This study’s objective was to examine the effectiveness of cervical traction in addition to exercise for specific subgroups of patients with neck pain. Cervical traction is commonly used but its effectiveness has not been sufficiently examined. A critique of existing studies is a failure to target patients most likely to respond. Traction is ordinarily recommended for patients with cervical radiculopathy. A prediction rule has been described identifying a narrower subgroup of patients likely to respond. Patients with neck pain and signs of radiculopathy were randomized to 4 weeks of treatment with exercise, exercise with mechanical traction, or exercise with over-door traction. Baseline assessment included subgrouping rule status. Primary (Neck Disability Index (NDI) scored 0-100) and secondary outcomes (neck and arm pain intensity) were assessed after 4 weeks and 6 and 12 months. Primary analyses examined 2-way treatment by time interactions. Secondary analyses examined validity of the subgrouping rule by adding 3-way interactions. Eighty-six patients (53.5% female, mean age 46.9 years) were enrolled in the study. Intention-to-treat analysis found lower NDI scores in the mechanical traction group after 6 months compared to the exercise group (mean difference between groups = 13.3; 95% CI: 5.6, 21.0) or over-door traction group (mean difference between groups = 8.1; 95% CI: 0.8, 15.3); and compared to the exercise group after 12 months (mean difference between groups = 9.8; 95% CI: 0.2, 19.4). Secondary outcomes favored mechanical traction at several time points. Subgrouping rule validity was supported on the NDI at the 6 month time point only.
For the group studied. exercise augmented with manual traction for patients with cervical radiculopathy resulted in lower disability and pain, especially at long-term follow-ups.