Disease-specific longevity of impulse generators in deep brain stimulation and review of the literature.

Deep brain stimulation (DBS) represents an established and internationally approved therapy for movement disorders. In the present retrospective analysis, we evaluated disease-specific longevity of dual channel impulse generators (IPG) used in different movement disorders. We correlated the battery lifetime with electrical stimulation settings, "total electrical energy delivered" (TEED), stimulation modi (monopolar, double monopolar and bipolar) and targets. Specifically, we reviewed the longevity and stimulation settings of 464 IPGs implanted between 1996 until 2011 in a single university center. Disease entities comprised Parkinson's disease (PD, n = 257), dystonia (n = 130) and essential tremor (ET, n = 50). Further subanalyses aimed at assessing differential longevity in different subtypes of PD and dystonia. The main finding relates to longer IPG longevity in ET (thalamic DBS) and PD (subthalamic DBS) vs. dystonia (pallidal DBS; 71.9 ± 6.7 vs. 51.5 ± 2.3 vs. 37 ± 2 months). In PD the tremor-dominant type was associated with a significant shorter battery survival than in the akinetic-rigid type without tremor or the "balanced" type with tremor, bradykinesia and rigidity (38.8 ± 3.9 vs. 53.6 ± 3.4 vs. 58.8 ± 4.1 months), while there were no significant differences in longevity between the subtypes of dystonia. Frequency, amplitude, pulse widths and TEED correlated inversely with battery lifetime. Pallidal DBS in dystonia is associated with a shorter lifetime of IPGs than subthalamic or thalamic DBS for PD or ET. The present results may contribute to the rapidly evolving refinement of DBS devices. Future studies that assess energy consumption both in patients with and without IPG replacement could help to avoid potential underestimation of longevity of IPGs.

Combined open bipolar Monteggia and Galeazzi fracture: a case report with a 1-year follow-up.

Monteggia and Galeazzi fractures account for 1-5% of total forearm fractures. A combined Monteggia and Galeazzi fracture is an extremely rare injury. We present a case of a Gustillo-Henderson type 2 open combined bipolar Monteggia and Galeazzi fracture, as well as fracture of the ulnar coronoid process in a 49-year old male. The patient was treated surgically, with open reduction and internal fixation. At 6 months postoperative, he was diagnosed with pseudarthrosis and underwent surgery with autologous bone grafting from the iliac crest. At the 1-year follow-up, the patient presented an extension deficit of 5° in elbow, a 15° deficit in pronation and 20° deficit in supination of the wrist. The patient continues to work as a painter without significant problems in his everyday routine and he is still regularly engaged in cycling. Additionally we provide a historical background of these injuries.