title: Exploratory study on the effects of a robotic hand rehabilitation device on changes in grip strength and brain activity after stroke.
abstract: BACKGROUND
  The brain mechanisms underlying successful recovery of hand fuenction after stroke are still not fully understood, although functional MRI (fMRI) studies underline the importance of neuronal plasticity.
  
  
  METHODS
  We explored potential changes in brain activity in 7 patients with subacute to chronic stroke (69 ± 8 years) with moderate- to high-grade distal paresis of the upper limb (Motricity Index: 59.4) after standardized robotic finger-hand rehabilitation training, in addition to conventional rehabilitation therapy for 3 weeks. Behavioral and fMRI assessments were carried out before and after training to characterize changes in brain activity and behavior.
  
  
  RESULTS
  The Motricity Index (pre: 59.4, post: 67.2, P < .05) and grip force (pre: 7.26, post: 11.87, P < .05) of the paretic hand increased significantly after rehabilitation. On fMRI, active movement of the affected (left) hand resulted in contralesional (ie, ipsilateral) activation of the primary sensorimotor cortex prior to rehabilitation. After rehabilitation, activation appeared "normalized," including the ipsilesional primary sensorimotor cortex and supplementary motor area (SMA). No changes and no abnormalities of activation maps were seen during movement of the unaffected hand. Subsequent region-of-interest analyses showed no significant ipsilesional activation increases after rehabilitation.
  
  
  CONCLUSIONS
  Despite behavioral improvements, we failed to identify consistent patterns of functional reorganization in our sample. This warrants caution in the use of fMRI as a tool to explore neural plasticity in heterogeneous samples lacking sufficient statistical power.
authors.affiliation: Department of Neurology, Medical University of Graz, Graz, Austria.
authors.forename: Daniela
authors.initials: D
authors.lastname: Pinter
authors.forename: Sandra
authors.initials: S
authors.lastname: Pegritz
authors.forename: Christa
authors.initials: C
authors.lastname: Pargfrieder
authors.forename: Gudrun
authors.initials: G
authors.lastname: Reiter
authors.forename: Walter
authors.initials: W
authors.lastname: Wurm
authors.forename: Thomas
authors.initials: T
authors.lastname: Gattringer
authors.forename: Regina
authors.initials: R
authors.lastname: Linderl-Madrutter
authors.forename: Claudia
authors.initials: C
authors.lastname: Neuper
authors.forename: Franz
authors.initials: F
authors.lastname: Fazekas
authors.forename: Peter
authors.initials: P
authors.lastname: Grieshofer
authors.forename: Christian
authors.initials: C
authors.lastname: Enzinger
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000473:pathology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006225:Hand / Q000503:physiopathology*; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D010100:Oxygen / Q000097:blood; D011597:Psychomotor Performance; D012371:Robotics / Q000295:instrumentation* / Q000379:methods*; D013003:Somatosensory Cortex / Q000098:blood supply / Q000503:physiopathology*; D020521:Stroke / Q000473:pathology / Q000503:physiopathology; D000071939:Stroke Rehabilitation
chemical_list: D010100:Oxygen