gms | German Medical Science

Objective: The dorsal root ganglion is a promising new target in neuromodulation of chronic pain states of different origin. Commonly used in the lumbar region, DRG can be used in the upper thoracic and cervical region with slight alterations of the surgical approach. Data on outcome and complications rates of DRG in this region are limited.

Method: We report on a consecutive series of 11 patients treated with DRG stimulation (Spinal Modulation^®) in the upper thoracic and cervical region. All patients suffered from chronic pain due to peripheral nerve or brachial plexus injuries, spinal cord surgery, post-herpetic neuralgia or CRPS II. All patients had trials with externalized electrodes for 3-7 days; a successful trial was defined as at least 50% pain reduction.

Results: Out of all 11 patients trials, 9 were successfull and implanted with a permanent stimulation system. Two patients had one electrode implanted, all other were implanted with two electrodes in adjacent segments. Of the finally implanted patients, all but one patient (suffering from post-herpetic neuralgia) reported permanent clinical significant pain reduction (VAS reduction from mean 8.1 to 2.3). Loss of treatment effect requiring reprogramming was commonly observed during the first few months of treatment. In one patient a transient paresis of the arm and hand was observed immediately following electrode implantation.

Conclusions: Cervical and upper thoracic DRG stimulation is feasible and resulted in good overall response rates to trials and excellent long-term pain relief in primary responders. A modified approach has to be used when compared with lumbar DRG electrode placement. Surgery itself in this region is more prone to complications and more challenging. Best results were seen in patients with injuries to the brachial plexus and peripheral nerve.