What helps a frozen shoulder? A steroid shot and exercise, not the operating theatre

A frozen shoulder — adhesive capsulitis — is a shoulder that becomes painful and then progressively stiff as the capsule around the joint thickens and contracts. It is notorious for two things: it hurts for a long time, and it tends to resolve eventually whatever you do. That second fact is what makes the treatment evidence so useful, because it sets a high bar: any intervention has to beat a condition that mostly gets better on its own. The interventions that clear that bar are the cheap ones.

Surgery is no better than physiotherapy plus a shot

The most important recent trial is UK FROST, published in The Lancet in 2020. It randomly assigned 503 adults with primary frozen shoulder, referred to secondary care, to one of three treatments: manipulation under anaesthesia, arthroscopic capsular release (both surgical, both under general anaesthesia), or early structured physiotherapy with a steroid injection [s1].

At 12 months, the Oxford Shoulder Score (0 to 48, higher is better) was 38.3 (95% confidence interval 36.9 to 39.7) after manipulation, 40.3 (38.9 to 41.7) after capsular release, and 37.2 (35.3 to 39.2) after physiotherapy [s1]. The trial had set a target difference of 5 points between physiotherapy and either operation; every difference came in below that — 3.06 points between capsular release and physiotherapy, and just 1.05 points between manipulation and physiotherapy [s1]. The conclusion was that none of the three was clinically superior [s1]. Surgery also carried the risk: eight serious adverse events with capsular release against two with manipulation, and manipulation was the most cost-effective option [s1]. For most people, in other words, the expensive theatre route buys nothing over the injection-and-exercise route.

The one intervention that consistently wins short-term

If surgery is not the answer, what is? A systematic review and network meta-analysis in JAMA Network Open pooled 65 eligible studies with 4097 participants [s2]. Out of everything tested, only one intervention stood out as both statistically and clinically superior in the short term: intra-articular corticosteroid injection. Against no treatment or placebo it reduced pain by a mean of 1.0 point on the visual analogue scale (95% CI -1.5 to -0.5) [s2]. The authors' takeaway was that early use of intra-articular steroid, in a frozen shoulder of less than a year's duration, is associated with better outcomes — and that it should be paired with a home exercise programme to maximise recovery [s2]. Of the 65 studies, 39 with 2736 participants fed the network meta-analysis, and against that breadth of comparisons the steroid injection was the intervention that separated itself from the pack [s2].

Where physiotherapy and gadgets sit

Physiotherapy is not a stand-alone magic bullet, but it is the essential partner to the injection. A Cochrane review of manual therapy and exercise pooled 32 trials with 1836 participants [s3]. Its best single comparison, of moderate quality, found that six weeks of manual therapy and exercise produced less improvement at seven weeks than a glucocorticoid injection: the mean change in pain was 58 points on a 100-point scale with the injection versus 32 points with manual therapy and exercise [s3]. Treatment success was reported by 46% of the manual-therapy group against 77% of the injection group (risk ratio 0.6; 95% CI 0.44 to 0.83) [s3]. That does not make exercise worthless — it makes it the thing you do alongside the shot and as it wears off.

The passive machines fare worst. A separate Cochrane review of electrotherapy modalities included 19 trials with 1249 participants and found only low-quality evidence, from a single 40-person trial, that low-level laser therapy for six days might beat placebo [s4]. There is little basis for building treatment around ultrasound, laser or electromagnetic devices.

The honest position

A frozen shoulder is a long, self-limiting nuisance, and the evidence points to a modest, low-cost plan rather than a dramatic one: an early intra-articular steroid injection to cut the pain, a home exercise and mobilisation programme to work alongside it, and patience [s1][s2][s3]. Surgery does not deliver a better shoulder at a year and adds real risk [s1]. The main thing worth resisting is being talked up the ladder of invasiveness for a condition that, given time and the basics, mostly thaws by itself.

This article is informational and is not medical advice.

Sources

• [s1] Management of adults with primary frozen shoulder in secondary care (UK FROST) — The Lancet, 3 October 2020. https://doi.org/10.1016/S0140-6736(20)31965-6
• [s2] Comparison of Treatments for Frozen Shoulder: A Systematic Review and Meta-analysis — JAMA Network Open, 1 December 2020. https://doi.org/10.1001/jamanetworkopen.2020.29581
• [s3] Manual therapy and exercise for adhesive capsulitis (frozen shoulder) — Cochrane Database of Systematic Reviews, 26 August 2014. https://doi.org/10.1002/14651858.CD011275
• [s4] Electrotherapy modalities for adhesive capsulitis (frozen shoulder) — Cochrane Database of Systematic Reviews, 1 October 2014. https://doi.org/10.1002/14651858.CD011324