A Disturbance in Sensory Processing on the Affected Side of the Body Increases Limb Pain in Complex Regional Pain Syndrome

AbstractDistorted representations of the body and peripersonal space are common in Complex Regional Pain Syndrome (CRPS), and might modulate its symptoms (e.g. asymmetric limb temperature). In pain-free people, such representations are malleable, and update when we interact with objects in our environment (e.g. during tool-use). Distortions are also common after immobilisation, but quickly normalise once movement is regained. We tested the hypothesis that people with CRPS have problems updating bodily and spatial representations, which contributes to the maintenance of their distorted representations by preventing normalization. We also explored spatially defined modulations of hand temperature asymmetries, and any influence of updating bodily and spatial representations on this effect. Thirty-six people with unilateral CRPS (18 upper limb, 18 lower limb) and 36 pain-free controls completed tool-use tasks considered to alter body and peripersonal space representations (measured using tactile distance judgements and a visuotactile crossmodal congruency task, respectively). We also tested how the arrangement (crossed, uncrossed) of the hands and tools affected hand temperature. In upper limb CRPS the non-affected arm representation updated normally, but the affected arm representation updated in the opposite to normal direction. A similar pattern was seen in lower limbs CRPS, although not significant. Furthermore, people with CRPS showed more pronounced updating of peripersonal space than the controls. We did not observe any modulation of hand temperature asymmetries by the arrangement of hands or tools. Our findings suggest enhanced malleability of bodily and spatial representations in CRPS, potentially implicating central mechanisms in the aetiology of this condition.

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Pain Syndromes Other Than Headache

10.2310/neuro.6177 ◽

2016 ◽

Author(s):

Edgar L. Ross

Keyword(s):

Chronic Pain ◽

Neuropathic Pain ◽

Sensory Processing ◽

Pain Syndrome ◽

The Body ◽

Spinal Cord Dorsal Horn ◽

Opioid Use ◽

Nerve Injuries ◽

Pain Syndromes ◽

Chronic Pain Syndromes

Pain is experienced within a complex biologic, emotional, psychological, and social context that may defy physical examination, diagnostic procedures, and laboratory tests. This chapter aims to empower internists to improve their medical practices in pain management. It provides a scientific background that covers nociception and how sensory processing occurs at multiple levels in the body. Clinical assessment is detailed, as well as diagnostic categories that include mixed or uncertain chronic pain syndromes (back pain, fibromyalgia, postamputation pain, pain from cancer and bone) and neuropathic pain syndromes (polyneuropathy, mononeuropathy multiplex, ganglionopathy, genetic disorders, focal and regional syndromes). Treatment of chronic pain can be surgical or interventional. Pharmacologic treatment for acute and chronic nociceptive pain includes special considerations for geriatric and terminal patients. For treatment of neuropathic pain, medications are the major component. One tables lists iatrogenic nerve injuries that can cause posttraumatic neuralgia and complex regional pain syndrome. Other tables detail stepwise pharmacologic management of neuropathic pain and cite recommendations on opioid use from the Centers for Disease Control and Prevention. One figure illustrates how pain transducers monitor and influence tissue conditions. Other figures show sensory processing in the spinal cord dorsal horn, physical findings in the feet of patients with bilateral foot pain from small-fiber polyneuropathy, illustrate how examination can identify specific nerve injuries causing chronic pain, and provide classification of chronic pain syndromes. This chapter contains 82 references.

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Co-morbidity between trigeminal autonomic cephalalgias and complex regional pain syndrome: Two case reports

Cephalalgia ◽

10.1177/03331024211058204 ◽

2021 ◽

pp. 033310242110582

Author(s):

Peter D Drummond ◽

Philip M Finch

Keyword(s):

Complex Regional Pain Syndrome ◽

Upper Limb ◽

Case Reports ◽

Stellate Ganglion ◽

Pain Syndrome ◽

Pain Modulation ◽

The Body ◽

Trigeminal Autonomic Cephalalgias ◽

Mechanical Stimuli ◽

Co Morbidity

Background Trigeminal autonomic cephalalgias and complex regional pain syndrome are rare conditions, and their co-occurrence has not been reported previously. Clinical findings: In two patients, ipsilateral trigeminal autonomic cephalalgias developed after the onset of upper limb complex regional pain syndrome. Hyperalgesia to thermal and mechanical stimuli extended beyond the affected limb to encompass the ipsilateral forehead, and was accompanied by ipsilateral hyperacusis and photophobia. In addition, examination of the painful limb and bright light appeared to aggravate symptoms of trigeminal autonomic cephalalgias. Detailed examination of the association between facial and upper limb pain indicated that both sources of pain cycled together. Furthermore, in one case, stellate ganglion blockade inhibited pain for an extended period not only in the affected limb but also the face. Conclusions These findings suggest some overlap in the pathophysiology of complex regional pain syndrome and trigeminal autonomic cephalalgias. Specifically, central sensitization and/or disruption of inhibitory pain modulation on the affected side of the body in complex regional pain syndrome might trigger ipsilateral cranial symptoms and increase vulnerability to trigeminal autonomic cephalalgias.

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Complex Regional Pain Syndrome of the Upper and Lower Extremity

10.1093/med/9780190271787.003.0011 ◽

2018 ◽

Author(s):

Agnes Stogicza ◽

Bartha Peter Tohotom ◽

Edit Racz ◽

Andrea Trescot ◽

Alan Berkman

Keyword(s):

Nervous System ◽

Sympathetic Nervous System ◽

Complex Regional Pain Syndrome ◽

Medication Management ◽

Pain Syndrome ◽

The Body ◽

Loss Of Function ◽

Early Presentation ◽

Temperature Changes ◽

Sympathetic Nervous

Complex regional pain syndrome (CRPS) is a chronic debilitating pain condition of the extremities; it can affect, less commonly, other areas of the body (face, pelvis, abdomen). Its early presentation—pain disproportionate to the injury, skin temperature changes, hyperalgesia, allodynia—is often not recognized, delaying treatment. In later phases, with sympathetic nervous system involvement, it presents with skin and muscle atrophy, hair loss, allodynia, loss of function, and decreased range of motion. In severe cases, it can spread from one area to the other. Imaging findings (X-ray, MRI, bone scintigraphy) are nonspecific. They are used to support the diagnosis, and to exclude conditions that can present similarly. Treatment is challenging and includes physical therapy, psychologic support, medication management, and minimally invasive interventions to decrease pain, to positively influence the sympathetic nervous system, and to preserve function. A multidisciplinary approach is likely to be the most beneficial.

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