Surgery achieves better follow-up outcomes than steroids in CTS
MedWire News: Surgical decompression for patients with carpal tunnel syndrome (CTS) is slightly more effective in treating the major symptom of nocturnal paresthesias than steroid injection at 2 year follow up, results of a randomized trial show.
Since steroids were more effective than surgery at 3 month follow up, and efficacy of the two treatments was equal at 1 year, the results suggest that the efficacy of steroid injection diminishes over time.
Clinically, CTS is characterized by signs and symptoms of irritation of the median nerve where it passes under the transverse carpal ligament at the wrist. Affected patients complain of numbness and pain in the hand, and their symptoms typically worsen during nocturnal rest.
There is a trend to use conservative treatments in less symptomatic cases, beginning with splinting and nonsteroidal anti-inflammatory drugs (NSAIDs), and local steroid injection when these fail. Surgical treatment is preferred over conservative therapies for very symptomatic and prolonged CTS.
In a previous paper, José-Luis Andréu (Hospital Universitario Puerta de Hierro Majadahonda, Madrid, Spain) and colleagues demonstrated that steroid injections were as safe and effective as surgery in idiopathic CTS at 1-year follow up.
"The original study has been extended one more year because there is a clinical impression that injections had a greater relapse of symptoms than surgery," the researchers comment in Rheumatology.
In all, 80 wrists were randomly assigned to surgical decompression and 83 wrists to local steroid injection. Two-year follow-up data were available for 55 wrists in the surgery group and 48 wrists in the injection group.
Patients used a visual analog scale (VAS) (0-100: from no symptoms to the most intense symptoms) to assess their level of nocturnal paresthesias in the area of the distribution of the median nerve, their level of diurnal pain, and their overall level of self-perceived functional impairment.
Andréu et al report that, with regard to nocturnal paresthesias at 3-months follow up, more wrists in the injection group than in the surgery group achieved a 20% response (94 vs 75%, respectively).
This advantage vanished at 1-year follow up and in fact, at 2-year follow up, 60% of wrists in the injection group and 69% in the surgery group achieved a 20% response in nocturnal paresthesias. Results for the other two symptom domains (diurnal pain and self-perceived functional impairment) were similar.
Discussing the outcomes, Andréu et al speculate: "Steroids could reverse some pathogenic mechanisms in CTS, like suppression of synovial swelling and/or vascular congestion, with a secondary relief of local ischaemia, resulting in a reduction of the pressure inside the CT.
Theoretically, steroid injection may only provide provisional relief as long as the mechanical restriction persists, while section of the flexor retinaculum should provide greater space for the contents of the CT, and consequently should resolve the problem."
By Andrew Czyzewski