title: Communication between functional and denervated muscles using radiofrequency.
abstract: OBJECTIVE
  This article focuses on establishing communication between a functional muscle and a denervated muscle using a radiofrequency communications link. The ultimate objective of the project is to restore the eye blink in patients with facial nerve paralysis.
  
  
  METHODS
  Two sets of experiments were conducted using the gastrocnemius leg muscles of Sprague-Dawley rats. In the initial tests, varying magnitudes of voltages ranging from 0.85 to 2.5 V were applied directly to a denervated muscle to determine the voltage required to produce visible contraction. The second set of experiments was then conducted to determine the voltage output from an in vivo muscle contraction that could be sensed and used to coordinate a signal for actuation of a muscle in a separate limb. After designing the appropriate external communication circuitry, a third experiment was performed to verify that a signal between a functional and a denervated muscle can be generated and used as a stimulus.
  
  
  RESULTS
  Voltages below 2 V at a 10-millisecond pulse width elicited a gentle, controlled contraction of the denervated muscle in vivo. It was also observed that with longer pulse widths, higher stimulation voltages were required to produce sufficient contractions.
  
  
  CONCLUSIONS
  It is possible to detect contraction of a muscle, use this to generate a signal to an external base station, and subsequently cause a separate, denervated muscle to contract in response to the signal.
  
  
  CONCLUSIONS
  This demonstration in vivo of a signaling system for pacing of electrical stimulation of 1 muscle to spontaneous contraction of another, separate muscle, using radiofrequency communication without direct connection, may be used in numerous ways to overcome nerve damage.
authors.affiliation: Department of Mechanical Engineering, University of Pittsburgh, Pittsburgh, PA 15236, USA. doreenkjacob@yahoo.com
authors.forename: Doreen K
authors.initials: DK
authors.lastname: Jacob
authors.forename: Susan Tonya
authors.initials: ST
authors.lastname: Stefko
authors.forename: Steven A
authors.initials: SA
authors.lastname: Hackworth
authors.forename: Michael R
authors.initials: MR
authors.lastname: Lovell
authors.forename: Marlin H
authors.initials: MH
authors.lastname: Mickle
mesh_terms: D000818:Animals; D004558:Electric Stimulation; D006614:Hindlimb / Q000294:innervation / Q000503:physiopathology; D009119:Muscle Contraction / Q000502:physiology*; D009121:Muscle Denervation; D018482:Muscle, Skeletal / Q000294:innervation / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013016:Sound