Predictors for positive response to home kinematic training in chronic neck pain

Objectives: There is strong evidence for exercise therapy in neck pain, but a wide variety of protocols. Predictors for outcome are unknown and current practice is based on trial and error. The objective of this study was to identify predictors for response to home kinematic training (KT) considering improvement in both self-reported and kinematic measures. Methods: A continuing analysis of data from the second phase of a randomized controlled trial, which included 4 weeks of KT using laser or virtual reality, with baseline, postintervention, and 3-month follow-up measures. Positive self-reported response was defined as a ≥50% pain reduction, ≥7% reduction in neck disability index (NDI), or a global perceived effect of 3 to 5 of 5. A second model defined improvement by ≥40% increase in cervical velocity. Results: Data were retrieved from 79 participants with chronic neck pain who completed the postintervention evaluation and 52 who completed the 3-month follow-up. Self-reported response was 71% to 73% and kinematic response was 41% to 46%. Prediction models indicated an immediate increase in self-reported measures in men with NDI ≥ 20% slower (≤65°/s), and less accurate (≥16° error) cervical motion at baseline. In the longer term, older patients with higher NDI seemed to benefit more. In the second model, no factors significantly predicted improvement in kinematic measures at either time point. Conclusion: A high positive response rate to home KT was found by self-reported criteria. Males with poorer clinical and kinematic presentation at baseline, that is greater disability and slower neck motion, were more likely to respond