CONTEXT: Little is known about recovery after spinal manipulation in patients with low back pain (LBP). OBJECTIVE: To assess recovery from chronic LBP after a short regimen of osteopathic manipulative treatment (OMT) in a responder analysis of the OSTEOPAThic Health outcomes In Chronic low back pain (OSTEOPATHIC) Trial. METHODS: A randomized double-blind, sham-controlled trial was conducted to determine the efficacy of 6 OMT sessions over 8 weeks. Recovery was assessed at week 12 using a composite measure of pain recovery (10 mm or less on a 100-mm visual analog scale) and functional recovery (2 or less on the Roland-Morris Disability Questionnaire for back-specific functioning). The RRs and numbers-needed-to-treat (NNTs) for recovery with OMT were measured, and corresponding cumulative distribution functions were plotted according to baseline LBP intensity and back-specific functioning. Multiple logistic regression was used to compute the OR for recovery with OMT while simultaneously controlling for potential confounders. Sensitivity analyses were performed to corroborate the primary results. RESULTS: There were 345 patients who met neither of the recovery criteria at baseline in the primary analyses and 433 patients who met neither or only 1 of these criteria in the sensitivity analyses. There was a large treatment effect for recovery with OMT (RR, 2.36; 95% CI, 1.31-4.24; P=.003), which was associated with a clinically relevant NNT (8.9; 95% CI, 5.4-25.5). This significant finding persisted after adjustment for potential confounders (OR, 2.92; 95% CI, 1.43-5.97; P=.003). There was also a significant interaction effect between OMT and comorbid depression (P=.02), indicating that patients without depression were more likely to recover from chronic LBP with OMT (RR, 3.21; 95% CI, 1.59-6.50; P<.001) (NNT, 6.5; 95% CI, 4.2-14.5). The cumulative distribution functions demonstrated optimal RR and NNT responses in patients with moderate to severe levels of LBP intensity and back-specific dysfunction at baseline. Similar results were observed in the sensitivity analyses. CONCLUSIONS: The OMT regimen was associated with significant and clinically relevant measures for recovery from chronic LBP. A trial of OMT may be useful before progressing to other more costly or invasive interventions in the medical management of patients with chronic LBP. (ClinicalTrials.gov number NCT00315120).