The relative effectiveness of supervised exercise with and without spinal manipulation, and home exercise in terms of fear-avoidance beliefs in chronic neck pain patients.

Abstract

Neck pain and related disability place considerable burden on individuals and societies around the globe. Chronic neck pain is considered to be multifactorial in both mechanism and experience, including biological, psychological, and social factors. Little is known regarding the relationship of fear-avoidance beliefs, a specific psychological factor, to chronic neck pain. The primary objective here is to address the relative effectiveness of supervised exercise with and without spinal manipulation, versus home exercise in terms of fear-avoidance beliefs in chronic neck pain patients over time. This was a randomized, mixed-methods, comparative effectiveness trial conducted at an outpatient university-affiliated research clinic in the Minneapolis/St. Paul metropolitan area. Adults aged 18-65 with chronic, mechanical, non-specific neck pain rated at least 3 on 0-10 scale were included. Qualifying participants were individually randomized to receive one of three 12-week interventions: a) supervised rehabilitative exercise (SRE), b) SRE and spinal manipulative therapy (SMT), or c) home exercise with advice (HEA). The randomization scheme had a 1:1:1 allocation ratio using randomly permuted block sizes; treatment assignment was concealed in sequentially numbered, opaque, sealed envelopes. The self-report Fear-Avoidance Beliefs Questionnaire (FABQ) modified for neck was administered at baseline (week 0) and 4, 12, 26, and 52 weeks post-randomization. The two subscores, work (W) and physical activity (PA), were converted to a 0-100 point scale to facilitate comparison. The outcomes were analyzed with a linear mixed-effects model for repeated measures over time with baseline values treated as outcome. A total of 270 subjects were randomized into the trial. Loss-to-follow up rates at week 12 ranged from 5.6% to 7.7% for FABQ-PA and 8.0% to 10.9% for FABQ-W; these increased through week 52 to 16.7% to 18.7% for FABQ-PA and 21.3% to 29.7% for FABQ-W. At baseline, participants reported neck pain of nine to ten years in duration that was moderate in severity; they reported mild disability. Scores for FABQ-PA were 45.8 to 48.5 and FABQ-W scores were 22.0 to 25.4 on a 0-100 scale. For FABQ-W at 12 weeks, there was a statistically significant between-group difference (baseline to week 12) in favor of the SRE + SMT group when compared to the SRE group (5.30 points; 95% CI, 0.99 to 9.62; p=0.016); this difference lost significance at weeks 26 and 52. For FABQ-PA at 12 weeks, there were no statistically significant group differences (baseline to week 12); differences remained small and not statistically significant through week 52. Except for marginal improvements in fear-avoidance beliefs about work in favor of SRE+SMT in the short term (12 weeks), no other statistically significant between-group differences were observed for work and physical activity fear avoidance beliefs. These results should be interpreted cautiously due to limitations of the Fear-Avoidance Beliefs Questionnaire and the Fear-Avoidance Model of Exaggerated Pain Perception. Future research can address shortcomings of the FAM model and the FABQ instrument.