Carpal Tunnel: Injection May Decrease Need for Surgery

Lilian White, MD
Posted on October 7, 2024

Carpal tunnel syndrome (CTS) is one of the most common hand conditions treated by family physicians, affecting an estimated 4% of the population. The incidence of CTS increases with age, with a typical onset around 30 years of age. A median of 28 days of work tends to be lost by those with CTS, making it an essential consideration for employee health. Risk factors for the development of CTS include elevated body mass index, female sex, pregnancy, hypothyroidism, diabetes, and repetitive motion of the wrist.

The cost of surgery for the treatment of CTS has been estimated to be in excess of $2 billion per year in the United States. Less expensive treatment options for CTS include local corticosteroid injection and splinting; however, the benefit of these interventions has been debated. A Cochrane review article evaluated the effectiveness of local corticosteroid injection vs placebo for CTS for mild-to-moderate CTS. The meta-analysis included 994 study participants. At 6 months following local corticosteroid injection, participants continued to note improvements in quality of life, symptoms, and function. At 1 year after local corticosteroid injection, participants had a slightly reduced need for surgery.

Another study demonstrated that success of treatment of CTS with splinting and corticosteroid injection appears to be highest in those patients without sensory impairment and with onset of CTS within the past 3 months. Local corticosteroid injection is overall well tolerated. One of the most common adverse effects of injection is mild-to-moderate post-injection site pain that may last up to 2 weeks. 

The American Academy of Orthopedic Surgeons notes in its 2024 guideline on the management of carpal tunnel syndrome that local corticosteroid injection does not provide long-term improvement, for which surgery is the preferred treatment. There does not appear to be a significant difference in symptom improvement in patients who undergo mini-open vs endoscopic surgery for CTS, and both are considered both are considered qually effective. Endoscopic treatment may be associated with higher costs and complications compared with mini-open surgery depending on the treatment setting. At 1 year, the risk of requiring a revisionary surgery is almost three time higher in those receiving endoscopic repair compared with mini-open repair. However, the absolute risk or revision surgery was found to be overall low for endoscopic repair at approximately 2%.

Injection of platelet-rich plasma (PRP) has also been proposed as a nonsurgical treatment option for CTS. A meta-analysis and systematic review demonstrated that PRP may be beneficial for the treatment of CTS. PRP was found to be less effective for the treatment of CTS compared with corticosteroid injection. PRP injection is a relatively safe procedure with no serious complications appreciated in the current literature.

Although the natural history of CTS was previously thought to result in continued worsening of nerve impingement, it has been found that up to 50% of patients with nonsevere symptoms may spontaneously improve. Many other patients experience a stabilization of symptoms over time. Older age and a longer duration of symptoms of are risk factors for progression of CTS.

Local corticosteroid injection for the treatment of CTS is overall a reasonable treatment option that can be offered in the office setting. Specific consideration may be given for those patients wishing to delay or reduce the risk of surgery or in those patients with a need for improvement in symptoms, function, and quality of life who are not surgical candidates. Additional information on the diagnosis and treatment of CTS may be found in a recent AFP article, Carpal Tunnel Syndrome: Rapid Evidence Review.