Shoulder Embolization vs. Cortisone Injections and Hydrodilatation

For most people with frozen shoulder, a cortisone (steroid) injection comes well before any talk of embolization. Some are also offered hydrodilatation, a high-volume injection that stretches the joint capsule from the inside. This article explains how these injections compare with shoulder embolization, what the research says about each, and why they are usually used in sequence rather than as competitors.

Three different approaches

What the research says about cortisone injections

Steroid injection into the joint is the best-supported early treatment for frozen shoulder. A 2020 meta-analysis in JAMA Network Open reviewed 65 studies with 4,097 participants. Of all the treatments examined, only intra-articular steroid injection showed both statistical and clinical superiority in the short term, for pain and for function. The benefit was best when given within the first year of symptoms and combined with a home exercise program.

A Cochrane review compared steroid injection with a combination of manual therapy and exercise in one randomized trial. At 7 weeks, 77% of patients who received the injection reported treatment success, compared with 46% of those who had manual therapy and exercise. By 6 and 12 months, the differences were no longer clinically important. Adverse events were similar in both groups.

In short, cortisone is good at bringing pain down early, especially in the painful early phase. Its effect is temporary, and it does not always stop the condition from running its course.

What the research says about hydrodilatation

A Cochrane review of 5 trials with 196 people found evidence that hydrodilatation with saline and steroid provides short-term benefits in pain, range of motion, and function, though it was uncertain whether it was better than other treatments. In the best-quality trial, it outperformed placebo at 3 weeks. A 2023 meta-analysis in the British Medical Bulletin concluded that hydrodilatation leads to at least temporarily greater improvement in disability and outward rotation than a steroid injection alone, while noting that its long-term clinical importance is still unclear.

Hydrodilatation may be offered when stiffness is a bigger issue than pain, since it physically stretches the capsule.

Where embolization fits

Shoulder embolization has been studied in people for whom these treatments were not enough. Typical study patients had months of symptoms despite medication, physical therapy, and often injections. A 2026 meta-analysis of 12 single-arm studies with 329 shoulders found large average improvements in pain, motion, and function after embolization, with no severe adverse events reported. Because these studies lacked comparison groups, they do not show whether embolization works better than another injection would have.

That question is now being tested directly. A randomized, triple-masked trial in Taiwan is comparing embolization with a corticosteroid injection in 94 patients with frozen shoulder, with results expected around 2030. Until then, embolization is best thought of as a next step when injections have not given lasting relief, not as a replacement for them. If you are unsure which category you are in, our guide to who is a candidate for frozen shoulder embolization can help.

This article is part of our Embolization Guide.

Practical differences to consider

Repeat injections

Many doctors limit how many steroid injections they give into the same joint over a period of time. If you have already had several injections with only short relief, that is often the point when other options, including embolization, hydrodilatation, or surgery, are discussed.

Diabetes

Frozen shoulder is about 5 times more common in people with diabetes, according to a 2016 meta-analysis. Steroid injections can temporarily raise blood sugar, which matters for people with diabetes. Embolization does not involve a steroid, though people with diabetes may have less complete results, as seen in one small 2024 study.

The procedure itself

A steroid injection takes minutes in the office. Hydrodilatation is usually done with imaging guidance and may take longer. Embolization is a catheter procedure that, in one 2024 study, took a median of about 33 minutes, followed by observation before going home. It involves contrast dye and carries small catheter-related risks, such as wrist bruising.

Matching the treatment to your stage

The American Academy of Orthopaedic Surgeons describes three stages of frozen shoulder. The freezing stage, when pain is at its worst, typically lasts 6 weeks to 9 months. The frozen stage, when stiffness dominates, lasts about 4 to 6 months. Thawing, the slow return of motion, can take 6 months to 2 years.

• Freezing stage: this is when a steroid injection is most likely to help, in line with the 2020 meta-analysis finding that early use, within the first year, gave the best results.
• Frozen stage: stretching, physical therapy, and sometimes hydrodilatation become more important because the capsule is tight.
• Prolonged pain at any stage: if pain, especially at night, persists for months despite injections and therapy, that is the group studied for embolization.

Real life is rarely this tidy, and stages often overlap. Still, knowing roughly where you are helps explain why your doctor may recommend one option over another.

Questions to ask your doctor

• How many steroid injections have I had, and how long did each one help?
• Is my main problem pain or stiffness right now?
• Would hydrodilatation be a reasonable next step before anything more involved?
• What would make me a good or poor candidate for embolization?
• How would my diabetes, if I have it, change your recommendation?

Using them together

These options are not mutually exclusive. A common path looks like this:

1. Early frozen shoulder: steroid injection plus a home exercise program
2. Ongoing stiffness or partial relief: physical therapy, possibly hydrodilatation or a repeat injection
3. Persistent pain despite these: discussion of embolization or surgery, based on whether pain or stiffness dominates

Physical therapy runs through all of these stages. See shoulder embolization versus physical therapy for how exercise fits in, and embolization versus surgery for the surgical options.

Bottom line

Cortisone injections have the strongest evidence for early, short-term relief of frozen shoulder pain. Hydrodilatation adds a short-term boost in motion for some patients. Shoulder embolization is a promising option for pain that persists after these, supported so far by encouraging but uncontrolled studies. Whichever path you take, keeping up with your home exercises gives each treatment its best chance to work. For a fuller picture, visit the embolization guide or our shoulder embolization overview.

Frequently Asked Questions

Should I try a cortisone shot before shoulder embolization?

In most cases, yes. Steroid injection has the strongest evidence for early frozen shoulder pain, and shoulder embolization has mainly been studied in people who did not improve enough with conservative care.

Is hydrodilatation better than a cortisone injection?

A 2023 meta-analysis found hydrodilatation gave at least temporarily greater improvements in disability and outward rotation than steroid injection alone, but its long-term importance is unclear.

Is embolization being compared with steroid injections?

Yes. A randomized, triple-masked trial in Taiwan comparing the two in 94 patients with frozen shoulder began recruiting in 2026, with results expected around 2030.

How many cortisone shots can I have in my shoulder?

There is no single rule, and doctors set their own limits. If repeated injections give only short relief, ask about other options.

Keep Reading

• Shoulder Embolization in Manhattan
• Shoulder Embolization vs. Physical Therapy: Competitors or Partners?
• Shoulder Embolization vs. Surgery: MUA and Capsular Release Compared
• Frozen Shoulder: Causes, Symptoms, and Stages Explained
• Frozen Shoulder Embolization: Am I a Candidate?
• How Long Does Shoulder Embolization Last?
• Embolization Guide: knee, heel, shoulder, elbow and hip

Sources

1. Challoumas et al., JAMA Netw Open, 2020 — comparison of treatments for frozen shoulder: systematic review and meta-analysis
2. Page et al., Cochrane Database Syst Rev, 2014 — manual therapy and exercise for adhesive capsulitis
3. Buchbinder et al., Cochrane Database Syst Rev, 2008 — arthrographic distension (hydrodilatation) for adhesive capsulitis
4. Poku et al., Br Med Bull, 2023 — efficacy of hydrodilatation in frozen shoulder: systematic review and meta-analysis
5. Allaw et al., J Vasc Interv Radiol, 2026 — systematic review and meta-analysis of embolization for adhesive capsulitis (12 studies, 329 shoulders)
6. ClinicalTrials.gov NCT07696923 — embolization vs corticosteroid injection for frozen shoulder (recruiting)
7. Zreik et al., Muscles Ligaments Tendons J, 2016 — adhesive capsulitis and diabetes: a meta-analysis of prevalence
8. Lanciego et al., J Vasc Interv Radiol, 2024 — midterm outcomes of embolization for adhesive capsulitis (20 patients)
9. American Academy of Orthopaedic Surgeons, OrthoInfo — Frozen Shoulder

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.