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Updated: Aug 21, 2026

Demonstration of Cutaneous Allodynia in Association with Chronic Pelvic Pain
Published on: June 23, 2009
Spectrum of cutaneous hyperalgesias/allodynias in neuropathic pain patients
R J Verdugo1, L A Bell, M Campero
1Oregon Nerve Center at Legacy Good Samaritan Medical Center, Departments of Neurology and Neurosurgery, Oregon Health and Science University, Portland, OR 97210, USA.
Objectives:
The aim of this study was to discern the pathophysio-logical bases for neuropathic hyperalgesias.
Methods:
In this study, neurological and neurophysiological evaluation of 132 consecutive hyperalgesia patients using rigorous clinical and laboratory protocols were carried out.
Results:
Two discrete semeiologic entities emerged: classic neurological vs atypical, fulfilling taxonomically complex regional pain syndrome (CRPS) II and I, respectively. The classic group (34.9%) exhibited sensorimotor patterns restricted to nerve distribution and documented nerve fiber dysfunction. Among them four (3.03%) had sensitization of C-nociceptors, seven (5.3%) had central release of nociceptive input, and 35 (26.52%) probable ectopic nerve impulse generation. The atypical group (65.1%) displayed weakness with interrupted effort; non-anatomical hypoesthesia and hyperalgesia; hypoesthesia or paresis reversed by placebo, or atypical abnormal movements, and physiological normality of motor and sensory pathways.
Conclusions:
Spatiotemporal features of neuropathic hyperalgesia constitute key criteria for differential diagnosis between CRPS II and I and, together with other behavioral sensorimotor features, signal psychogenic pseudoneurological dysfunction vs structural neuropathology. 'Neuropathic' hyperalgesias may reflect neuropathological or psychopathological disorders.
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