Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Complex regional pain syndrome (CRPS) is the complication of some injuries, such as a fracture, which affects the distal end of the injured extremity characterized by pain, allodynia, hyperalgesia, edema, abnormal vasomotor and sudomotor activity, movement disorders, joint stiffness, regional osteoporosis, and dystrophic changes in soft tissue. Exact pathogenic mechanism of CRPS is still unclear. Suggested pathogenic mechanisms of CRPS are evaluated in four major groups consist of classic inflammation, hypoxic changes and chronic ischemia, neurogenic inflammation and sympathetic dysregulation. All of these suggested pathogenic mechanisms produced by inflammatory cytokines mediated by nuclear factor kappaB. Vitamin K is a family of structurally similar, fat-soluble, 2-methyl-1,4-naphthoquinones. Vitamin K exerts a powerful influence on bone formation, especially in osteoporosis. Fat in bone stores some vitamin K. Gamma-carboxylation of the glutamic acid in osteocalcin is vitamin K dependent. Osteocalcin plays a role in calcium uptake and bone mineralization. Osteocalcin, the most abundant non-collagenous protein in bone, is produced by osteoblasts during bone matrix formation. Because osteocalcin is not carboxylated in case of vitamin K deficiency at the distal site of fracture or injury, it cannot bind to hydroxyapatite causing osteoporosis. Fracture starts a local inflammatory process in the fracture site and adjacent tissues as seen in CRPS. Vitamin K was shown to suppress the inflammatory cytokines and NF-kappaB and prevent oxidative, hypoxic, ischemic injury (which have key role in both initiation and progression of CRPS) to oligodendrocytes and neurons. We hypothesized that vitamin K has a key role and modulatory effect in CRPS pathogenesis. Vitamin K deficiency at the distal site of fracture occurs because of diminished and slowed circulation, local immobilization after extremity fracture or injury and use of vitamin K store at the distal site of the injured extremity and in the circulation for fracture healing and bone remodelling. In case of vitamin K deficiency at the distal site of fracture, classic inflammation starts with fracture at the distal tissues could not be restricted and classic inflammation, hypoxic changes, chronic ischemia, neurogenic inflammation, sympathetic dysregulation, which are the pathogenic mechanisms of CRPS, and patchy osteoporosis which occur due to high level of under-carboxylated osteocalcin could not be prevented. Briefly vitamin K level decreases in the distal site of the injured extremity consequently resulting in patchy osteoporosis due to high level of under-carboxylated osteocalcin and unrestricted inflammation which are the cause for both initiation and progression of CRPS.
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PMID:Complex regional pain syndrome: a vitamin K dependent entity? 2037 61

Digital tourniquet is a quick, simple and reliable method to ensure a bloodless operative field distal to the MP joint. However, a forgotten tourniquet is an exceptional but serious complication related to digital ischemia. Few cases were reported in literature without a long-term outcome. Three digits of three patients, aged 70, 49 and 14 at the time of accident, had a tourniquet left in place for 2 days for the first two and 6 days for the last one. Final assessment was carried out 3, 4 and 16 years respectively after the initial accident. All fingers survived with sequelae such as pain, cold intolerance, dysesthesia, allodynia, joint stiffness and skin and nail trophic disorders. A hypertrophic scar was still visible at the site of the tourniquet. Capillary pulse was normal in all cases. Radiological changes were visible when the tourniquet had been left for more than 2 days. The impact on professional and day life activities was considerable. No surgery for the sequelae was done. Avoiding a missed finger tourniquet requires a suitable tourniquet with a visual reminder and its removal must be considered a crucial part of the surgery.
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PMID:[Long-term functional outcomes of digital ischemia under tourniquet: observations in three cases]. 2318 85