Association between directional preference and centralization in patients with low back pain.

Abstract

Prospective, longitudinal, observational cohort. Primary aims were to determine (1) baseline prevalence of directional preference (DP) or no directional preference (no-DP) observed for patients with low back pain whose symptoms centralized (CEN), did not centralize (non-CEN), or could not be classified (NC), and (2) to determine if classifying patients at intake by DP or no-DP combined with CEN, non-CEN, or NC predicted functional status and pain intensity at discharge from rehabilitation. Although evidence suggests that patient response classification criteria DP or CEN improve outcomes, previous studies did not delineate relations between DP and CEN findings and outcomes. Eight therapists classified patients using standardized definitions for DP and CEN. Prevalence rates for DP and no-DP and CEN,non-CEN, and NC were calculated. Ordinary least-squares multivariate regression models assessed whether multilevel classification combining DP and CEN (DP/CEN, DP/non-CEN, DP/NC, no-DP/non-CEN, and no-DP/NC categories) predicted discharge functional status (scale range, 0 to 100, with higher values representing better function) or pain intensity (scale range, 0 to 10, with higher values representing more pain). Overall prevalence of DP and CEN was 60% and 41%, respectively. For those with DP, prevalence rates for DP/CEN, DP/non-CEN, and DP/NC were 65%, 27%, and 8%, respectively. The amount of variance explained (R2 values) for function and pain models was 0.50 and 0.39, respectively. Compared to patients classified as DP/CEN, patients classified as DP/non-CEN or no-DP/non-CEN reported 7.7 and 11.6 functional status units less at discharge (P<.001), respectively, and patients classified as no-DP/non-CEN reported 1.7 pain units more at discharge (P<.001). Findings suggest that classification by pain pattern and DP can improve a therapist's ability to provide a short-term prognosis for function and pain outcomes. Prognosis, level 1b-.