Frozen shoulder, known medically as adhesive capsulitis, makes the shoulder painful and then progressively stiff, often for no obvious reason. It can make simple things like fastening a bra, reaching into a back pocket, or sleeping on your side feel impossible. Understanding what is happening inside the joint, who is at risk, and how the condition typically unfolds can make it far less frightening and help you choose the right care at the right time.
What frozen shoulder is
The shoulder joint is surrounded by a capsule of connective tissue that normally stretches and folds as you move. In frozen shoulder, this capsule becomes inflamed, thickens, and tightens. The space inside the joint shrinks, and motion becomes limited in every direction, both when you try to move the arm yourself and when someone else tries to move it for you. That second point, loss of passive motion, is one of the features that helps doctors tell frozen shoulder apart from a rotator cuff problem.
Researchers now think inflammation and new blood vessel growth play an important role. In a 2014 Japanese study, all 7 patients with frozen shoulder had abnormal new vessels near the front of the capsule, an area called the rotator interval. A 2023 study using PET scans found clear signs of chronic inflammation in the affected shoulder compared with the healthy one. These findings are the basis for newer treatments such as shoulder embolization.
Who gets frozen shoulder
Frozen shoulder affects roughly 2% to 5% of the general population, according to a 2026 review. The American Academy of Orthopaedic Surgeons notes that it most commonly affects people between 40 and 60 and occurs more often in women. In a 2008 Oxford study of 223 patients, the average age when symptoms began was about 53, and women outnumbered men about 1.6 to 1.
Risk factors
- Diabetes. This is the strongest known link. A 2016 meta-analysis found people with diabetes were about 5 times more likely to develop frozen shoulder. About 13% of people with diabetes had it, and about 30% of people with frozen shoulder had diabetes. The authors suggested screening for diabetes in people diagnosed with frozen shoulder.
- Thyroid disease. The AAOS lists thyroid conditions as a risk factor.
- A period of immobilization. Stiffness can follow surgery, a fracture, or other injury, especially when the arm was kept still for a time. Doctors sometimes call this secondary stiff shoulder.
In many people, frozen shoulder starts with no clear trigger at all. This is called primary or idiopathic frozen shoulder.
Primary versus secondary stiffness
The distinction matters because the causes and treatments can differ. A 2021 Spanish study of 25 people with secondary stiff shoulder gives a sense of this group: 56% developed stiffness after surgery and 44% after an injury, all had been through a period of immobilization, and their shoulders had been stiff for a median of 12 months before treatment. If your stiffness followed an operation or a fracture, make sure your doctor knows the full history, since it can change which options make sense.
Symptoms
- A dull, aching pain in the outer shoulder or upper arm, which the AAOS notes is typically worse early on and when you move the arm
- Pain at night, often enough to wake you or prevent sleeping on the affected side
- Gradual loss of motion, especially reaching overhead, reaching behind your back, and rotating the arm outward
- Difficulty with daily tasks such as dressing, washing your hair, or reaching for a seatbelt
Night pain is so typical that it has been a main outcome in several treatment studies.
The three stages
| Stage | Typical length (AAOS) | What it feels like |
|---|---|---|
| Freezing | 6 weeks to 9 months | Pain builds, especially at night, and motion starts to slip away |
| Frozen | 4 to 6 months | Pain may ease, but stiffness peaks and daily tasks become very difficult |
| Thawing | 6 months to 2 years | Motion slowly returns toward normal or near normal |
These stages are a useful guide, but they do not predict exactly how your shoulder will behave. They often overlap, and the timing varies a great deal between people.
Questions about your treatment options? Dr. Fox can help.
Book a ConsultationThis article is part of our Embolization Guide.
Does frozen shoulder go away on its own?
Often, but not always completely. The AAOS states that frozen shoulder generally gets better over time without surgery, although it may take up to 3 years. The long-term picture is more mixed:
- In the 2008 Oxford study, an average of 4.4 years after symptoms began, 59% of patients had normal or near-normal shoulders, while 41% had some lasting symptoms. Most of these were mild, but 6% had severe pain and loss of function. People whose symptoms were most severe at the start tended to do worst.
- A 2017 systematic review challenged the idea that frozen shoulder reliably passes through its stages to full recovery without treatment. It found most improvement happened early rather than late.
- In the Oxford study, 20% of patients had symptoms in both shoulders at some point, but no one had it return in the same shoulder.
Why early care matters
Because frozen shoulder can improve with time, some people are told to simply wait it out. Waiting is a reasonable choice for some, but there are good reasons not to ignore it. A 2020 meta-analysis of 65 studies found that a steroid injection given within the first year of symptoms, combined with home exercises, was linked with better outcomes. Getting a clear diagnosis early also rules out other causes of shoulder pain, and it can uncover undiagnosed diabetes. You can find out more about later-stage options in our guide to who is a candidate for frozen shoulder embolization.
How it is diagnosed
Diagnosis is mainly clinical. Your doctor will measure how far you can move your arm yourself (active motion) and how far it can be moved for you (passive motion). Loss of both points toward frozen shoulder. X-rays help rule out arthritis or fracture. MRI or ultrasound can show capsule thickening and inflammation and check the rotator cuff. Blood tests for diabetes or thyroid problems may be suggested.
Treatment options at a glance
Treatment usually starts simple and steps up if needed:
- Pain relief and physical therapy, with stretching and a home exercise program. See embolization versus physical therapy.
- Steroid injection, which has the strongest evidence for early pain relief, and sometimes hydrodilatation. See embolization versus cortisone injections.
- Procedures for persistent cases, including manipulation under anesthesia, arthroscopic capsular release, or, for some patients with ongoing pain, shoulder embolization. Its evidence is promising but still early. Learn more on our shoulder embolization page and in the embolization guide.
When to see a doctor, and when it is urgent
See a doctor if shoulder pain and stiffness last more than a few weeks, keep you up at night, or limit daily tasks. If you have diabetes or thyroid disease, mention it. Seek urgent care for shoulder or arm pain with chest pressure, shortness of breath, sweating, or jaw pain; a hot, swollen shoulder with fever; or sudden weakness or inability to lift the arm after a fall.
Frequently Asked Questions
What causes frozen shoulder?
The joint capsule becomes inflamed, thickens, and tightens. Often there is no clear trigger. Diabetes, thyroid disease, and a period of immobilization after surgery or injury raise the risk.
How long does frozen shoulder last?
The AAOS describes stages that together can take up to about 3 years. Many people recover well, but in one long-term study 41% had some lasting symptoms, usually mild.
Can frozen shoulder happen in both shoulders?
Yes. In a 2008 study of 223 patients, 20% had symptoms in both shoulders at some point, though it did not return in the same shoulder.
Is frozen shoulder the same as a rotator cuff tear?
No. Frozen shoulder limits motion even when someone else moves your arm, while rotator cuff problems more often cause weakness and pain with lifting. Exam and imaging help tell them apart.
Keep Reading
- Shoulder Embolization in Manhattan
- Frozen Shoulder Embolization: Am I a Candidate?
- How Long Does Shoulder Embolization Last?
- Is Shoulder Embolization Covered by Insurance?
- Is Shoulder Embolization Painful? What to Expect Before, During, and After
- Your Shoulder Embolization Consultation Guide
- Embolization Guide: knee, heel, shoulder, elbow and hip
Sources
- American Academy of Orthopaedic Surgeons, OrthoInfo — Frozen Shoulder
- Leung et al., Skeletal Radiol, 2026 — adhesive capsulitis embolization: a narrative review
- Zreik et al., Muscles Ligaments Tendons J, 2016 — adhesive capsulitis and diabetes: a meta-analysis of prevalence
- Hand et al., J Shoulder Elbow Surg, 2008 — long-term outcome of frozen shoulder (223 patients)
- Wong et al., Physiotherapy, 2017 — natural history of frozen shoulder: a systematic review
- Okuno et al., J Shoulder Elbow Surg, 2014 — pilot study of arterial embolization for adhesive capsulitis (7 patients)
- Shintaku et al., J Shoulder Elbow Surg, 2023 — FDG-PET inflammation changes after embolization in frozen shoulder (15 patients)
- Fernández-Martínez et al., J Vasc Interv Radiol, 2021 — embolization for secondary stiff shoulder (25 patients)
- Challoumas et al., JAMA Netw Open, 2020 — comparison of treatments for frozen shoulder: systematic review and meta-analysis
Medically reviewed by David Fox, MD, FACS, RPVI. This article is general information, not a substitute for a medical evaluation.
Living with joint or tendon pain that hasn’t improved? Schedule a consultation with Dr. David Fox at Fox Vein & Vascular in Manhattan to find out whether embolization is right for you. Call (212) 362-3470 or request an appointment online.
