Traction Therapy for Cervical Radicular Syndrome is Statistically Significant but not Clinically Relevant for Pain Relief. A Systematic Literature Review with Meta-Analysis and Trial Sequential Analysis

Aim: We aimed to investigate the effectiveness of traction therapy in reducing pain by performing a systematic review with meta-analysis. We also explore the best modality for administering traction to patients with cervical radicular syndrome (CRS). Methods: We searched the Medline, Physiotherapy Evidence Database (PEDro), Cochrane Central Register of Controlled Trials, and Cumulative Index to Nursing and Allied Health Literature (CINAHL) electronic databases. Two reviewers independently selected randomized controlled trials (RCTs) that compared traction in addition to other treatments versus the effectiveness of other treatments alone for pain outcome. We calculated the mean differences (MDs) and 95% confidence intervals (CIs). We used Cochrane's tool to assess risk of bias and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to evaluate the quality of evidence and summarize the study conclusions. Results: A total of seven studies (589 patients), one with low risk of bias, were evaluated. An overall estimate of treatment modalities showed low evidence that adding traction to other treatments is statistically significant (MD -5.93 [95% CI, -11.81 to -0.04] P = 0.05 and I-2 = 57%) compared to other treatments alone. The subgroup analyses were still statistically significant only for mechanical and continuous modalities. Conclusions: Overall analysis showed that, compared to controls, reduction in pain intensity after traction therapy was achieved in patients with cervical radiculopathy. However, the quality of evidence was generally low and none of these effects were clinically meaningful.