Journal of rehabilitation research and development
-
Management of neuropathic pain remains problematic; however, cell therapy to treat the effects of pain on the sensory system after spinal cord injury (SCI) could be a useful approach. Since many clinical trials ultimately do not succeed, use of cell therapy will require that safety and efficacy issues be addressed early in preclinical rat studies. We used the human neuronal cell line hNT2.17, which secretes the inhibitory neurotransmitters gamma-aminobutyric acid and glycine, in an excitotoxic SCI pain model after intraspinal injection of quisqualic acid into rats. ⋯ Antinociceptive grafts displayed an optimal transplant time that included moderate effectiveness with chronic SCI and late graft placement and that required a minimal course of cyclosporine A 2 weeks after transplant for durable reversal of painlike behaviors. In addition, grafts did not need to be placed near the SCI level to be effective. These data suggest not only that these cells are safe and efficacious but also that they could be an effective clinical tool for treating SCI-associated neuropathic pain.
-
Blasts are responsible for about two-thirds of the combat injuries in Operation Iraqi Freedom and Operation Enduring Freedom, which include at least 1,200 traumatic brain injuries. Blasts inflict damage to the brain directly and by causing injuries to other organs, resulting in air emboli, hypoxia, and shock. Direct injuries to the brain result from rapid shifts in air pressure (primary blast injury), from impacts with munitions fragments and other objects propelled by the explosion (secondary blast injury), and from collisions with objects and rapid acceleration of individuals propelled by the explosion (tertiary blast injury). ⋯ The damage attributable to the specific effects of a blast, however, has received little study, although it has been assumed to include the focal and diffuse lesions characteristic of closed head injuries. Available clinical studies of blast injuries show focal damage similar to that found in other types of closed head injuries but have not determined whether diffuse axonal injury also occurs. In this article, we will try to reach a better understanding of the specific pathology of blast-related brain injury by reviewing the available experimental studies and the autopsy reports of victims of terrorist attacks and military casualties dating back to World War I.
-
Published studies have reported widely divergent estimates of the prevalence of chronic pain among individuals with (traumatic) spinal cord injury (SCI). To develop an estimate based on a synthesis of the research, we used searches of MEDLINE, CINAHL, PsycINFO, and other bibliographic databases and an ancestor search to identify articles published since 1966 in any language that reported a pain prevalence rate for at least 30 subjects with certain or likely traumatic SCI. Data on sample makeup, study quality indicators, and pain prevalence were abstracted independently by two researchers. ⋯ Pain prevalence in the combined samples did not appreciably differ between males and females, those with complete versus incomplete SCI, and those with paraplegia versus tetraplegia. We conclude that too much heterogeneity was present in the reports to calculate a post-SCI pain prevalence rate using meta-analytic methods. Further research is needed to determine whether rates are related to sample makeup (e.g., average subject age), research methods used (e.g., telephone interview vs self-report instruments), or even the definition of "chronic" pain.
-
This study examines the psychological characteristics of a cohort of individuals with spinal cord injury (SCI) and persisting pain referred to a tertiary pain management center. Forty-five individuals completed measures of pain, mood, disability, and both pain- and SCI-related psychological variables such as self-efficacy and catastrophizing. Compared with a general pain clinic population attending the same tertiary pain management center (n = 5,941), the sample was found to have lower pain intensity, comparable pain catastrophizing levels, and less activity interference due to pain. ⋯ Pain catastrophizing was associated with anxiety, depression, and activity interference due to pain; pain self-efficacy was close to being significantly associated with these variables also. SCI acceptance and self-efficacy were also associated with some of these variables. These findings suggest that the biopsychosocial model of pain is applicable in this sample and that further treatment benefits could be obtained through use of interventions targeting psychological and social variables within this model.
-
Serotonin in the spinal cord acutely modulates nociceptive transmission and motor reflexes and may also assist functional restoration after spinal cord injury (SCI). It is released there mainly by descending axons of the medulla's nucleus raphe magnus (NRM). We examined whether mechanical allodynia (cutaneous hypersensitivity) after incomplete SCI is sustainably reversed by prolonged, intermittent electrical stimulation of the NRM and whether altered NRM activity accounts for the allodynia. ⋯ Neurons inhibited from dermatomes above the injury were excited from below. Altered NRM activity is unlikely to cause SCI allodynia, since inhibited and excited classes are believed to oppositely modulate nociception. Prolonged, early NRM stimulation probably reverses above-injury allodynia by facilitating qualitative recovery of remaining tissue.