoulder can be moved by someone else (passive motion).

Frozen shoulder most often affects people between the ages of 40 and 60, and it is more common in women. It usually involves only one shoulder, but sometimes both shoulders can be affected over time. The condition can interfere with daily activities, such as dressing, reaching overhead, or bathing. While frozen shoulder often gets better on its own, treatment can help speed up recovery and reduce discomfort.

Frozen shoulder develops when the capsule of tissue surrounding the shoulder joint becomes inflamed, thickened, and tight. This leads to the formation of bands of scar-like tissue called adhesions, which restrict movement. The amount of lubricating fluid in the joint may also decrease, making movement harder.

The exact cause of frozen shoulder is not fully understood. In many cases, it appears without a clear reason. Sometimes, it follows an injury, surgery, or a period when the shoulder has been immobilized and not moved for a while. Certain medical conditions, such as diabetes and thyroid disorders, are linked to a higher risk of developing frozen shoulder. Inflammation and changes in the body's immune response may play a role in causing the tissue changes seen in this condition.

Frozen shoulder can be classified as either primary (when it occurs without a known cause) or secondary (when it follows trauma, surgery, or another shoulder problem). Both types involve a process in which inflammation leads to fibrosis (thickening and stiffening) of the shoulder capsule.

Frozen shoulder is more likely to develop in people with certain medical conditions, after injuries or surgeries, or due to lifestyle factors. Risk factors include:

• Having diabetes or thyroid disorders increases the likelihood of frozen shoulder.
• Extended periods without moving the shoulder, such as after surgery or injury, can contribute to the condition.
• Previous shoulder injuries, including rotator cuff problems or fractures, may be a factor.
• Neurological conditions like Parkinson’s disease, or events such as a stroke, are linked to higher risk.
• Surgeries involving the heart or breast, or certain medications (such as those for HIV), have been associated with frozen shoulder.
• Hormonal changes, especially during menopause, may influence risk.
• Being overweight or physically inactive could play a role.
• Other health issues, such as cardiovascular disease, cervical spine problems, or Dupuytren’s disease (a hand disorder), may also be involved.

Even without these risk factors, some people still develop frozen shoulder for reasons that are not always clear.

People with frozen shoulder usually notice increasing pain, growing stiffness, and difficulty moving their shoulder, with symptoms that tend to worsen over time. Specific symptoms may include:

• Dull or aching pain is common, often felt over the outer shoulder and sometimes the upper arm.
• Pain is usually worse in the early stages of the condition and when moving the arm.
• Stiffness makes it hard to move the shoulder.
• Loss of range of motion affects daily activities, such as reaching overhead, behind the back, or across the chest. Difficulty performing tasks such as dressing, bathing, or putting on a coat is common.
• Night pain is frequent, especially in the early stages, and can disrupt sleep.
• The shoulder may feel stuck or locked at the limits of movement.

Symptoms often progress through three stages:

• Freezing stage: Increasing pain and gradual loss of movement, lasting two to nine months.
• Frozen stage: Persistent stiffness develops while pain may lessen, lasting four to 12 months.
• Thawing stage: Slow improvement in movement, lasting five to 24 months.

Doctors diagnose frozen shoulder by asking about symptoms and performing a physical exam to check for pain and limited movement in the shoulder.

During the medical history review, the doctor will ask when symptoms began and about the duration and pattern of pain and stiffness. They will also ask about any injuries, surgeries, or medical conditions that might contribute to the problem.

In the physical exam, the doctor will:

• Move the shoulder in different directions to check for limited movement and pain
• Compare active range of motion (how far the person can move their shoulder on their own) and passive range of motion (how far it can be moved by another person)
• Assess which movements are most restricted, often finding that external rotation (turning the arm outward, away from the body) and reaching behind the back are especially limited
• Check for tenderness around the joint and observe for muscle wasting due to disuse

If the diagnosis is unclear or to rule out other causes, doctors may use additional tests such as:

• X-rays: Used to rule out bone problems such as arthritis or fractures
• Magnetic resonance imaging (MRI): Helps identify soft tissue injuries, such as rotator cuff tears, and assess the shoulder capsule
• Ultrasound: Can show inflammation or other soft tissue changes
• Diagnostic injection: A doctor may inject an anesthetic into the shoulder; if movement does not improve after the injection, frozen shoulder may be the cause

Treatment for frozen shoulder aims to reduce pain and restore shoulder movement. Most people improve with nonsurgical treatments, though recovery can be slow.

• Physical therapy is the main treatment, focusing on stretching and range-of-motion exercises to improve flexibility and strength. Therapy may be supervised or done at home, and sometimes heat is used before stretching.
• Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen, for those able to take them, can help reduce pain and swelling.
• Acetaminophen may be used for pain relief if NSAIDs are not suitable.
• Steroid injections (corticosteroids) may be given directly into the shoulder joint to decrease inflammation and provide short-term pain relief, especially in the early stages.
• Hydrodilatation involves injecting a large volume of sterile fluid into the shoulder joint to stretch the capsule and improve movement. This procedure may be combined with steroids and is performed under imaging guidance (using ultrasound or X-ray to help the clinician see the needle’s position).
• Suprascapular nerve block (an injection that numbs one of the main shoulder nerves) may be used in some cases to reduce pain and improve mobility. This nerve can also be ablated (destroyed using heat, cold, electrical pulses, or other types of energy) for long-term relief.
• Other therapies, such as shockwave therapy (sound-wave pulses applied to the shoulder), electrical stimulation (gentle electrical currents), acupuncture (a traditional Chinese medicine technique in which thin needles are inserted into the skin at specific points on the body) or laser therapy (focused light), may be used in addition to other treatments, but evidence for their effectiveness is limited.

If nonsurgical treatments do not help after several months to a year, surgery may be considered:

• Manipulation under anesthesia: While the person is under anesthesia and unconscious, the doctor moves the shoulder to stretch or tear the tight capsule and adhesions.
• Shoulder arthroscopy: In this minimally invasive procedure, small instruments are inserted through tiny incisions to cut and release (loosen) the thickened capsule and remove scar tissue.

Complications from frozen shoulder can affect shoulder function and overall well-being. These complications may arise from the condition itself or from treatment and can include the following:

• Persistent stiffness and pain may continue even after therapy, affecting daily activities.
• Loss of shoulder movement can lead to muscle wasting and weakness from disuse.
• Secondary injuries, such as labral tears or rotator cuff problems, may develop due to altered shoulder mechanics.
• Surgical procedures, such as manipulation under anesthesia, can sometimes cause fractures or tendon ruptures if the shoulder is moved forcefully.
• Rarely, shoulder dislocation or other joint injuries may occur during treatment.
• In people with diabetes or thyroid disorders, recovery may be slower and stiffness may persist longer.
• Recurrence of frozen shoulder can happen, especially if underlying risk factors are not managed.

Most people with frozen shoulder regain much or all of their shoulder movement and have less pain as they recover, allowing them to return to their usual activities. About 80% of people recover near-normal or normal shoulder function with proper care. Some may have mild stiffness or discomfort that lasts longer, especially if they have diabetes or thyroid problems.

When surgery is needed, it usually leads to good outcomes if followed by dedicated physical therapy. Even without treatment, frozen shoulder often improves over time, though recovery may be slower and some loss of motion may remain.

“Fortunately, most cases of frozen shoulder do not require surgical treatment, however, patients should consult a surgeon if symptoms persist for six to 12 months despite consistent nonsurgical treatment like physical therapy, home exercises, and medication,” says Kenneth Donohue, MD, MS, chief of Shoulder Reconstruction for Yale Medicine and an expert in complex shoulder, elbow, wrist, and hand surgery.

Yale Medicine prioritizes educating patients about adhesive capsulitis and empowering them to create an exercise plan, says Robin Raju, DO, a Yale Medicine physiatrist. “We encourage patients to maintain a positive mindset, even if their recovery is slow in some cases. Additionally, we recognize the significant psychological impact that a prolonged recovery process can have,” he says. “Our team includes orthopedic surgeons, non-operative musculoskeletal physicians (physiatrists), psychologists, and physical therapists, all working together to guide you through your treatment journey.”