title: Dual Anchor Internal Pulse Generator Technique May Lower Risk of Twiddler's Syndrome: A Case Series and Literature Review.
abstract: BACKGROUND
  Twiddler's syndrome (TS) is described as a spontaneous rotation or intentional external manipulation of implanted internal pulse generator (IPG) for neurological or cardiac disorders. There have been identified some predisposing factors of the development of TS such as: loose subcutaneous tissue, older age of individuals undergoing deep brain stimulation (DBS) procedures, creation of too large pockets for IPG. Apart from these factors, the construction of IPG itself may predispose to the development of TS.
  
  
  OBJECTIVE
  To report the clinical course of three patients with TS. Moreover, the purpose of this study is to present the change in fixation technique of IPG that can prevent the occurrence of TS in patients after DBS procedure.
  
  
  METHODS
  A prospectively collected database of all hardware related complications for patients operated on for various movement disorders was analyzed. In a total number of 347 DBS systems implanted since 1999 we have identified three patients diagnosed with TS. All three patients with TS in our series were implanted with the IPG harboring a single anchoring hole. This complication has never occurred in patients with the IPG harboring two anchoring holes in our center.
  
  
  RESULTS
  All three patients underwent revision surgery. During reoperations all connection cables were replaced and IPG sutured with one additional silk stich through the plastic housing to immobilize it properly in subcutaneous pocket. There were no recurrences of TS in our patients.
  
  
  CONCLUSIONS
  Our case series suggests that a predisposing factor of TS may also be the construction of IPG itself (a single anchoring hole intended for fixation), which naturally represents less fixation of the IPG to the fascia or muscle in the subcutaneous pocket. In this preliminary report we present suggestions to lower the risk of TS, including using dual anchor capable IPGs, reducing pocket volume and using nonabsorbable suture.
authors.affiliation: Neurosurgical Department of Postgraduate Medical Center, Kondratowicza, Warsaw, Poland.
authors.forename: Michał Roman
authors.initials: MR
authors.lastname: Sobstyl
authors.affiliation: Neurosurgical Department of Postgraduate Medical Center, Kondratowicza, Warsaw, Poland.
authors.forename: Mirosław
authors.initials: M
authors.lastname: Ząbek
authors.affiliation: Faculty of Rehabilitation, Józef Piłsudski University of Physical Education, Warsaw, Poland.
authors.forename: Grażyna
authors.initials: G
authors.lastname: Brzuszkiewicz-Kuźmicka
authors.affiliation: Neurosurgical Department of Postgraduate Medical Center, Kondratowicza, Warsaw, Poland.
authors.forename: Tomasz
authors.initials: T
authors.lastname: Pasterski
mesh_terms: D000368:Aged; D046690:Deep Brain Stimulation / Q000009:adverse effects* / Q000295:instrumentation* / Q000379:methods; D004567:Electrodes, Implanted / Q000009:adverse effects*; D004868:Equipment Failure; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000175:diagnosis / Q000628:therapy; D011183:Postoperative Complications / Q000175:diagnosis* / Q000209:etiology*; D011446:Prospective Studies
keywords: Deep brain stimulation; Parkinson's disease; Twiddler's syndrome; dyskinesia; hardware failure; tremor