The clinical treatment benefits of shoulder decompression surgery may be no more effective than no treatment at all, according to new Oxford University research.

Painful shoulders account for 2.4% of all GP consultations in the UK, and can make it difficult to work, drive or get dressed. Decompression surgery is often used to treat people with shoulder impingement, when a tendon rubs and catches in the shoulder joint. The surgery has become increasingly popular and is carried out on approximately 21,000 people a year in the UK.

Newly published in The Lancet journal results from the first placebo-controlled trial in arthroscopic shoulder surgery suggest that decompression surgery may not be as effective as first thought. The findings have revealed that the surgery is no better at relieving pain than a placebo and that while both options were fractionally more effective at treating pain than having no surgery at all, the differences were minimal and unlikely to offer noticeable relief.

Conducted by researchers from the Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, with the support of the British Elbow and Shoulder Society (BESS), the study findings have fuelled doubts around the value of the operation and the authors recommend that patients considering the operation should be notified of these results, so that they can make an informed decision about the best treatment for them.

Co-chief investigator professor Andrew Carr, National Institute of Health Research (NIHR) Biomedical Research Centre, University of Oxford, said: “Over the past three decades, patients with this form of shoulder pain and clinicians have accepted this surgery in the belief that it provides reliable relief of symptoms, and has low risk of adverse events and complications. However, the findings from our study suggest that surgery might not provide a clinically significant benefit over no treatment, and that there is no benefit of decompression over placebo surgery.”

Co-chief investigator professor of musculoskeletal sciences David Beard added: “Our findings call into question the value of shoulder decompression surgery for this group of patients, and should be communicated to patients and doctors considering this type of surgery. In light of our results, other ways to treat shoulder impingement could be considered, such as painkillers, physiotherapy and steroid injections.”

The study involved 313 patients suffering persistent pain and symptoms for at least three months despite receiving physiotherapy and steroid injections. 51 surgeons in 32 hospitals in the UK took part in the trial and patients were randomised to receive one of three different treatment options, decompression surgery, placebo surgery or no treatment all.

Decompression surgery is a keyhole surgery that involves removing a small area of bone and soft tissue in the shoulder joint to open up the joint and prevent rubbing or catching when the arm is lifted. In the placebo surgery, surgeons conducted a procedure to look inside the joint where the joint was inspected but no tissue was removed.

Both surgeries were completed as keyhole procedures to ensure that patients were not aware of which surgery they had had. Surgery participants also had one to four physiotherapy sessions afterwards, while those having no treatment only had a check-up appointment three months after the start of the trial.

At six and 12 months post trial participants were asked to feedback about their symptoms and level of pain, rating their symptoms from 0-48, (with a higher number meaning less pain). Overall, symptoms diminished in all three groups from the start of the trial. However it was found that decompression surgery offered no greater benefit to shoulder pain than placebo surgery.

The group who did not receive surgery also improved over time, to the point that patients that were treated with surgery were only slightly more improved than those who were not. However, the authors did not find this difference in improvement to be clinically significant and believe that it can be attributed to a number of other factors.

Although the study did not assess the recurrence of pain after a year, the authors note that it is unlikely that one group would show significant improvements over another long-term, when they have not done so in the year post surgery.

Natalie Carter, head of research liaison and evaluation at Arthritis Research UK, comments: “This study suggests that other treatments such as physiotherapy can be just as effective as shoulder surgery, and should be taken into consideration with patients considering surgery and could influence the decisions made by health providers.

“Often shoulder pain can be short-lived, but if you’re experiencing shoulder pain which continues for more than two weeks, or gets worse, speak to your doctor or a physiotherapist in case you have a more complex problem.”

Considering the broader value of the research, Dr Berend Schreurs of Radboud University Medical Center, the Netherlands, said: “The findings send a strong message that the burden of proof now rests on those who wish to defend the standpoint that shoulder arthroscopy is more effective than non-surgical interventions. Hopefully, these findings from a well-respected shoulder research group will change daily practice. The costs of surgery are high, and although the low occurrence of complications might suggest that the surgery is benign, there is no indication for surgery without possible gain.”

The article is titled, “No benefit of arthroscopy in subacromial shoulder pain.”