Prevalence of decompression surgery in patients with carpal tunnel syndrome 8 years after initial treatment with a local corticosteroid injection.

UNLABELLED: Repeated local corticosteroid injections have become a common mode of treatment for carpal tunnel syndrome, despite an existing recommendation that no more than three injections should be given. We studied the clinical outcomes in 254 patients who initially opted for a corticosteroid injection into their carpal canal during 2007. Follow-up records of treatment were obtained for 157 patients of whom 41% had proceeded to surgery by 2015. A mean of 1.9 injections had been given before surgery. In the unoperated group, a mean of two (range 0-12) further injections had been given. The final subjective severity and functional status scores measured using the Boston carpal tunnel questionnaire were significantly lower in the operated than in the unoperated group, but both groups improved significantly from baseline. The differences between the final scores are less than the estimated minimal clinically important difference for these measures. We conclude that repeated steroid injection may be a valid treatment option for some patients with carpal tunnel syndrome.

LEVEL OF EVIDENCE: III.