Association between centralization and directional preference and functional and pain outcomes in patients with neck pain.

STUDY DESIGN Retrospective cohort. OBJECTIVES In subjects with neck pain, the present study aimed (1) to describe the prevalence of centralization (CEN), noncentralization (non-CEN), directional preference (DP), and no directional preference (no DP); (2) to determine if age, sex, fear-avoidance beliefs about physical activity, number of comorbid conditions, or symptom duration varies among subjects who demonstrate CEN versus non-CEN and DP versus no DP; and (3) to determine if CEN and/or DP are associated with changes in function and pain. BACKGROUND CEN and DP are prevalent among patients with low back pain and should be considered when determining treatment strategies and predicting outcomes; however, these findings are not well investigated in patients with neck pain. METHODS Three hundred four subjects contributed data. CEN and DP prevalence were calculated, as was the association between CEN and DP, and age, sex, number of comorbid conditions, fear-avoidance beliefs, and symptom duration. Multivariate models assessed whether CEN and DP predicted change in function and pain. RESULTS CEN and DP prevalence were 0.4 and 0.7, respectively. Younger subjects and those with fewer comorbid conditions were more likely to centralize; however, subjects who demonstrated DP were more likely to have acute symptoms. Subjects who centralized experienced, on average, a 3.6-point (95% confidence interval: -0.3, 7.4) improvement in function scores, whereas subjects with a DP averaged a 5.4-point (95% confidence interval: 0.8, 10.0) improvement. Neither CEN nor DP was associated with pain outcomes. CONCLUSION DP and, to a lesser extent, CEN represent evaluation categories that are associated with improvements in functional outcomes.