Mike: Hello, I'm Mike Clarke, podcast editor for the Cochrane Library. Carpal tunnel syndrome is a common condition that affects people worldwide. There are several Cochrane reviews and these were added to in February 2023 with a new review of corticosteroid injections. Here's lead author, Nigel Ashworth from the University of Alberta in Canada, to tell us about the findings.

Nigel: Carpal tunnel syndrome causes pain, tingling, numbness, and even weakness in the hand and fingers. It occurs when the median nerve in the wrist becomes irritated. As many as 1 in 5 people are affected, with the vast majority being women. The good news is that corticosteroid injections have shown promise in alleviating the symptoms and improving hand function.
Corticosteroids are drugs that reduce inflammation and swelling. When injected into the carpal tunnel, these injections can provide relief for individuals with mild to moderate carpal tunnel syndrome. And the best part? They are more cost-effective than surgery.
But how effective are these injections, and how long do their effects last? To answer these questions, we analyzed 14 relevant studies, involving 639 participants from hospital-based clinics across North America, Europe, and the Middle East.
Our findings revealed that local corticosteroid injections into the wrist likely improve symptoms and hand function for up to six months. These injections may also enhance nerve conduction and improve quality of life over this time period. Furthermore, they may reduce the need for surgery, at least in the first year. It's also important to note that serious complications from these injections were rare, although not all studies reported on them.
However, there are limitations in the evidence. The studies primarily included individuals with mild to moderate carpal tunnel syndrome and excluded those with underlying conditions such as arthritis or diabetes. As a result, we cannot definitively determine the effectiveness of corticosteroid injections in people with severe forms of the disease or comorbidities.
In summary, corticosteroid injections into the wrist are likely to provide relief and improve hand function for up to three months in people with carpal tunnel syndrome. They may also lead to improved nerve conduction and a reduced need for surgery. While side effects are rare, it's important that any decision about their use is done with a consultation with a healthcare professional for an individualized assessment.

Mike: If you would like to learn more about the current evidence, the review is available online at Cochrane Library dot com. If you go to the website and search 'steroid injections for carpal tunnel' you'll see a link to it.