caa a22 4500 445353147 CHVBK 20180317142851.0 cr unu---uuuuu 170323e20110401xx s 000 0 eng 10.1007/s00221-011-2594-2 doi (NATIONALLICENCE)springer-10.1007/s00221-011-2594-2 Differentiation between the contributions of shortening reaction and stretch-induced inhibition to rigidity in Parkinson's disease [Elektronische Daten] [Ruiping Xia, Douglas Powell, W. Rymer, Nicholas Hanson, Xiang Fang, A. Threlkeld] Parkinsonian rigidity is characterized by an increased resistance of a joint to externally imposed motion that remains uniform with changing joint angle. Two candidate mechanisms are proposed for the uniformity of rigidity, involving neural-mediated excitation of shortening muscles, i.e., shortening reaction (SR), or inhibition of stretched muscles, i.e., stretch-induced inhibition (SII). To date, no study has addressed the roles of these two phenomena in rigidity. The purpose of this study was to differentiate these two phenomena, and to quantify the potential contribution of each to wrist joint moment in 17 patients with parkinsonian rigidity, in both Off- and On-medication states. Joint position, torque, and EMGs of selected muscles were collected during externally imposed flexion and extension motions. Moments of shortened and stretched muscles were estimated using a biomechanical model. Slopes of the estimated torque-angle curve were calculated for shortened and stretched muscles, separately. A mixed model ANOVA was performed to compare the contribution between the two mechanisms. During flexion, slopes were significantly (P=0.003) smaller for SR than for SII, whereas during extension, slopes for SII were significantly (P=0.003) smaller. Results showed that both SR and SII contributed to rigidity. Which mechanism predominates appeared to be associated with the direction of movement. The findings provide new insights into the biomechanical underpinnings of this common symptom in Parkinson's disease. Springer-Verlag, 2011 Rigidity nationallicence Biomechanical modeling nationallicence Shortening reaction nationallicence Stretch-induced inhibition nationallicence Parkinson's disease nationallicence Xia Ruiping Rehabilitation Science Research Laboratory, Department of Physical Therapy, Creighton University, 2500 California Plaza, 68178, Omaha, NE, USA aut Powell Douglas Rehabilitation Science Research Laboratory, Department of Physical Therapy, Creighton University, 2500 California Plaza, 68178, Omaha, NE, USA aut Rymer W. Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, IL, USA aut Hanson Nicholas Rehabilitation Science Research Laboratory, Department of Physical Therapy, Creighton University, 2500 California Plaza, 68178, Omaha, NE, USA aut Fang Xiang Division of Biostatistics, Office of Research and Compliance, Creighton University, Omaha, NE, USA aut Threlkeld A. Rehabilitation Science Research Laboratory, Department of Physical Therapy, Creighton University, 2500 California Plaza, 68178, Omaha, NE, USA aut Experimental Brain Research Springer-Verlag 209/4(2011-04-01), 609-618 0014-4819 209:4<609 2011 209 221 https://doi.org/10.1007/s00221-011-2594-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00221-011-2594-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Xia Ruiping Rehabilitation Science Research Laboratory, Department of Physical Therapy, Creighton University, 2500 California Plaza, 68178, Omaha, NE, USA aut NATIONALLICENCE 700 1- Powell Douglas Rehabilitation Science Research Laboratory, Department of Physical Therapy, Creighton University, 2500 California Plaza, 68178, Omaha, NE, USA aut NATIONALLICENCE 700 1- Rymer W. Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, IL, USA aut NATIONALLICENCE 700 1- Hanson Nicholas Rehabilitation Science Research Laboratory, Department of Physical Therapy, Creighton University, 2500 California Plaza, 68178, Omaha, NE, USA aut NATIONALLICENCE 700 1- Fang Xiang Division of Biostatistics, Office of Research and Compliance, Creighton University, Omaha, NE, USA aut NATIONALLICENCE 700 1- Threlkeld A. Rehabilitation Science Research Laboratory, Department of Physical Therapy, Creighton University, 2500 California Plaza, 68178, Omaha, NE, USA aut NATIONALLICENCE 773 0- Experimental Brain Research Springer-Verlag 209/4(2011-04-01), 609-618 0014-4819 209:4<609 2011 209 221 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer