| Autor: |
Park H; School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA,USA.; Department of Electrical & Computer Engineering, Texas A&M University, College Station, TX,USA.; Department of Biomedical Engineering, Sungkyunkwan University, Suwon,South Korea., Klishko AN; School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA,USA., Oh K; School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA,USA.; Department of Neuroscience and Kennedy Krieger Institute, The Johns Hopkins University School of Medicine, Baltimore, MD,USA., Zhang C; School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA,USA., Grenga G; School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA,USA., Herrin KR; George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA,USA., Dalton JF; Georgia Hand, Shoulder & Elbow, Atlanta, GA,USA., Kistenberg RS; School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA,USA., Lemay MA; Temple University, Philadelphia, PA,USA., Pitkin M; Tufts University School of Medicine, Boston, MA,USA.; Poly-Orth International, Sharon, MA,USA., DeWeerth SP; School of Electrical and Computer Engineering and Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA,USA.; Departments of Bioengineering and of Electrical and Computer Engineering, Lehigh University, Bethlehem, PA,USA., Prilutsky BI; School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA,USA. |
| Abstrakt: |
Cutaneous feedback from feet is involved in regulation of muscle activity during locomotion, and the lack of this feedback results in motor deficits. We tested the hypothesis that locomotor changes caused by local unilateral anesthesia of paw pads in the cat could be reduced/reversed by electrical stimulation of cutaneous and proprioceptive afferents in the distal tibial nerve during stance. Several split-belt conditions were investigated in four adult female cats. In addition, we investigated the effects of similar distal tibial nerve stimulation on overground walking of one male cat that had a transtibial, bone-anchored prosthesis for 29 months and, thus, had no cutaneous/proprioceptive feedback from the foot. In all treadmill conditions, cats walked with intact cutaneous feedback (control), with right fore- and hindpaw pads anesthetized by lidocaine injections, and with a combination of anesthesia and electrical stimulation of the ipsilateral distal tibial nerve during the stance phase at 1.2× threshold of afferent activation. Electrical stimulation of the distal tibial nerve during the stance phase of walking with anesthetized ipsilateral paw pads reversed or significantly reduced the effects of paw pad anesthesia on several kinematic variables, including lateral center of mass shift, cycle and swing durations, and duty factor. We also found that stimulation of the residual distal tibial nerve in the prosthetic hindlimb often had different effects on kinematics compared with stimulation of the intact hindlimb with paw anesthetized. We suggest that stimulation of cutaneous and proprioceptive afferents in the distal tibial nerve provides functionally meaningful motion-dependent sensory feedback, and stimulation responses depend on limb conditions. |
