Also after bagatelle trauma, some patients can develop a complex regional pain syndrome (CRPS). The limb concerned usually shows a marked temperature difference to the contralateral side. Apart from a doughy swelling, the patient is impaired in particular by burning pain and a restricted range of motion. The objective of the present study was to examine the influence of early thoracic sympathetic nerve blockade on the basis of clinical and quantified blood flow parameters.In 7 young patients (average age 17.7 [15-21] years) with a clinically developing type 1 CRPS after sport injuries (mountain bike, bike, skateboard, hockey and go-kart accidents), occult injury and ligament lesions were ruled out using conventional imaging and MRI. In addition to pain-adapted physiotherapy and pharmacotherapy with analgesics and calcitonin, sympathetic nerve blockade was performed three times at two-day intervals. The CT-assisted puncture was performed in the prone position at the level of the intervertebral space of the 2nd/3rd thoracic vertebral bodies. In the correct paravertebral position, a 10-cm long, 22 G Seibel-Grönemeier needle was used for the successive injection of 6-10 ml Carbostesin 0.5 %. By adding a small amount of contrast medium, it was possible to visualise clearly the distribution of the sympathicolytic agent in the control scan in each case. Before and after the intervention, colour-coded duplex sonography (CCDS) of the affected limb arteries was performed on all patients.The injection needle was correctly placed in all patients, without complications. The medication mixture was observed to have distributed properly. After the intervention, all patients reported the immediate onset of marked pain relief, whereby they recovered fully over the further course. The increase in peripheral blood flow was shown by a significant improvement in flow in the CCDS.Outpatient CT-assisted temporary sympathetic nerve blockade is an effective and low-complication therapeutic option for the supportive treatment of patients with CRPS.