title: Ulnar motor study to first dorsal interosseous: Best reference electrode position and normative data.
abstract: BACKGROUND
  Reference electrode position affects nerve conduction study results. This study was undertaken to determine the optimal reference electrode position for ulnar motor recording from the first dorsal interosseous (FDI) muscle and to develop normative data.
  
  
  METHODS
  Fifty-one subjects were tested using reference electrode positions on the thumb, index, and little fingers. Latencies were compared with a needle recording from the FDI. Analysis was performed to determine the surface placement that most closely matched the needle recording latency. A normative database was then derived on 100 healthy subjects.
  
  
  RESULTS
  Placing the reference electrode on the thumb yielded results closest to the "gold standard" needle recording latency. The 97th percentile (upper limit of normal) for latency was 4.0 ms. The 3rd percentile values (lower limit of normal) for amplitude were 9.0 mV for men and 9.3 mV for women.
  
  
  CONCLUSIONS
  The reference position on the thumb yields latencies that most closely approximate needle recording. Normative data are presented.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Indiana University School of Medicine, Goodman Hall, 355 West 16th Street, Suite 4700, Indianapolis, Indiana, 46202, USA.
authors.forename: Ralph M
authors.initials: RM
authors.lastname: Buschbacher
authors.affiliation: Department of Rheumatology, Faculty of Medicine, Ege University, Izmir, Turkey.
authors.forename: Ozun
authors.initials: O
authors.lastname: Bayindir
authors.affiliation: Department of Physical Medicine and Rehabilitation, Indiana University School of Medicine and Rehabilitation Hospital of Indiana, Indianapolis, Indiana, USA.
authors.forename: James
authors.initials: J
authors.lastname: Malec
authors.affiliation: Department of Physical Medicine and Rehabilitation, Faculty of Medicine, Marmara University, Istanbul, Turkey.
authors.forename: Gulseren
authors.initials: G
authors.lastname: Akyuz
mesh_terms: D000328:Adult; D000368:Aged; D004558:Electric Stimulation / Q000379:methods; D004566:Electrodes / Q000592:standards; D005260:Female; D006225:Hand / Q000294:innervation* / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009431:Neural Conduction / Q000502:physiology*; D014459:Ulnar Nerve / Q000502:physiology*; D055815:Young Adult
keywords: deep palmar branch of the ulnar nerve; electrodiagnosis; first dorsal interosseous muscle; nerve conduction study; ulnar nerve