Study design: Case study.Objective: To demonstrate the importance of assessment and treatment of the thoracic spine in the management of a patient with signs and symptoms of upper extremity Complex Regional Pain Syndrome Type I (CRPS-I).Background: The patient was a 38-year-old woman who suffered a traumatic injury to her left hand. Five months after injury, she presented with severe pain, immobility of the left arm, and associated dystrophic changes. She was unable to work and needed help in some activities of daily living.Methods and measures: The patient was treated for 3 months in 36 visits. Initial treatment consisted of cutaneous desensitization, edema management, and gentle therapeutic exercises. However, further examination indicated hypomobility and hypersensitivity of the upper thoracic spine. Joint manipulation of the T3 and T4 segments was implemented. The patient's status was monitored and range of motion, strength, temperature, and skin moisture were measured.Results: Immediately after the vertebral manipulation, there was a significant increase in the left hand's skin temperature and a decrease in hyperhydrosis as measured by palpation. Shoulder range of motion increased from 135-175 degrees and the patient reported reduced pain from 6/10 to 3/10 on a scale from 0 to 10, where 0 represents no pain. The decrease in the patient's dystrophic and allodynic symptoms permitted further progress in functional re-education. The patient was discharged with full return to independence and initiation of a vocational retraining program.Conclusion: Assessment and treatment of the thoracic spine should be considered in patients with upper extremity CRPS-I.