Provider adherence with clinical practice guidelines (CPGs) for acute low back pain (LBP) and its impact on clinical outcomes and cost are controversial. A panel and cross-sectional design was used to determine the rate of provider adherence to the Department of Defense/Veteran's Administration CPG for Acute LBP which included ergonomic and psychosocial intervention. The relationship among adherent care, patient satisfaction, general health, functional outcome, and cost was examined. Direct health services and patient survey data 1 year before and 3 years following guideline implementation were analyzed. The sample consisted of 15,789 LBP cases (CPG) and 14,409 upper extremity cases used as controls (no CPG). Ten to 40% of LBP cases received CPG-adherent care across the 4 years. No differences were found between LBP and upper extremity diagnoses groups in the rates of change in the four outcomes over years. Multivariable regression analyses controlling for demographic variables and perceived health indicated that CPG adherence was related to better functional outcomes, Odds ratio (OR)=1.45 [95% CI=1.31-1.60] and lower healthcare costs (beta=-230.15, p<0.001). Cases receiving more adherent care also reported higher levels of patient satisfaction (beta=0.09, p<0.05) and general health, OR=1.44 [95% CI=1.29-1.60]. Higher levels of adherent care which included efforts to address both ergonomic and psychosocial factors in the course of acute back pain were related to better clinical outcomes and lower costs.