ABSTRACT
The Charcot joint, or Charcot neuroarthropathy, is a syndrome that was described over 140 years ago but one with very little exposure in the neurologic literature. We present a case recently seen and then discuss the history, epidemiology, pathophysiology, clinical features, and diagnosis of acute and chronic Charcot joint disease with particular emphasis on the value and limitations of imaging. A diagnostic algorithm is proposed. We also review the therapeutic strategies available for acute and chronic Charcot joints with a treatment algorithm. This review is aimed at enhancing the awareness of neurologists regarding Charcot neuroarthropathy, because they are often the principal caregivers for patients with peripheral neuropathy. We hope to promote early detection of acute Charcot neuroarthropathy, thereby reducing or preventing the bony deformation of chronic Charcot neuroarthropathy.
Subject(s)
Arthropathy, Neurogenic/diagnosis , Foot Bones/blood supply , Foot Bones/pathology , Peripheral Nervous System Diseases/diagnosis , Acute Disease , Aged , Arthropathy, Neurogenic/epidemiology , Arthropathy, Neurogenic/physiopathology , Autonomic Nervous System Diseases/diagnosis , Autonomic Nervous System Diseases/epidemiology , Autonomic Nervous System Diseases/physiopathology , Chronic Disease , Diabetic Neuropathies/diagnosis , Diabetic Neuropathies/epidemiology , Diabetic Neuropathies/physiopathology , Disease Progression , Female , Foot Bones/diagnostic imaging , Foot Bones/physiopathology , Humans , Peripheral Nervous System Diseases/epidemiology , Peripheral Nervous System Diseases/physiopathology , RadiographyABSTRACT
RATIONALE: Evidence indicates that social and environmental enrichment can influence the functional maturation of the central nervous system and may affect an organism's sensitivity to centrally acting drugs. OBJECTIVE: The purpose of the present study was to examine the effects of social and environmental enrichment on sensitivity to mu-opioids possessing a range of relative efficacies at the mu-receptor. METHODS: Rats were obtained at weaning (21 days) and divided into two groups immediately upon arrival. Isolated rats were housed individually in opaque laboratory cages with no visual or tactile contact with other rats; enriched rats were housed socially in groups of four in large cages and given various novel objects on a daily basis. After 6 weeks under these conditions, the effects of morphine, levorphanol, buprenorphine, butorphanol, and nalbuphine were examined in the warm-water, tail-withdrawal procedure and the place-conditioning procedure. RESULTS: In the tail-withdrawal procedure, isolated and enriched rats did not differ in sensitivity to morphine (1.0-30 mg/kg) and levorphanol (0.3-10 mg/kg), but enriched rats were more sensitive to buprenorphine (0.03-3.0 mg/kg), butorphanol (0.3-30 mg/kg), and nalbuphine (0.3-30 mg/kg). In drug combination tests, butorphanol and nalbuphine antagonized the effects of morphine in isolated rats under conditions in which they produced high levels of antinociception in enriched rats. In the place-conditioning procedure, doses of 10 morphine and 3.0 levorphanol established a place preference in both groups of rats, whereas doses of 0.3 buprenorphine, 3.0 butorphanol, and 10 nalbuphine established a place preference only in enriched rats. CONCLUSIONS: These findings may be taken as evidence that enriched rats are more sensitive than isolated rats to the effects of lower-efficacy mu-opioids and that social and environmental enrichment leads to functional alterations in opioid receptor populations.