What exactly is frozen shoulder?

Frozen shoulder occurs when the capsule surrounding the shoulder joint becomes inflamed, thickened, and tight. This leads to progressive pain and loss of shoulder motion. Unfortunately, recovery can be slow, taking months to years. But physical therapy can help manage pain, maintain and improve mobility, and improve function throughout the process. 

Frozen shoulder affects women disproportionately, particularly between the ages of 40 and 60. Sound familiar? Those are also the years when many women are navigating perimenopause and menopause.

Hormonal changes have been proposed as one possible reason women may become more susceptible to conditions such as frozen shoulder during midlife. Research is still evolving, so we can’t say that menopause causes frozen shoulder, but the association is important for women to know about.

Wonder why you’re just hearing this now?  It took a while for the medical community to look past the shoulder. 

In the 1930s, “frozen shoulder” was popularized to described a painful, stiff shoulder that often had no obvious cause. This became known as idiopathic frozen shoulder. Idiopathic is a medical term that means “no specific underlying cause has been identified” despite proper medical testing and evaluation of a disease, condition, or symptom.  No one understood why it happened and there wasn’t much urgency to study this condition, as it often resolved on its own.

In the 1940s,  “adhesive capsulitis” replaced idiopathic frozen shoulder. It was introduced because doctors believed inflammation led to adhesions and tightening of the shoulder’s joint capsule.

In the 1950s, physicians recognized that frozen shoulder occurred more frequently in middle-aged women, but research focused primarily on what was happening inside the shoulder and not why women were affected more often. Frozen shoulder was largely treated as an orthopedic problem.  Not anything else. Doctors recognized associations with conditions such as diabetes and thyroid disease, but many cases still seemed to occur with no explanation. 

Finally, researchers have looked beyond the shoulder at metabolic, inflammatory and hormonal influences. The higher incidence in women around midlife has generated particular interest in estrogen and menopause. Why was this overlooked for so long? Because menopause was not routinely considered a musculoskeletal issue. Estrogen research concentrated on hot flashes, reproductive health, cardiovascular disease and osteoporosis – not tendons, fascia, joint capsules and connective tissue. Plus, perimenopause is even more difficult to study.  This phase happens gradually, with women entering the transition at different ages, with fluctuating hormone levels and varying symptoms. Showing that changing estrogen levels actually cause capsular changes requires much more research and data than simply noticing that the two occur around the same time. 

The important turning point appears to be 2022. Duke researchers presented (what they described as) the first known study specifically evaluating hormone replacement therapy and adhesive capsulitis in menopausal women. 

Their results were intriguing: among 1,952 menopausal women, frozen shoulder occurred in 7.7% of women not taking HRT versus 4.0% of women taking HRT. Women not taking HRT had about twice the odds of frozen shoulder, although the result did not reach statistical significance, so it can’t establish that estrogen prevents frozen shoulder. 

So how do you know if your shoulder is freezing? This is the first phase, followed by frozen, and thawing.  

You may gradually notice:

• Increasing shoulder pain, especially at night
• Difficulty sleeping on that side
• Trouble reaching behind your back
• Difficulty putting on a bra or jacket
• Loss of overhead motion
• Increasing stiffness that doesn’t seem to improve

What can you do? 

Don’t wait until it is frozen. The early phase can be very painful and highly irritable. That’s different from the later phases, when stiffness tends to dominate.  As soon as you feel any/some of the symptoms above, reach out to your doctor or physical therapist. to determine whether this is actually frozen shoulder (versus rotator cuff pathology, arthritis, cervical radiculopathy, etc). Early diagnosis is particularly useful when pain and loss of motion are starting together. 

• Keep the shoulder moving gently. Frequent, comfortable movement is generally preferable to complete rest. Think gentle range of motion, not aggressive stretching.
• Don’t force painful end ranges. In a highly irritable early frozen shoulder, repeatedly pushing hard into pain can aggravate symptoms. The amount and intensity of stretching should match the shoulder’s irritability.
• Use pain as a guide. Gentle arm swings, table/wall slides, assisted elevation, and comfortable external-rotation exercises may be appropriate, but be careful what you read online. Protocols are evolving with current research. 
• Address sleep early. Sleeping on the opposite side with the affected arm supported by a pillow can be more comfortable. Some people do better with the arm supported in front of them rather than hanging downward.
• Ask about pain control. If pain is significantly limiting sleep or movement, discuss appropriate medications or other options with your physician. 

The connection between frozen shoulder and hormones is being studied at the University of California – San Francisco. UCSF is currently testing the effectiveness of hormone replacement therapy in addition to standard treatment vs. standard treatment alone to treat frozen shoulder in peri- and postmenopausal women. Want to know more? Here is the link to the clinical trial.  

• Hands-on manual therapy to improve joint and soft-tissue mobility
• Gentle, targeted stretching appropriate for your stage of recovery
• Strengthening to maintain shoulder and upper-body function
• Pain-management strategies to make sleeping and daily activities easier
• A personalized home program so you know what to do—and what not to do

Other medical treatment options may include anti-inflammatory medication, corticosteroid injections, or other interventions depending on the severity and stage of the condition.

The Bottom Line

Frozen shoulder can be frustrating, but you don’t simply have to wait it out. If you’ve noticed unexplained shoulder pain or increasing stiffness—particularly if you’re in your 40s, 50s, or going through the menopause transition—it’s worth having your shoulder evaluated.