To the Editor: We read with great interest the recent Medicine by the Numbers by Drs. Neubauer and Alisangco on surgical vs nonsurgical treatments for carpal tunnel syndrome.¹ We agree with their findings and conclusions about the treatment of carpal tunnel syndrome, with one exception: “… evidence is uncertain about whether surgery vs corticosteroid injection results in beneficial long-term clinical improvement….”¹

In 2005, we published a randomized clinical trial comparing local corticosteroid injections vs surgery in treating primary carpal tunnel syndrome (163 wrists).² Follow-up occurred at 3, 6, and 12 months and 2 and 6 years posttreatment.^3,4 At the 6-year follow-up, surgery appeared to be more effective than local corticosteroid injections. The accumulated incidence of therapeutic failure was 11.6% in the surgery group vs 41.8% in the injection group (see figure 1).⁴ Conversely, 58% of patients in the injection group did not need further therapeutic interventions during the 6-year follow-up period.

We believe that these results definitively support the superiority of surgery to local corticosteroid injections for carpal tunnel syndrome in the long term.

In Reply: We appreciate your response and your 2005 study that demonstrated a lower therapeutic failure rate for surgical decompression (11.6%) compared with local corticosteroid injection (41.8%) at 6 years.¹ Notably, 58% of patients in the injection group did not require further intervention during this period, indicating that local corticosteroid injection offers durable benefits for a subset of patients.¹ However, our Medicine by the Numbers focuses on the 2024 Cochrane review of 14 randomized trials of surgery compared with multiple nonsurgical interventions, including splinting, corticosteroid injection, platelet-rich plasma, and multimodal conservative care.^2,3 The review highlights the uncertainty in direct comparisons between surgery and local corticosteroid injection, including for outcomes longer than 3 months. The review concluded that long-term clinical improvement and symptom relief differences between surgery and local corticosteroid injection remain uncertain.³