title: Cold-induced vasodilatation following traumatic median or ulnar nerve injury.
abstract: OBJECTIVE
  Peripheral nerve injury of the upper extremity frequently causes changes in the thermoregulatory system of the hands and fingers and leads to reports of cold intolerance. In this study, we aimed to measure the influence of median or ulnar nerve injury on cold-induced vasodilatation (CIVD) during prolonged cooling at low temperatures.
  
  
  METHODS
  We tested 12 patients with a median (n = 6) or ulnar (n = 6) injury 4 to 76 months after nerve repair. The palmar sides of both hands were cooled continuously using a cold plate at 5°C. We measured the skin temperature of the fingers using videothermography and plotted graphs of the temperature changes of the nailbed. The presence of a CIVD reaction was defined as a minimum increase in temperature of 2.5°C starting at the distal phalanx. Furthermore, we measured self-reported symptoms of cold intolerance using the Cold Intolerance Severity Scale questionnaire.
  
  
  RESULTS
  A CIVD reaction was absent in the affected digits of 4 patients (follow-up, 6-37 mo), whereas the CIVD reaction in the uninjured hand was present. The CIVD was present in 6 patients after 50 months' follow-up (range, 24-76 mo). Two patients had no CIVD reaction in the injured or uninjured fingers. All patients with a CIVD response had at least diminished protective sensation. Presence of the CIVD reaction did not exclude self-reported symptoms of cold intolerance.
  
  
  CONCLUSIONS
  After peripheral nerve injury, it is possible to recover the CIVD reaction. This might be an indication of nerve recovery. However, a positive CIVD reaction does not exclude subjective symptoms of posttraumatic cold intolerance.
  
  
  METHODS
  Diagnostic III.
authors.affiliation: Department of Plastic, and the Department of Anesthesiology, Pain Treatment Centre, Erasmus MC, Rotterdam, The Netherlands. aleidruijs@hotmail.com
authors.forename: Aleid C J
authors.initials: AC
authors.lastname: Ruijs
authors.forename: Sjoerd P
authors.initials: SP
authors.lastname: Niehof
authors.forename: Steven E R
authors.initials: SE
authors.lastname: Hovius
authors.forename: Ruud W
authors.initials: RW
authors.lastname: Selles
mesh_terms: D000293:Adolescent; D000328:Adult; D001833:Body Temperature Regulation / Q000502:physiology; D003080:Cold Temperature / Q000009:adverse effects*; D005260:Female; D005385:Fingers / Q000098:blood supply*; D005500:Follow-Up Studies; D006225:Hand / Q000098:blood supply*; D006801:Humans; D008297:Male; D008475:Median Nerve / Q000293:injuries* / Q000601:surgery; D008866:Microsurgery; D008875:Middle Aged; D009416:Nerve Regeneration / Q000502:physiology; D011183:Postoperative Complications / Q000503:physiopathology; D012684:Sensory Thresholds / Q000502:physiology; D013817:Thermography; D014459:Ulnar Nerve / Q000293:injuries* / Q000601:surgery; D014664:Vasodilation / Q000502:physiology*; D055815:Young Adult