title: Thoracolumbar multisegmental motor responses in the upper and lower limbs in healthy subjects.
abstract: METHODS
  Experimental design.
  
  
  OBJECTIVE
  This descriptive study presents muscular responses from both the upper and the lower extremities during T11-12 segmental stimulation.
  
  
  METHODS
  Neuro Lab of the Texas Woman's University (School of Physical Therapy, TX, USA).
  
  
  METHODS
  A total of 13 healthy subjects were electrically stimulated using surface electrodes. In trial 1, signals were recorded from the flexor hallucis brevis, soleus, vastus medialis and gluteus medius in the lower right extremity. In trial 2, responses were recorded from the abductor digiti minimi, abductor pollicis brevis (APB), flexor carpi radialis and biceps brachii in the right upper extremity. In trial 3, stimulation was carried out and signals were recorded for both the upper and the lower extremities simultaneously, using different muscle combinations. Five traces per muscle were averaged for each step of the testing. Amplitude and deflection latency were the measured parameters and were compared using descriptive statistics.
  
  
  RESULTS
  Results showed signal amplitudes ranging from 85 to 821 μV in the upper extremity and from 582 to 3927 μV in the lower extremity, with the largest signal recorded in the soleus muscle and the APB. Response latency varies between 5.5 and 14 ms in the upper limbs and between 7.7 and 27 ms in the lower limbs and was comparable in bilateral recording.
  
  
  CONCLUSIONS
  These muscular responses seem to be elicited from electrical stimulation of motor nuclei in lower limb muscles or from pathways to those nuclei in upper limb muscles, and could be useful in testing patients with spinal disorders.
authors.affiliation: School of Physical Therapy, Texas Woman's University, Houston, TX 77030, USA. msabbahi@twu.edu
authors.forename: M A
authors.initials: MA
authors.lastname: Sabbahi
authors.forename: Y S
authors.initials: YS
authors.lastname: Sengul
mesh_terms: D000328:Adult; D001132:Arm / Q000294:innervation / Q000502:physiology*; D005260:Female; D006801:Humans; D007866:Leg / Q000294:innervation / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009046:Motor Neurons / Q000502:physiology*; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000294:innervation / Q000502:physiology*; D052097:Quadriceps Muscle / Q000294:innervation / Q000502:physiology; D012016:Reference Values; D013116:Spinal Cord / Q000502:physiology*; D055815:Young Adult