Complex Regional Pain Syndrome type I with atypical scintigraphic pattern — diagnosis and evaluation of the entity with three phase bone scintigraphy. A case report

Abstract

Complex Regional Pain Syndrome (CRPS) is a neurological disorder of unknown etiology which may lead to severe disability. Its diagnosis is very difficult and based on diagnostic criteria which have been changing over last years. Still, there is no golden standard in diagnosis of this entity. Three-phase bone scan is a widely used diagnostic modality which has been proved useful in CRPS evaluation. The syndrome may present various scintigraphic patterns. Different diagnostic modalities can also be helpful when CRPS is suspected including plain film radiography, magnetic resonance imaging and ultrasonography. Multidisciplinary approach is necessary for proper and quick diagnosis. We present a case of CRPS in 12-year-old girl in whom the diagnosis was based on the bone scan.

Review of the Mechanisms of Snake Venom Induced Pain: It’s All about Location, Location, Location

“…Complex and chronic pain syndromes following venomous snake bite are uncommon but debilitating [7,[47][48][49][50][51][52]. These conditions include migraine headache or complex regional pain syndrome (CRPS).…”

“…CRPS, as recently reviewed [90], is a syndrome of ongoing, chronic pain, disproportionate to the original injury (or may be idiopathic), involving peripheral nerve injuries. Three families of venomous snake, Colubridae, Elapidae, and Viperidae, can cause this type of neurotoxicity [47][48][49][50][51][52]. The affected area may exhibit hyperesthesia or allodynia, edema, hair loss, and temperature changes compared to the contralateral body part, and many of these changes are attributed to dysregulation of the sympathetic nervous system [90].…”

“…CRPS treatments are multimodal, involving medications such as steroids, nonsteroidal anti-inflammatory agents, regional nerve blocks, and physical therapy [90]. While the cause of CRPS involves nerve injury, CRPS that occurs secondary to venomous snake bite can be considered both local and remote, as the bite site displays the aforementioned symptoms, but so do proximate parts of the limb bitten [47][48][49][50][51][52]. The nerve injury would be considered direct, and most likely involve acute neurotoxicity from enzymes such as PLA 2 and metalloproteinases that damage tissues structurally and not just physiologically in an easily reversible manner (by antivenom).…”

“…The nerve injury would be considered direct, and most likely involve acute neurotoxicity from enzymes such as PLA 2 and metalloproteinases that damage tissues structurally and not just physiologically in an easily reversible manner (by antivenom). However, it is the indirect and complex mechanisms of the onset of chronic pain that is the neurotoxicity that may last from weeks to years despite therapy [47][48][49][50][51][52]. While the precise molecular mechanisms responsible for how snake venom injures peripheral nerves to the point of causing CRPS and migraine are not well defined, it is likely the improvements in acute management of snake bite may potentially decrease the incidence of this disabling neurotoxicity.…”