Methylprednisolone injections improve carpal tunnel syndrome short-term and may reduce the likelihood of a patient requiring surgery, shows a comparative study.
The Swedish study aimed to assess the efficacy of local methylprednisolone injections in adults with carpal tunnel syndrome (CTS) who had no previous steroid injections over a year. There were three groups of 37 patients, randomised to receive either 80mg of methylprednisolone, 40mg of methylprednisolone, or placebo. The patients and the surgeons were blinded in the study. The primary end-point was the change in CTS symptom severity at 10-weeks (range one to five) and the rate of surgery at one year.
Improvements in CTS symptom severity scores at 10-weeks were significantly greater in patients who received 80mg of methylprednisolone and 40mg of methylprednisolone, compared with those who received placebo. There was a difference in from baseline of -0.64 and -0.88 in the 80mg methylprednisolone and 40mg methylprednisolone groups at 10 weeks, respectively, but there were no significant differences at one year. The one-year rates of surgery were 73%, 81% and 92% in the 80mg methylprednisolone, 40mg methylprednisolone, and placebo. Compared with patients who received placebo, patients who received 80mg of methylprednisolone were less likely to have surgery (OR 0.24). With time to surgery incorporated, both the 80- and 40mg methylprednisolone groups had a lower likelihood of surgery (HR 0.46 and 0.57 respectively).
What this means for GPs
The researchers noted that their results show that ‘methylprednisolone reduces symptoms and rate of surgery, but three of four patients still had surgery within one year’. They advise that ‘future research should explore how to obtain a consistent durable effect’ and that the goal is ‘to find a medical treatment that effectively resolves carpal tunnel syndrome without the need to divide the transverse carpal ligament’.