Authors' objectives: The objective of this health technology assessment is to summarize the current knowledge on the efficacy and safety of decompression surgery for carpal tunnel syndrome compared to non-surgical treatments with wrist splinting, combinations of nonsurgical treatments, local corticosteroid injection (steroid injection) and physical therapy (including manual therapy). We planned to analyse outcomes based on pre-treatment severity of carpal tunnel syndrome (mild, moderate, and severe) if reported, to evaluate whether some subpopulations seem to benefit more from surgery than others.

Authors' results and conclusions: We included 10 randomized controlled trials (13 publications) with 960 patients or wrists with carpal tunnel syndrome. Mean age ranged from 41 to 53 years, and 51 to 100% of the participants were females. Seven trials excluded patients with severe carpal tunnel syndrome. All trials were at high risk of bias for at least two domains; lack of blinding of participants and assessors. Some trials had serious methodological concerns. None of the trials reported outcomes according to pre-treatment severity with mild, moderate, and severe carpal tunnel syndrome. Three trials compared surgery with splinting. At 1 year, low-certainty evidence from one trial (downgraded for bias and imprecision) suggested a superior, but small, effect of surgery on symptom severity, daytime paraesthesia, and function. For symptoms, which was considered as the most important outcome by the patient representatives and the project’s clinical experts, patients reported less severity after surgery than after splinting; the standardized mean difference between groups from the intention to treat (ITT) analyses was -0.47 (95% confidence intervals, CI -0.78 to -0.15). Notably, 38% of the patients allocated to splinting had undergone surgery at 1 year. Three trials compared surgery with non-surgical treatments. At 1 year, low-certainty evidence from one trial (downgraded for bias and imprecision) suggested a superior, but small, effect of surgery on symptom severity and hand function, and little or no difference in effect on pain. Mean difference between groups in symptom severity was - 0.33 points (95% CI -0.65 to -0.01). In this trial 44% of the patients allocated to nonsurgical treatment had undergone surgery at 1 year. “As treated” analyses revealed a larger mean difference between groups; -0.84 (95% CI -0.55 to -1.13) points. Two trials compared surgery with steroid injections and three trials compared surgery with manual therapy. We are uncertain of the efficacy of surgery compared to steroid injection and of surgery compared to manual therapy very low-certainty evidence (downgraded for bias and imprecision). Overall, few serious adverse events were reported, but rare adverse events such as complex regional pain syndrome did occur after surgery. The results of our economic evaluation showed that surgery is the most costly treatment at Norwegian kroner (NOK) 11,200 for treatment of patients with mild to moderate carpal tunnel syndrome. The non-surgical treatment alternatives splinting and local steroid injection cost approximately NOK 3,100. We estimated potential cost savings at the national level to be between 14.5 and 27.5 million NOK kroner over five years. Conclusion:

Authors' recommendations: Overall, low-certainty evidence suggests that decompression surgery is slightly more effective than splinting and combinations of non-surgical treatments at 1 year in patients with mild to moderate carpal tunnel syndrome. There is insufficient evidence regarding the efficacy of surgery compared to steroid injections and manual therapy. Overall, few serious adverse events were reported, but small randomized trials are not suitable to make reliable comparisons of adverse events. Surgery is the most costly treatment alternative for patients with mild to moderate carpal tunnel syndrome. An observed regional variation in the provision of surgery in Norway suggests a potential for cost-saving per health region and at the national level if patients with mild to moderate carpal tunnel syndrome are initially treated with the non-surgical alternatives.

Authors' methods: We developed a project plan with input from the external experts and patient representatives. We searched for systematic reviews in the Cochrane Database of Systematic Reviews (Wiley), Epistemonikos (Epistemonikos Foundation), INAHTA (International Network of Agencies for Health Technology Assessment), MEDLINE (Ovid) and Embase (Ovid), and for randomized controlled trials (RCTs) in MEDLINE (Ovid), Embase (Ovid), and Cochrane Central (Wiley) up to December 2020. Additionally, we identified randomized controlled trials from the systematic reviews. We included randomized controlled trials comparing surgery with the selected nonsurgical treatments in individuals aged 18 years or older, regardless of other comorbidities or severity of carpal tunnel syndrome. Our primary outcomes were symptom severity including paraesthesia and pain, functional impairment, and health-related quality of life. Secondary outcomes included adverse events. Data from 6 months, 1 year, 2 years and 5 years were retrieved, and primary time point of interest was set at 1 year. Two researchers independently selected trials for inclusion and assessed risk of bias of the included randomized controlled trials according to the Cochrane Handbook for Systematic Reviews of Interventions (ROB1). One researcher extracted data, and one checked the accuracy of the data. We calculated measures of effect as mean difference (MD) or standardized mean difference (SMD) with 95% confidence interval (CI) for continuous outcomes, and risk ratio (RR) with 95% CI for dichotomous outcomes. We merged data into meta-analyses when possible, and we present data as forest plots if appropriate. We assessed certainty of evidence for the primary outcomes at 1 year with Grading of Recommendations Assessment, Development and Evaluation (GRADE). Due to great uncertainty in the estimates of the relative efficacy, we conducted a simplified assessment of economic consequences in the form of a cost analysis where the costs of the relevant non-surgical treatment alternatives in Norway, i.e., steroid injection and splinting, were estimated and compared to the costs of surgery for patients with mild to moderate carpal tunnel syndrome. In addition, we conducted a simple budget impact analysis to show possible cost savings.

Project Status: Completed

URL for project: https://www.fhi.no/en/cristin-projects/ongoing/surgery-for-carpal-tunnel-syndrome---protocol-for-health-technology-assessm/

Year Published: 2021

URL for published report: https://www.fhi.no/en/publ/2021/Surgical-Treatment-of-Carpal-Tunnel-Syndrome/

English language abstract: An English language summary is available

Publication Type: Full HTA

Country: Norway

Organisation Name: Norwegian Institute of Public Health

Contact Address: P.O. Box 222 Skoyen, N-0123, Oslo