Signal features of surface electromyography in advanced Parkinson's disease during different settings of deep brain stimulation.
OBJECTIVE
Electromyography (EMG) and acceleration (ACC) measurements are potential methods for quantifying efficacy of deep brain stimulation (DBS) treatment in Parkinson's disease (PD). The treatment efficacy depends on the settings of DBS parameters (pulse amplitude, frequency and width). This study quantified, if EMG and ACC signal features differ between different DBS settings and if DBS effect is unequal between different muscles.


METHODS
EMGs were measured from biceps brachii (BB) and tibialis anterior (TA) muscles of 13 PD patients. ACCs were measured from wrists. Measurements were performed during seven different settings of DBS and analyzed using methods based on spectral analysis, signal morphology and nonlinear dynamics.


RESULTS
The results showed significant within-subject differences in the EMG signal kurtosis, correlation dimension, recurrence rate and EMG-ACC coherence between different DBS settings for BB but not for TA muscles. Correlations between EMG feature values and clinical rest tremor and rigidity scores were weak but significant.


CONCLUSIONS
Surface EMG features differed between different DBS settings and DBS effect was unequal between upper and lower limb muscles.


CONCLUSIONS
EMG changes pointed to previously defined optimal settings in most of patients, which should be quantified even more deeply in the upcoming studies.
Department of Applied Physics, University of Eastern Finland, Finland. Electronic address: saara.rissanen@uef.fi.
Saara M
SM
Rissanen
Department of Applied Physics, University of Eastern Finland, Finland.
Verneri
V
Ruonala
Department of Neurology, Helsinki University Central Hospital, Finland; BioMag Laboratory, Helsinki University Central Hospital, Finland.
Eero
E
Pekkonen
Department of Physical and Rehabilitation Medicine, Tampere University Hospital, Finland.
Markku
M
Kankaanpää
Department of Physical and Rehabilitation Medicine, Kuopio University Hospital, Finland.
Olavi
O
Airaksinen
Department of Applied Physics, University of Eastern Finland, Finland.
Pasi A
PA
Karjalainen
D000328:Adult; D000368:Aged; D046690:Deep Brain Stimulation / Q000379:methods*; D004576:Electromyography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy*; D016896:Treatment Outcome
Deep brain stimulation (DBS); Nonlinear dynamics; Parkinson’s disease (PD); Surface electromyography (EMG)