European journal of pain : EJP
-
Comparative Study
The Short-Form McGill Pain Questionnaire as an outcome measure: test-retest reliability and responsiveness to change.
Abilities of the Short-Form McGill Pain Questionnaire to assess change have scarcely been addressed in previous studies. The aim of the present study was to examine test-retest reliability, sensitivity to change and responsiveness to clinically important change using a Norwegian version (NSF-MPQ) in different groups of patients. ICC(1,1) values for test-retest reliability (relative reliability) assessed 1-3 days apart for total, sensory and affective scores were, respectively, 0.75, 0.76 and 0.62 in patients with musculoskeletal pain (n=58), and 0.93, 0.95 and 0.79 in patients with rheumatic pain (n=25). ⋯ Indication was provided that mean improvement of groups in NSF-MPQ total scores should be >5 on the 0-45 scale to demonstrate a clinically important change. Responsiveness to clinically important change by receiver operating characteristic curve analysis was modest, as area under the curve indicating ability to discriminate improved and not improved patients with musculoskeletal pain, was only 0.61. The study indicates mostly satisfactory test-retest reliability and responsiveness values of the NSF-MPQ, but shows that the measurement properties vary between groups of patients with pain.
-
Comparative Study
Interactions between spatial summation, 2-point discrimination and habituation of heat pain.
Recently, spatial summation (SS) of two discrete noxious stimuli was found to occur at separation distances less than 10cm in the forearm. Interestingly though, with larger separation distances there is 2-point discrimination (2PD) but not SS. However, previous studies have not examined the interactions between these spatial phenomena and temporal aspects of pain. ⋯ However, when the initial pain score was fixed (but the stimulus temperature varied) habituation occurred with all stimulation configurations but significantly less for two probes separated by 0.4cm. Sex was not a factor in SS and 2PD of pain, however there was greater habituation in females than males. In conclusion, SS of pain counteracts 2PD of pain and to a lesser extent, pain habituation.
-
This is the first investigation of the central processing of itch in the brain in 8 subjects with atopic dermatitis (AD) in comparison to 6 healthy controls (HC), comparing histamine-induced itch related activations in the frontal, prefrontal, parietal, cingulate cortex, thalamus, basal ganglia and cerebellum. ⋯ We interpret our findings as possible central correlates of changes in the motor system in subjects with chronic itch, with activation of the basal ganglia possibly correlating to the vicious itch-scratch-circle in subjects with chronic itching skin diseases. However, further neuroimaging studies in healthy subjects and also in different skin diseases are needed to understand the complex mechanisms of the processing of itch.
-
To screen for the presence of latent and active myofascial trigger points (MTrPs) in patients with unilateral shoulder and arm pain and perform topographical mapping of mechanical pain sensitivity bilaterally in the infraspinatus muscles. ⋯ There exists bilateral mechanical hyperalgesia in patients with unilateral shoulder pain. Further, the association of multiple active MTrPs with unilateral shoulder pain and the heterogeneity of mechanical pain sensitivity distribution suggest a crucial role of peripheral sensitization in chronic myofascial pain conditions. Additionally, the locations of MTrPs identified with dry needling correspond well to PPT topographical mapping, suggesting that dry needling and PPT topographical mapping are sensitive techniques in the identification of MTrPs.
-
Little is known of the spinal mechanisms that mediate bone nociception. The aim of this study was to determine the pattern of neuronal activation in the spinal dorsal horn following acute noxious mechanical stimulation of bone. This was achieved by examining Fos expression in the spinal dorsal horn following acute, noxious mechanical stimulation of the rat tibia. ⋯ The number of Fos-LI nuclei in the deep dorsal horn was always lower than the number in the superficial dorsal horn (significant at L3 but not L4; P<0.05). Whilst there appeared to be a small increase in the number of Fos-LI nuclei in the ipsilateral deep dorsal horn of bone drilling and pressure groups relative to the ipsilateral deep dorsal horn control group at both L3 and L4 segments, no significant effect was observed (P>0.05). The present study implicates the superficial dorsal horn of the spinal cord as a region of interest in studies of acute bone pain, and highlights the notion that spinal mechanisms that mediate bone nociception may be different to those that mediate nociception of cutaneous and visceral origin.