Introduction: Complex regional pain syndrome type I (CRPS I) is a chronic condition with disturbances in the sympathetic, somatosensory and motor nervous systems. Objective: To assess the efficacy of combined thoracic manipulation (TM) and traditional physical therapy treatment (TPT) versus TPT treatment alone on pain severity at rest and functional disability in CRPS I patients after upper-limb trauma. Methods: Thirty participants with CRPS I were divided into 2 groups equally at random. The control group (A) consisted of 15 patients with a median (interquartile range [IQR]) age of 53 (13) years. This group received TPT, which consisted of transcutaneous electrical neuromuscular stimulation, mirror therapy, and exercises. The experimental group (B) consisted of 15 patients with a median (IQR) age of 50 (12) years. This group received TPT and TM. The treatment was provided 3 days a week for 12 weeks. Before and after treatment, patients were assessed for pain severity using a visual analogue scale and functional disability using the questionnaire of Disability of Arm, Shoulder, and Hand. Results: As compared with before treatment, all patients showed significant improvement in all measured variables after treatment. Even so, there was a nonsignificant difference in pain severity at rest (p=0.09) , but favoured in group B. In terms of functional disability, there was a significant difference between the groups (p__ampersandsignlt;0.001) favoured in group B posttreatment. Conclusion: TPT combined with TM is more effective for treating CRPS I after upper-extremity trauma.