This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.
Abstract
Objectives: Stimulation-induced hypokinetic gait disorders with freezing of gait (FOG) have been reported only recently as adverse effects of deep brain stimulation (DBS) of the globus pallidus internus (GPi) in patients with dystonia. The aim of this work was to determine the frequency and the nature of this GPi-DBS–induced phenomenon.
Methods: We retrospectively screened our database of patients with dystonia who underwent DBS. Patients with focal, segmental, or generalized dystonia of primary or tardive origin and no gait disorder due to lower limb dystonia before DBS, bilateral pallidal stimulation, and a follow-up for more than 6 months were included. Reports of adverse events were analyzed, and gait abnormalities were scored by comparing preoperative and postoperative video recordings using Movement Disorder Society–sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) items 3.10 (gait) and 3.11 (FOG). To assess the role of GPi-DBS in gait abnormalities, DBS was paused for 24 hours. Gait and FOG were assessed 30 minutes, 2 hours, and 24 hours after restarting DBS. Finally, a standardized adjustment algorithm was performed trying to eliminate the gait disorder.
Results: Of a collective of 71 patients with dystonia, 6 presented with a new gait disorder (8.5%; 2 men, 4 women, mean age 61.3 years [48–69 years], 2 craniocervical, 1 DYT-1 segmental, 1 truncal, 2 tardive dystonia). GPi-DBS improved Burke-Fahn-Marsden Dystonia Rating Scale motor score by 54% and disability score by 52%. MDS-UPDRS item 3.10 worsened from 0.5 (±0.8) to 2.0 (±0.9) and item 3.11 from 0 to 2.5 (±0.5). The gait disorder displayed shuffling steps and difficulties with gait initiation and turning. Increasing voltages improved dystonia but triggered FOG, sometimes worsening over a period of a few hours. It vanished within minutes after ceasing DBS. Electrode misplacement was ruled out. In all but one patient, no optimal configuration was found despite extensive testing of settings (monopolar, bipolar, pulse width 60–210 μs, frequency 60–180 Hz). Nevertheless, a compromise between optimal stimulation for dystonia and eliciting FOG was achieved in each case.
Conclusions: A hypokinetic gait disorder with FOG can be a complication of GPi-DBS.
GLOSSARY
- BFMDRS=
- Burke-Fahn-Marsden Dystonia Rating Scale;
- DBS=
- deep brain stimulation;
- FOG=
- freezing of gait;
- GPi=
- globus pallidus internus;
- MDS-UPDRS=
- Movement Disorder Society–sponsored revision of the Unified Parkinson's Disease Rating Scale;
- PD=
- Parkinson disease;
- TD=
- tardive dystonia
Footnotes
-
Supplemental data at www.neurology.org
- Received October 24, 2010.
- Accepted April 6, 2011.
- Copyright © 2011 by AAN Enterprises, Inc.
AAN Members
We have changed the login procedure to improve access between AAN.com and the Neurology journals. If you are experiencing issues, please log out of AAN.com and clear history and cookies. (For instructions by browser, please click the instruction pages below). After clearing, choose preferred Journal and select login for AAN Members. You will be redirected to a login page where you can log in with your AAN ID number and password. When you are returned to the Journal, your name should appear at the top right of the page.
AAN Non-Member Subscribers
Purchase access
Letters: Rapid online correspondence
REQUIREMENTS
You must ensure that your Disclosures have been updated within the previous six months. Please go to our Submission Site to add or update your Disclosure information.
Your co-authors must send a completed Publishing Agreement Form to Neurology Staff (not necessary for the lead/corresponding author as the form below will suffice) before you upload your comment.
If you are responding to a comment that was written about an article you originally authored:
You (and co-authors) do not need to fill out forms or check disclosures as author forms are still valid
and apply to letter.
Submission specifications:
- Submissions must be < 200 words with < 5 references. Reference 1 must be the article on which you are commenting.
- Submissions should not have more than 5 authors. (Exception: original author replies can include all original authors of the article)
- Submit only on articles published within 6 months of issue date.
- Do not be redundant. Read any comments already posted on the article prior to submission.
- Submitted comments are subject to editing and editor review prior to posting.
You May Also be Interested in
Topics Discussed
Alert Me
Recommended articles
Low-frequency stimulation of STN-DBS reduces aspiration and freezing of gait in patients with PD
Subthalamic nucleus deep brain stimulation in isolated dystonia
Subthalamic nucleus deep brain stimulation in primary cervical dystonia
Comparative effects of unilateral and bilateral subthalamic nucleus deep brain stimulation