Bowstringing as a complication of deep brain stimulation

Deep brain stimulation (DBS) is an established surgical therapy for intractable movement disorders, such as Parkinson's disease, essential tremor and dystonia. As the number of treated patients has increased rapidly, new sets of problems about complications of DBS have arisen. Bowstringing is defined as abnormal tethering of leads between the pulse generators and stimulating electrode, associated with pain and contracture of the neck over the extension cable. We report the case of a 56-year-old woman with a history of advanced Parkinson's disease who had been treated by implantation of a bilateral, subthalamic nucleus, deep brain stimulator. A car accident caused the rupture of the right electrode, which was replaced. Six months after the replacement the patient presented disabling pain and tension in the neck where deep brain extension cables were located. A cervical incision was performed to excise scar tissue. Bowstringing is a rare complication of DBS and although patients sometimes report discomfort and tension in the cervical region, surgical procedures are not normally required.