Peripheral nervous system origin of phantom limb pain

Apostol Vaso, Haim Moshe Adahan, Artan Gjika, Skerdi Zahaj, Tefik Zhurda, Gentian Vyshka, Marshall Devor*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

217 Scopus citations

Abstract

Nearly all amputees continue to feel their missing limb as if it still existed, and many experience chronic phantom limb pain (PLP). What is the origin of these sensations? There is currently a broad consensus among investigators that PLP is a top-down phenomenon, triggered by loss of sensory input and caused by maladaptive cortical plasticity. We tested the alternative hypothesis that PLP is primarily a bottom-up process, due not to the loss of input but rather to exaggerated input, generated ectopically in axotomized primary afferent neurons in the dorsal root ganglia (DRGs) that used to innervate the limb. In 31 amputees, the local anesthetic lidocaine was applied intrathecally and/or to the DRG surface (intraforaminal epidural block). This rapidly and reversibly extinguished PLP and also nonpainful phantom limb sensation (npPLS). Control injections were ineffective. For intraforaminal block, the effect was topographically appropriate. The suppression of PLP and npPLS could also be demonstrated using dilute lidocaine concentrations that are sufficient to suppress DRG ectopia but not to block the propagation of impulses generated further distally in the nerve. PLP is driven primarily by activity generated within the DRG. We recommend the DRG as a target for treatment of PLP and perhaps also other types of regional neuropathic pain.

Original languageEnglish
Pages (from-to)1384-1391
Number of pages8
JournalPain
Volume155
Issue number7
DOIs
StatePublished - Jul 2014

Keywords

  • DRG
  • Ectopic firing
  • Electrogenesis
  • Intraforaminal
  • Neuropathic pain
  • Phantom limb pain

Fingerprint

Dive into the research topics of 'Peripheral nervous system origin of phantom limb pain'. Together they form a unique fingerprint.

Cite this