Pain
-
Comparative Study
Electronic diaries for monitoring chronic pain: 1-year validation study.
Electronic data collection for monitoring pain has become increasingly popular in clinical research. However, no direct comparison has been made between electronic diaries and self-report paper diaries or phone interviews. We asked 36 patients with chronic low back pain to monitor their pain for 1 year; 20 of them used both a palmtop computer and paper diaries, and 16 used paper diaries alone. ⋯ Two-way messaging available through the palmtop computer seemed to encourage continued use of the device. Internal consistency of reporting and correlations with phone reports and standardized measures were highly significant, suggesting that data from electronic diaries are both reliable and valid. Patients using electronic diaries preferred them to paper diaries and showed much higher rates of compliance and satisfaction over the 1-year trial.
-
Complex regional pain syndrome (CRPS) is characterized by a variety of clinical features including spontaneous pain and hyperalgesia. Increased neuropeptide release from peripheral nociceptors has been suggested as a possible pathophysiologic mechanism triggering the combination of trophic changes, edema, vasodilatation and pain. In order to verify the increased neuropeptide release in CRPS, electrically induced neurogenic vasodilatation and protein extravasation were evaluated in patients and controls. ⋯ The time course of electrically induced protein extravasation in the patients resembled the one observed following application of exogenous substance P (SP). We conclude that neurogenic inflammation is facilitated in CRPS. Our results suggest an increased releasability of neuropeptides in CRPS.
-
Comparative Study
TMJ disorders and myogenic facial pain: a discriminative analysis using the McGill Pain Questionnaire.
Our aim was to assess the discriminative capacity of the McGill Pain Questionnaire (MPQ) in patients with temporomandibular joint (TMJ) disorders or with myogenous facial pain (MP). The MPQ was administered to 57 TMJ and 28 MP patients who were also asked to assess the level of pain using the Visual Analog Scale (VAS). Weighted MPQ item scores, subscale Pain Rating Indexes (PRI), total PRI and the number of words chosen were calculated. ⋯ In conclusion, the MPQ consistently discriminated between TMJ and MP patients. Although the higher affective scores in the MP patients may be partly induced by higher levels of anxiety in these patients, the data convincingly show that the system's discriminative capacity relates to all MPQ subscores and to the majority of the MPQ items. Moreover, within the same item, the choice of verbal descriptors varies consistently between the two groups of patients.
-
Research among persons with cancer pain suggests that the association between pain intensity and pain interference is non-linear. That is, pain begins to have a serious impact on functioning when it reaches a certain threshold level (about 5 on 0--10 scales). Often, a second pain threshold can be identified which, once reached, shows an even greater proportional negative impact on functioning. ⋯ Moreover, the degree of pain interference appeared to vary as a function of pain type. The same level of back pain interfered more significantly with daily function than phantom limb pain did after pain levels reached five or more (on a 0--10 scale). These findings have implications for understanding the meaning of pain intensity levels, as well as for the assessment of pain intensity in persons with amputation-related pain.
-
To investigate the roles of primary afferent fibers in development of the bee venom (BV)-induced persistent spontaneous nociception (PSN) and hyperalgesia (HA), the sciatic nerve or both the sciatic and saphenous nerves of rats were topically treated with capsaicin respectively under pentobarbital anesthesia to destroy the capsaicin-sensitive primary afferent (CSPA) fibers. Effect of the sciatic nerve capsaicin on the formalin-induced PSN was also evaluated. Destruction of the CSPA fibers of the sciatic nerve or both the sciatic and saphenous nerves only produced 34 or 69% inhibition of the mean total number of 1 h BV-induced paw flinches. ⋯ However, destruction of the CSPA fibers of both the sciatic and saphenous nerves was able to block development of both heat and mechanical HA in the whole BV-treated hind paw and heat hyperalgesia in the non-injected hind paw. Taken together, we conclude that: (1) the CSPA (C- and A delta-) fibers play a pivotal role in mediation of either the heat or the mechanical hyperalgesia induced by s.c. BV; (2) the CSPA fibers may play a crucial role in mediation of the formalin-induced PSN, but play a partial role in the BV-induced nociceptive process; (3) in addition to the sciatic nerve, the saphenous nerve is also involved in mediation of the BV-induced PSN as well as heat and mechanical hyperalgesia, while it is not likely to be involved in the formalin-induced nociception.