Frozen shoulder (adhesive capsulitis) is several times more common in people with diabetes. Estimates vary, but studies often put it at somewhere around 10 to 20 percent of people with diabetes, compared with a few percent of the general population. It is more likely to affect both shoulders, and it often lasts longer and responds more slowly to treatment. If you have diabetes and are considering a steroid injection, expect your blood sugar to rise for a few days afterward.
The reason seems to be how high blood sugar affects the collagen in the joint capsule over time. This page explains that link, what it means for your recovery, and what to watch for.
Key takeaways
- Higher risk: frozen shoulder is several times more common in people with type 1 or type 2 diabetes.
- Both sides: it is more likely to affect both shoulders, at the same time or one after the other.
- Longer course: it often lasts longer and can leave more lasting stiffness than in people without diabetes.
- Likely reason: high blood sugar binds to collagen in the capsule, making it stiffer and slower to remodel.
- Steroid injections: they can raise blood sugar for a few days, sometimes longer. Plan extra monitoring with your diabetes team.
- Sometimes the first sign: frozen shoulder occasionally appears before diabetes is diagnosed, so doctors may test blood sugar.
Where are you right now?
- New shoulder pain and stiffness: read “Why diabetes raises the risk”, and ask whether your blood sugar control has changed recently.
- Months in and progress is slow: “Month by month” and “If it isn’t going to plan” cover the longer course.
- Thinking about or just had a steroid injection: read “Steroid injections and blood sugar”.
- Getting back to work or sport: see the “When can I…” table.
Why diabetes raises the risk
Collagen is the main protein in the shoulder capsule. When blood sugar runs high over months and years, sugar molecules attach to collagen and form cross-links, known as advanced glycation end products. These make the tissue stiffer and less able to remodel. The capsule then seems more prone to the inflammation and thickening of frozen shoulder, and slower to loosen once it has.
The same process is thought to play a part in other stiff-tissue conditions that are more common with diabetes, including some that affect the elbow, wrist or hand.
Steroid injections and blood sugar
A steroid injection into the shoulder is often used in the painful stage. For people with diabetes:
- Blood sugar often rises: typically within a day, and usually settling within a few days. Some people see raised readings for a week or more.
- Plan ahead: talk to your diabetes team before the injection about checking more often and what to do if readings run high.
- Insulin users: may need a temporary adjustment, which your doctor or diabetes team should guide.
- Repeat injections: the number is usually limited, partly for this reason.
The diabetes does not change what the shoulder needs. It changes how long you need to keep giving it.
Month by month
These are typical ranges. With diabetes, each stage often runs toward the longer end.
- Freezing, often lasting 2 to 9 months: pain builds, often at night; turning the arm outward and reaching behind your back go first.
- Frozen, often lasting 4 to 12 months or longer: pain eases, stiffness peaks.
- Thawing, often lasting 6 months to 2 years or more; with diabetes, often running to month 36: movement returns slowly. With diabetes this stage is often longer.
- After three years: many people have most of their movement back, but lasting stiffness is more common with diabetes.
Where else this could be coming from
- Rotator cuff problems: also more common with diabetes. Lifting the arm yourself hurts or feels weak, but someone else can often move it further.
- Calcific tendinitis: sudden, severe pain from a calcium deposit in a tendon, seen on X-ray or ultrasound.
- Neck problems: pain across the shoulder blade or top of the shoulder that changes with neck movement, sometimes with tingling into the arm.
- Nerve changes from diabetes: burning or numbness tends to start in the feet and hands rather than the shoulder.
- Heart: left shoulder pain with chest pain, breathlessness or sweating. People with diabetes can have heart symptoms that feel less typical.
Is this normal?
- “Both shoulders are going.” More common with diabetes. The second side often starts while the first is in a later stage.
- “It is taking longer than people said.” Expected. The ranges for people with diabetes run longer.
- “My readings jumped after the injection.” A rise for a few days is common. Follow your diabetes team’s advice if readings stay high.
- “Will better control speed it up?” Good control is worth aiming for, for many reasons. It has not been clearly shown to shorten an episode already underway.
If it isn’t going to plan
It is month ten. The bra clasp, the back pocket and the seatbelt have all become one-armed jobs, and someone told you it would be gone by now. The thought in your head is that if it was going to loosen, it would have.
With diabetes, the capsule is slower to remodel, so the waiting game runs longer. Stopping the stretching because progress is slow often means losing the small gains you made. The capsule needs a steady, sustained stretch over many months, and strengthening as movement comes back.
If movement has not changed for two to three months, or night pain still wakes you after six months, get assessed by a physical therapist or your doctor. Questions to ask:
- Stage: which stage am I in, and how should my program change?
- Measurement: which movements will we track, and how often?
- Options: with my diabetes, which treatments are suitable, and what is the plan for blood sugar if I have an injection?
- Other shoulder: what should I look out for on the other side?
When can I…
| Activity | Typical range |
|---|---|
| Sleep on that side | Often not until late in the frozen stage or into thawing; often later with diabetes |
| Drive | Usually possible throughout if you can steer and reach the seatbelt safely |
| Reach overhead | Usually limited for many months; often returns last |
| Lift | Light loads close to the body usually manageable; overhead lifting often waits for thawing |
| Desk work | Usually possible throughout with the arm supported by your side |
| Manual work or sport | Overhead and throwing tasks often limited until well into thawing |
If you have had surgery, your surgeon’s protocol comes first.
Call your local emergency number or go to the emergency department if
- Chest symptoms: shoulder or arm pain with chest pressure, breathlessness, sweating, nausea or jaw pain.
- Very high or very low blood sugar: confusion, drowsiness, vomiting, rapid breathing, or a fruity smell on the breath.
See a doctor today if
- Hot, swollen joint: the shoulder is red, hot or swollen, or you have a fever, especially after an injection.
- Readings will not settle: blood sugar stays well above your usual range for more than a day or two after an injection.
Get it checked soon if
- New thirst or tiredness: you do not have a diabetes diagnosis but notice thirst, passing more urine, or tiredness alongside a stiff shoulder.
- Second shoulder: the other shoulder starts to ache and stiffen.
- Unassessed: a stiff, painful shoulder that is not easing after 2 to 4 weeks.
More on this area: shoulder conditions.
With diabetes, plan for a longer course and keep giving the shoulder what it needs.
Written by Louise Yow, Neck & Shoulder Physio.