Pain
-
Comparative Study
Spatial summation of heat pain within and across dermatomes in fibromyalgia patients and pain-free subjects.
The mechanisms of spatial summation of pain (SSP) include pain coding dependent on impulse frequency and the number of recruited central neurons. However, SSP may also be influenced by pain inhibitory mechanisms, such as diffuse noxious inhibitory controls. Abnormal interactions between pain inhibitory mechanisms and SSP may be relevant for chronic pain conditions such as fibromyalgia (FM) and may help explain why widespread pain is characteristic for this chronic pain syndrome. ⋯ Furthermore, SSP was more pronounced within one dermatome such as that of the index finger than across several dermatomes of the hand. These results were similar for both FM and NC subjects. Thus, mechanisms of SSP, including possible inhibitory factors that limit this relevant pain mechanism, appear to be similar for both FM and NC subjects.
-
Comparative Study
Can one predict the likely specific orofacial pain syndrome from a self-completed questionnaire?
To estimate the prevalence of orofacial pain (OFP) by specific diagnostic subgroups in the general population. Cross-sectional population study. General medical practice in South East Cheshire, UK. ⋯ The estimated prevalence in the general population of musculoligamentous/soft tissue type of OFP was 7%, dentoalveolar 7% and neurological/vascular 6%. This study has derived a statistical model to classify participants with OFP into three broad groups (musculoligamentous/soft tissue, dentoalveolar and neurological/vascular) based on questionnaire information about OFP (OFP chronicity, location and verbal descriptors of pain). It is potentially useful in large population studies of OFP, where a clinical examination is not possible, however, further validation of its performance in large populations are necessary.
-
Comparative Study
Self-efficacy, fear avoidance, and pain intensity as predictors of disability in subacute and chronic musculoskeletal pain patients in primary health care.
This study examined the relations between disability, as measured by the Pain Disability Index (PDI) and self-efficacy, fear avoidance variables (kinesiophobia and catastrophizing), and pain intensity, using a prospective design. Two primary health care samples (n(1)=210; n(2)=161) of patients with subacute, chronic or recurring musculoskeletal pain completed sets of questionnaires at the beginning of a physiotherapy treatment period. Multiple hierarchial regression analyses showed that self-efficacy explained a considerably larger proportion of the variance in disability scores than the fear avoidance variables in the first sample. ⋯ Gender, age, and pain duration were not related to disability. These findings suggest that self-efficacy beliefs are more important determinants of disability than fear avoidance beliefs in primary health care patients with musculoskeletal pain. The findings also suggest that pain-related beliefs, such as self-efficacy and fear avoidance, in turn, are more important determinants of disability than pain intensity and pain duration in these patients.
-
Comparative Study
Development of tactile allodynia and thermal hyperalgesia by intrathecally administered platelet-activating factor in mice.
Platelet-activating factor (PAF) is a potent inflammatory lipid mediator in peripheral tissues. However, its role in mediation of nociception in central nervous system is unknown. In the present study, whether PAF plays some role in pain transduction in the spinal cord was studied in mice. ⋯ PAF-induced tactile allodynia and thermal hyperalgesia disappeared in neonatally capsaicin-treated adult mice, while tactile allodynia but not thermal hyperalgesia induced by intrathecally injected alpha,beta-methylene ATP, a P2X receptor agonist, was capsaicin-insensitive. The present study demonstrated that PAF is a potent inducer of tactile allodynia and thermal hyperalgesia at the level of the spinal cord. PAF-evoked tactile allodynia is suggested to be mediated by ATP and the following NMDA and NO cascade through capsaicin-sensitive fiber, different from exogenously injected alpha,beta-methylene ATP which is insensitive to capsaicin treatment.
-
Our objective was to determine the efficacy and safety of valdecoxib (a cyclo-oxygenase 2 inhibitor) in the treatment of arthritis. Randomised, controlled trials comparing 10 or 20mg valdecoxib with placebo or non-steroidal anti-inflammatory drugs (NSAIDs) in patients with active osteoarthritis or rheumatoid arthritis. The manufacturer provided clinical trial reports. ⋯ At an appropriate dose valdecoxib was as effective as NSAIDs in osteoarthritis and rheumatoid arthritis. There were fewer gastrointestinal adverse event withdrawals and endoscopically detected ulcers. Convincing evidence of reduced major gastrointestinal adverse events could not be addressed by the trials.