PT  - JOURNAL ARTICLE
AU  - Ingemanson, Morgan L.
AU  - Rowe, Justin R.
AU  - Chan, Vicky
AU  - Wolbrecht, Eric T.
AU  - Reinkensmeyer, David J.
AU  - Cramer, Steven C.
TI  - Somatosensory system integrity explains differences in treatment response after stroke
AID  - 10.1212/WNL.0000000000007041
DP  - 2019 Mar 05
TA  - Neurology
PG  - e1098--e1108
VI  - 92
IP  - 10
4099  - http://n.neurology.org/content/92/10/e1098.short
4100  - http://n.neurology.org/content/92/10/e1098.full
SO  - Neurology2019 Mar 05; 92
AB  - Objective To test the hypothesis that, in the context of robotic therapy designed to enhance proprioceptive feedback via a Hebbian model, integrity of both somatosensory and motor systems would be important in understanding interparticipant differences in treatment-related motor gains.Methods In 30 patients with chronic stroke, behavioral performance, neural injury, and neural function were quantified for somatosensory and motor systems. Patients then received a 3-week robot-based therapy targeting finger movements with enhanced proprioceptive feedback.Results Hand function improved after treatment (Box and Blocks score increase of 2.8 blocks, p = 0.001) but with substantial variability: 9 patients showed improvement exceeding the minimal clinically important difference (6 blocks), while 8 patients (all of whom had >2-SD greater proprioception deficit compared to 25 healthy controls) showed no improvement. In terms of baseline behavioral assessments, a somatosensory measure (finger proprioception assessed robotically) best predicted treatment gains, outperforming all measures of motor behavior. When the neural basis underlying variability in treatment response was examined, somatosensory-related variables were again the strongest predictors. A multivariate model combining total sensory system injury and sensorimotor cortical connectivity (between ipsilesional primary motor and secondary somatosensory cortices) explained 56% of variance in treatment-induced hand functional gains (p = 0.002).Conclusions Measures related to the somatosensory network best explained interparticipant differences in treatment-related hand function gains. These results underscore the importance of baseline somatosensory integrity for improving hand function after stroke and provide insights useful for individualizing rehabilitation therapy.ClinicalTrials.gov identifier: NCT02048826.B&B=Box and Blocks; CST=corticospinal tract; FINGER=Finger Individuating Grasp Exercise Robot; MNI=Montreal Neurological Institute; ROI=region of interest; TST=thalamocortical spinal tract