Hydrodistension or Steroid Injection for Frozen Shoulder?

Written by the LSRI clinical team and medically reviewed by Dr Prashant Sankaye, Consultant MSK Radiologist, on 2 October 2026.

If you have been told you have a frozen shoulder, you may have heard about two injection options: a steroid injection into the joint, or hydrodistension (also called hydrodilatation). Both are done with ultrasound guidance at LSRI, and both have a place. This article explains how each one works, what the research says, and which factors usually point towards one or the other. For more background on the condition itself, see our frozen shoulder guide, and for details of the procedure, see our hydrodistension page.

What is frozen shoulder?

Frozen shoulder (adhesive capsulitis) happens when the capsule, the tough lining that surrounds the shoulder joint, becomes inflamed, thickened and tight. The result is pain and a gradual loss of movement, particularly turning the arm outwards. It is more common in people with diabetes and thyroid problems, and it can follow an injury or a period when the arm could not be moved normally.

Frozen shoulder usually passes through three overlapping stages:

• Freezing (painful) stage: pain builds, often worse at night, and movement starts to reduce. A GP reference source describes this stage lasting up to around nine months.
• Frozen (stiff) stage: pain often settles but stiffness becomes the main problem, typically lasting several months.
• Thawing stage: movement gradually returns, which can take one to three years.

Most people improve over time, but the NHS notes that frozen shoulder can take months or years to get better, and some people are left with some stiffness or discomfort. That long timescale is why many people look for treatment that eases pain and helps them move sooner.

How a steroid injection works

A corticosteroid is a strong anti-inflammatory medicine. Injected into the shoulder joint, it aims to calm the inflamed capsule and reduce pain. Less pain often makes it easier to sleep and to do the stretching exercises that help movement return.

Steroid injections tend to help most in the early, painful stage, when inflammation is at its most active. They are less likely to change stiffness once the capsule has become thickened and contracted. A GP reference source advises that a steroid injection should not be repeated if earlier injections gave little benefit, or once the stiff phase has set in.

How hydrodistension works

Hydrodistension involves injecting a larger volume of fluid, usually sterile saline with local anaesthetic and often a small dose of steroid, into the shoulder joint under ultrasound guidance. The aim is to gently stretch the tight capsule from the inside. Some people feel pressure or an ache as the fluid goes in.

Hydrodistension is not a stand-alone treatment. The stretch it creates is most useful if you follow it with physiotherapy and a home exercise programme, ideally starting within a few days, to hold on to any movement gained.

What does the evidence say?

Research on frozen shoulder is challenging. Trials are often small, use different techniques and doses, and the condition improves naturally over time, which makes comparisons harder. With that in mind, here is what the main reviews and trials suggest:

• Steroid injection early on: a 2020 systematic review and meta-analysis in JAMA Network Open found that injecting steroid into the joint was associated with better short-term results than other non-surgical treatments, with the advantage appearing to last around six months. The authors concluded that early use in frozen shoulder of less than one year’s duration is associated with better outcomes, and that it should be combined with a home exercise programme.
• Hydrodistension compared with steroid injection: a 2023 systematic review in the British Medical Bulletin reported that hydrodistension leads to at least short-lived greater improvements in shoulder disability and outward rotation than a steroid injection alone. The authors were careful to add that the clinical relevance of this remains unclear and that more research is needed.
• Overview of reviews: a 2021 overview of eight meta-analyses in Knee Surgery, Sports Traumatology, Arthroscopy concluded that hydrodistension with steroid gave better short-term pain relief and better medium-to-long-term range of motion than injection or physiotherapy alone. However, it rated the quality of all the included meta-analyses as low or critically low.
• Older Cochrane evidence: a 2008 Cochrane review found short-term benefits of distension with saline and steroid, but said it was uncertain whether it was better than other treatments, and found it may not differ from a steroid injection alone.

The UK FROST trial, published in 2020, is the largest UK trial in this area. It compared early structured physiotherapy (which included a steroid injection into the joint), manipulation under anaesthesia and keyhole capsular release surgery in adults referred to hospital with frozen shoulder. None of the three treatments was clearly better for pain and function at 12 months. FROST did not test hydrodistension, but it does support steroid injection with structured physiotherapy as a reasonable first approach before surgery is considered.

In short: steroid injection has the stronger case for pain in the early stage; hydrodistension may offer a modest extra gain in movement, particularly when stiffness is the main problem and it is followed by physiotherapy. Results vary between people, and the benefits reported in trials are mostly short to medium term.

Which is right for me? Decision factors

The table below summarises the factors Dr Sankaye usually discusses with patients. It is a guide, not a rule, and the decision is always made together after an ultrasound assessment.

If you have diabetes, NHS advice is to check your blood glucose frequently for at least 72 hours after a steroid injection, as levels can rise, particularly in the first 24 to 72 hours.

What to expect at LSRI

Your appointment starts with an ultrasound scan of the shoulder. This helps confirm the diagnosis and rule out other causes of pain, such as a rotator cuff tear or calcific tendinopathy, which may need a different approach. If an injection is appropriate, Dr Sankaye will explain the options and answer your questions before anything is done.

Both procedures are carried out under ultrasound guidance with the skin cleaned and numbed first. A steroid injection takes a few minutes; hydrodistension takes a little longer. Afterwards, the shoulder may feel numb for a few hours, and some people notice a temporary increase in pain for a day or two. We will give you written aftercare advice, including warning signs of infection to look out for, and recommend gentle movement and a plan for physiotherapy.

Frequently asked questions

Is hydrodistension painful?

Local anaesthetic is used, but most people feel pressure or a deep ache as the capsule stretches. This usually eases quickly once the injection is finished. Tell the clinician at any time if you are uncomfortable.

Can I have a steroid injection first and hydrodistension later?

Yes. Many people start with a steroid injection in the painful stage, then consider hydrodistension if stiffness remains the main problem. Dr Sankaye will consider how many steroid injections you have had before recommending further treatment.

Do I still need physiotherapy?

Yes. The research consistently supports combining injection treatment with exercise. After hydrodistension in particular, physiotherapy helps you keep the movement gained.

Will the injection make my frozen shoulder go away?

Injections aim to reduce pain and help movement return while the condition runs its course. They do not work for everyone, and results vary from person to person. We will talk you through realistic expectations for your stage and symptoms.

When would surgery be considered?

If symptoms remain severe despite injections and physiotherapy, referral to a shoulder surgeon to discuss manipulation under anaesthesia or capsular release may be appropriate. We can help arrange this.

Book an appointment

Call 0203 633 5040 or book online. Clinics at Harley Street (W1G 9QJ) and Harrow (HA2 7SJ).

References

1. Challoumas D, Biddle M, McLean M, Millar NL. Comparison of Treatments for Frozen Shoulder: A Systematic Review and Meta-analysis. JAMA Network Open, 2020. https://eprints.gla.ac.uk/225711/1/225711.pdf
2. Poku D, Hassan R, Migliorini F, Maffulli N. Efficacy of hydrodilatation in frozen shoulder: a systematic review and meta-analysis. British Medical Bulletin, 2023. https://academic.oup.com/bmb/article/147/1/121/7231525
3. Lädermann A, Piotton S, Abrassart S, et al. Hydrodilatation with corticosteroids is the most effective conservative management for frozen shoulder. Knee Surgery, Sports Traumatology, Arthroscopy, 2021. https://link.springer.com/article/10.1007/s00167-020-06390-x
4. Buchbinder R, et al. Arthrographic distension for adhesive capsulitis (frozen shoulder). Cochrane, 2008. https://www.cochrane.org/evidence/CD007005_arthrographic-distension-adhesive-capsulitis-frozen-shoulder
5. Rangan A, et al. Surgical treatments compared with early structured physiotherapy in secondary care for adults with primary frozen shoulder: the UK FROST three-arm RCT. Health Technology Assessment (NIHR), 2020. https://www.ncbi.nlm.nih.gov/books/NBK565277/
6. Frozen shoulder. NHS. https://www.nhs.uk/conditions/frozen-shoulder/
7. Hazell T. Frozen shoulder (adhesive capsulitis). Patient.info (professional reference), reviewed 2026. https://patient.info/doctor/orthopaedics/frozen-shoulder-pro
8. Post corticosteroid injection advice for people with diabetes. The Dudley Group NHS Foundation Trust, 2025. https://www.dgft.nhs.uk/pil/post-corticosteroid-injection-advice-for-people-with-diabetes/