Pain pattern classification and directional preference for patients with neck pain

Objectives: Pain Pattern Classification (PPC) and Directional Preference (DP) have been shown to be predictive of health care outcomes and serve to guide orthopedic clinical decision making. We conducted a prospective, observational cohort study to verify the association between PPC, DP, and clinical outcomes. Methods: Clinical outcome measures including pain intensity and disability were completed at first examination and follow-up by 335 patients. A Pearson's chi-squared test was used to determine differences in prevalence rates for the categorical variables, and two-sample t-tests were used to determine differences in rates for the continuous variables. A Tukey's range test was used to determine differences in follow-up pain intensity and disability for neck pain dual-classification schemes. Results: The prevalence of DP was 82.4%. The prevalence of CEN, Non-CEN, and Non-Classifiable (NC) was 15.2%, 42.1%, and 25.1%, respectively. The prevalence of DP was lowest for patients with sub-acute symptoms and who were <45 years old. Patients classified as DP CEN had, on average 2.62 NDI units less than patients classified as Non-DP. Patients classified as DP CEN had, on average, 0.90 pain intensity units less than patients classified as Non-DP at follow-up. Patients who demonstrated DP CEN did not have clinically significant lower pain intensity or disability at follow-up than patients who demonstrated Non-DP. Discussion: The results of this investigation need to be interpreted with caution with respect to the study design and it's subsequent strengths and limitations. Level of Evidence: 1b.