Pharmacokinetic profiles of 5 mg/kg ibudilast, a phosphodiesterase inhibitor, orally administered to dogs in fasted and non-fasted states. A preliminary study.

Ibudilast (AV-411) is a non-selective inhibitor of cyclic nucleotide phosphodiesterase (PDE). It is currently marketed for human use in Asian countries for the treatment of asthma, cerebrovascular disorders and ocular allergies. Ibudilast has also been found to have an analgesic action for neuropathic pain at doses 5-10 times higher than those used in asthma therapy. Six healthy Labrador dogs were randomly assigned to two treatment groups using an open, single-dose, two-treatment, two-phase, cross-over design (2x2 Latin-square). Dogs in group 1 (n=3) were fasted for at least 10 hours overnight before the beginning of the experiment and 4 h following dosing while dogs in group 2 (n=3) received food ad libitum. During the first phase, each dog in group 1 and 2 received a single dose of 5 mg/kg ibudilast administered orally. After 1-week washout period the groups were rotated and the experiment was repeated. The analytical method, validated for dog plasma, was shown to be linear in the range 0.10-20 µg/mL. The limit of detection (LOD) and quantification (LOQ) were 0.03 and 0.1 µg/mL, respectively. No behavioural or health alterations were observed in the animals during or after the study. Ibudilast was detectable in plasma for up to 24 h showing a wide variability between animals. Although no statistically significant differences were observed in the present study between the fed and fasted states, examination of the raw data suggests that an effect may be present. The wide degree of variation observed in area under the curve (AUC) suggests that the investigation of population pharmacokinetic modelling is warranted.

Pharmacokinetic profiles of the analgesic drug flupirtine in cats.

Flupirtine (FLU) is a non-opioid analgesic drug with no antipyretic or antiphlogistic effects, used in the treatment of a wide range of pain states in human beings. There is a substantial body of evidence on the efficacy of FLU in humans but this is inadequate to recommend its off-label use in veterinary clinical practice. The aim of this study was to evaluate the pharmacokinetic profiles of FLU after IV and PO administration in healthy cats. Six mixed breed adult cats were randomly assigned to two treatment groups using an open, single-dose, two-treatment, two-phase, paired, cross-over design (2 × 2 Latin-square). Group 1 (n = 3) received a single dose of 5 mg/kg of FLU injected IV into the jugular vein. Group 2 (n = 3) received the same dose via PO route. The wash out period was 1 week. Blood samples (1 mL) were collected at assigned times and plasma was then analysed by a validated HPLC method. No adverse effects at the point of injection and no behavioural changes or alterations in health parameters were observed in the animals during or after the study (up to 7 days after the full study). After IV administration, FLU was detectable in plasma up to 36 h. After PO administration, FLU plasma concentrations were lower than those following IV administration, but they were detectable over the same time range. The terminal part of both mean pharmacokinetic curves showed a similar trend of elimination. The oral bioavailability was approximately 40%. This is the first study of FLU in an animal species of veterinary interest and it could pave the way for the use of this active ingredient in the veterinary field.

Pharmacokinetic profiles of the novel COX-2 selective inhibitor cimicoxib in dogs.

Cimicoxib (CX) is a novel imidazole derivative that is a cyclo-oxygenase (COX)-2 selective non-steroidal anti-inflammatory drug and the latest COX-2 selective inhibitor to be released for veterinary use. Currently there is limited information available on the pharmacokinetic (PK) properties of CX. The aim of the current study was to evaluate the PK features of CX after administration of the recommended dose and after administration of a more variable dose rate in the form of the commercially available tablet. In addition, the effects of food intake on the PK properties were also evaluated. In the first study, five healthy Beagle dogs received 2mg/kg CX via the oral route following a period of fasting. The second study was conducted using six healthy Labrador retriever dogs which each received an 80 mg tablet (approximate dose 1.95-2.5mg/kg) using a crossover design, both in the fasted and fed condition. The plasma concentrations of CX were detected by a validated HPLC method. No adverse effects were observed in any dogs during the experiment. The results from the PK analysis were similar between the studies, regardless of precision of dose and fasted and fed conditions. The mean peak concentration of CX was 0.49 and 0.43 µg/mL under fasted and fed conditions, respectively. The mean half-life was about 3h after all treatments. In addition, simulated multiple dosing data revealed that time over minimal effective concentration was similar after 1.95, 2.0 and 2.5mg/kg dose administrations. These findings suggest that slight variation from the recommended dose should not alter the therapeutic outcome. In addition, CX can be administered to fed dogs without significantly affecting blood levels.

Residue depletion of sulfachlorpyrazine in edible tissues of broiler chickens.

The residue depletion profile of sulfachlorpyrazine was studied in healthy broilers after oral administration of Sulfatyf®, given at a dose of 50 mg sulfachlorpyrazine (SCP) per kg body weight once daily for 3 consecutive days. Twenty-five medicated broilers were slaughtered on the 5th, 10th, 14th and 16th day of post-medication, and muscle, fat with skin, liver and kidney tissues were sampled and analysed using an high-performance liquid chromatography (HPLC) method with satisfactory recovery (74.5% ± 2.9%) and specificity. The estimated values of LOD and LOQ were 18.40 and 55.70 ng ml(-1), respectively. On the 5th and 10th day of post-medication, the concentrations of SCP residue in all samples examined were higher than the corresponding MRLs established by the European Union and the highest SCP concentrations were measured in muscle. A maximum withdrawal time of 14 days was calculated to ensure consumer safety.

Diurnal and seasonal changes in endogenous melatonin levels in the blood plasma in dogs.

This paper describes research on the levels of endogenous melatonin (MLT) in the blood serum in dogs in different seasons (March, June, September, December) and at different times of day (11:00, 12:00, 23:00, 24:00 and 1:00), using immunoassay method. Blood samples were collected in the diurnal cycle, in consecutive seasons. The conducted studies show that MLT levels undergo clear changes in both the diurnal cycle, as well as in seasonal one in this species.

Sulfachlorpyrazine residues depletion in turkey edible tissues.

Sulfachlorpyrazine (SCP) is currently used to treat coccidian infections in turkeys; however, there is no information available about the withdrawal period necessary for the turkey to be safe for human consumption. A high performance liquid chromatography method with ultraviolet-visible light detection was adapted and validated for the determination of SCP in turkey tissues. The procedure is based on isolation of the (SCP sodium) compound from edible turkey tissues (muscles, liver, kidneys, and fat with skin) with satisfactory recovery (72.80 +/- 1.40) and specificity. The residue depletion of SCP in turkeys was conducted after a dose of 50 mg/kg body weight/day had been administrated orally for 3 days. After treatment has been discontinued residue concentrations were detected in tissues on the 7th day. The highest SCP concentrations were measured in muscles. Based on the results presented in this study, it could be assumed that a withdrawal period of 21 days, before medicated turkeys could be slaughtered, would be sufficient to ensure consumer safety.

Pharmacokinetics of tramadol and metabolites after injective administrations in dogs.

The aim of this study was to determine the pharmacokinetics of tramadol and its main metabolites after i.v. and i.m. injections. The pharmacokinetic cross-over study was carried out on 6 healthy male beagle dogs. Tramadol was administered by intravenous (i.v.) and intramuscular (i.m.) injection at 4 mg/kg. Tramadol and its main metabolites O-desmethyl-tramadol (M1), N-,N-didesmethyl-tramadol (M2) and N-,O-didesmethyl-tramadol (M5) concentrations were measured in plasma samples by a HPLC coupled with fluorimetric detection; pharmacokinetic evaluations were carried out with a compartmental and non-compartmental model for tramadol and its metabolites, respectively. The bioavailability of the drug, ranging between 84-102% (mean 92%), was within the generally accepted values for a positive bioequivalence decision of (80-125%). After the i.m. injection the mean plasma drug concentration peak was reached after a T(max) of 0.34 h with a C(max) of 2.52 microg/mL. No therapeutic relevant differences were observed between i.m. and i.v. administration. The minimal effective plasma concentration was reached after a few minutes and maintained for about 6-7 h in both administrations. M1 plasma concentration was low and the amounts of the other metabolites produced were analogous in both routes of administration. In conclusion, tramadol was rapidly and almost completely absorbed after i.m. administration and its systemic availability was equivalent to the i.v. injection. The different onset time and duration of action observed were very small and probably therapeutically irrelevant. The i.m. injection is a useful alternative to i.v. injection in the dog.

Pharmacokinetics of tramadol and its major metabolites following rectal and intravenous administration in dogs.

AIM: To compare the rectal and I/V administration of tramadol in dogs, to assess both its pharmacokinetic properties and absolute bioavailability. METHODS: After rectal administration via suppositories and I/V injection of tramadol (4 mg/kg), the concentration of tramadol and its main metabolites, O-desmethyl-tramadol (M1), N-desmethyl-tramadol (M2) and N,O-didesmethyl-tramadol (M5), were determined in plasma, using high-performance liquid chromatography (HPLC). A balanced cross-over study was used, involving six male Beagle dogs. RESULTS: Plasma concentrations after rectal and I/V administration were fitted on the basis of mono- and bi-compartmental models, respectively. Following rectal administration tramadol was detected from 5 minutes up to 10 hours, in lesser amounts than M5 and M2, while M1 was detected in negligible amounts. Following I/V administration tramadol was detected up to 10 hours, M2 and M5 were detected at similar concentrations, and M1 was present at low concentrations. The area under the curve (AUC) of the three metabolites did not differ significantly after either route of administration of tramadol. The absolute bioavailability of tramadol via rectal administration was 10 (SD 4)%. CONCLUSIONS: After rectal administration of tramadol suppositories, absorption of the active ingredient was rapid, but its metabolism quickly transformed the parent drug to high levels of M2 and M5. CLINICAL RELEVANCE: In the dog, rectal pharmaceutical formulation of tramadol would have a different pharmacokinetic behaviour than in humans.

Pharmacokinetic and urine profile of tramadol and its major metabolites following oral immediate release capsules administration in dogs.

The aim of the present paper was to test the oral administration of oral immediate release capsules of tramadol in dogs, to asses both its pharmacokinetic properties and its urine profile. After capsules administration of tramadol (4 mg/kg), involving eight male Beagle dogs, the concentration of tramadol and its main metabolites, M1, M2 and M5, were determined in plasma and urine using an HPLC method. The plasma concentrations of tramadol and metabolites were fitted on the basis of mono- and non-compartmental models, respectively. Tramadol was detected in plasma from 5 min up to 10 h in lesser amounts than M5 and M2, detected at similar concentrations, while M1 was detected in negligible amounts. In the urine, M5 and M1 showed the highest and smallest amount, respectively; M1 and M5 resulted widely conjugate with glucuronic acid. In conclusion, after oral administration of tramadol immediate release capsules, the absorption of the active ingredient was rapid, but its rapid metabolism quickly transformed the parental drug to high levels of M5 and M2, showing an extensive elimination via the kidney. Hence, in the dog, the oral immediate release pharmaceutical formulation of tramadol would have different pharmacokinetic behaviour than in humans.

High performance liquid chromatography determination of sulphachloropyrazine residues in broiler and turkey edible tissues.

A HPLC method to determine and quantify sulphachloropyrazine residues from broilers and turkeys is reported. This procedure permitted sulphachloropyrazine to be separated from muscle tissue, liver, kidneys and fat with skin after extraction with dichloromethane under slightly acidic conditions. The analytical methodology showed a high specificity and sensitivity and an adequate precision and accuracy with a limit of quantification of 56 ng mL(-1). The peak area showed a linear relationship with a concentration over the range 50-750 ng mL(-1) for sulphachloropyrazine standard solutions. Recovery dates were also satisfactory with values between 69.7 and 77.5%.

Habituation of the early pain-specific respiratory response in sustained pain.

Neurokinin-1 receptor and mu-opioid receptor agonists affect respiratory rhythm when injected directly into the preBötzinger brainstem complex, which is the hypothesized site for respiratory rhythmogenesis in mammals (Science 286 (1999) 1566). Early stress-induced analgesia (SIA) is naloxone-insensitive and as such considered independent of the activation of the mu-opioid system. Prolonged application of electrical shocks, however, produces analgesia that is mediated by the mu-opioid system (Science 208 (1980) 623). Together these findings suggest that any early pain-specific increased respiration should be attenuated in the tonic state of pain. Ten healthy, pain-free female volunteer subjects participated in this experimental study involving deep acute and tonic pain. The experimental design included three conditions: (1) baseline; (2) pain; and (3) a placebo control stimulus. Experimental pain was induced by the infusion of hypertonic saline into the masseter muscle. Infusion of isotonic saline in the contralateral masseter was used as a control. Blinded subjects were randomly assigned to a particular sequential order of the experimental stages, i.e. hypertonic saline infusion preceded the isotonic saline infusion or vice versa. Respiration rate, mean peak inspiratory and expiratory flow rates, and the minute ventilation volume quantified breathing. Results indicate that effects on respiration were pain-specific and that the early effects on respiration were significantly attenuated in sustained pain. In the early stage of pain, all monitored variables (respiration rate, minute ventilation volume, and inspiratory and expiratory flow rates) were elevated to statistically significant degrees when compared to measurements taken at baseline or during control infusion. Only respiration rate continued to be significantly elevated in sustained pain. We concluded that rhythmogenic neurons in the preBötzinger brainstem complex appear as the likely target for pro-nociceptive and anti-nociceptive input, explaining both the observed initial facilitation and subsequent habituation of respiration in early and sustained pain.

Generic pain intensity scores are affected by painful comorbidity.

AIMS: To determine the degree to which the generic pain intensity rating (i.e., overall and without reference to a particular body site) of facial pain patients being seen in a specialty setting for facial pain is influenced by painful comorbidity in body parts other than the face. METHODS: In this prospective study, 40 consecutive female temporomandibular pain patients rated their generic pain on a 100-mm visual analog scale. After marking all painful body sites on pain drawings, patients were asked to rate the pain intensity for each of the indicated pain sites; the patients did not have access to the generic pain intensity score. Pearson's correlation coefficient was used to correlate the generic pain intensity score with site-specific pain intensity ratings, their mean and maximum, and the number of pain sites. RESULTS: The medians of the generic, maximum, and facial pain intensity scores were 49.5, 53, and 45.5, respectively. The generic pain intensity rating correlated more highly with the intensity scores reported for the most painful body site (r2 = 0.82; P < 0.001) than with the average rating across all painful sites (r2 = 0.62; P < 0.001), or the pain intensity score in the face (r2 = 0.61; P < 0.001). The number of pain sites did not correlate to any statistically significant degree with the generic pain intensity rating (r2 = 0.006; P = 0.65). CONCLUSION: The results of this study suggest that the maximum visual analog scale pain intensity score, observed in any body location, is a better reflection of the generic pain intensity rating than the corresponding score of the face. To avoid over-rating or underrating of facial pain intensity, patients should be instructed to provide site-specific pain intensity scores if painful comorbidity is present.

Humoral immunity to stress proteins and periodontal disease.

BACKGROUND: There is evidence that microbial heat shock (stress) proteins (Hsp) are immunodominant antigens of many microorganisms. Immunity to these proteins has been shown in non-oral infections to contribute to protection. This study was undertaken to assess the relationship(s) between immunity to human and microbial heat shock proteins, periodontal disease status, and colonization by periodontal disease-associated microorganisms. METHODS: Subgingival plaque and blood samples obtained from 198 patients during an earlier clinical study were examined for the presence of specific periodontal disease-associated microorganisms and antibodies to selected human and microbial heat shock proteins (Hsp70, Hsp90, DnaK, and GroEL). Particle concentration immunofluorescence assay (PCFIA) was used to detect anti-Hsp antibodies and slot immunoblot assay (SIB) was used to detect subgingival plaque species. Regression models were used to examine the contribution of age, gender, gingival index, probing depth, attachment loss, calculus index, plaque index, and microbial colonization to the anti-Hsp antibody concentrations. RESULTS: Our studies demonstrated that, when evaluated by ANOVA, patients with higher anti-Hsp (Hsp90, DnaK, and GroEL) antibody concentrations tended to have significantly (P< or =0.05) healthier periodontal tissues. This was most obvious when the relationship between mean probing depths and antibody concentrations were studied. For Hsp90 antibodies, 2 variables (probing depth and P. gingivalis concentration) were found to have significant contributions (R = 0.293, P<0.0002). The equation derived from the regression model was y = 12558-2070*PD +1842*PG. This confirmed the inverse relationship with probing depth and the positive relationship with colonization by P. gingivalis. Attempts to model the other stress protein antibodies were not successful. CONCLUSIONS: We believe that the present observations reflect the presence of protective anti-Hsp antibodies, rather than simply the presence of the microorganism in the gingival sulcus. The clinical significance of these observations lies in the potential of identifying patients who are at risk for developing periodontal disease based on their inability to mount an immune response to specific Hsp or Hsp epitopes, as well as the development of vaccines based on Hsp epitopes.

Spatial and temporal summation of sensory and affective dimensions of deep somatic pain.

There is considerable evidence in support of differential information processing of the sensory-discriminative and motivational-affective meanings of pain. The purpose of this work was to examine whether temporal (acute, tonic, persistent) and spatial (local, regional, widespread) aspects of deep somatic pain influence the sensory and affective dimensions of pain. Acute pain consisted of a short bout of pain, lasting about 100 s. Tonic pain was the experience of experimentally maintained pain for 18 min. Both acute and tonic pain were induced by infusion of an algesic or control substance into muscle with the subject blinded with respect to the type of infusion and randomization of the application sequence. Comparing the response of experimental subjects to a group of matched cases with persistent masticatory myalgia alone or in combination with widespread musculoskeletal pain, we examine whether the experimental state is different from the matched clinical condition, and whether there is a difference between the condition being restricted to the face or not. The McGill pain questionnaire was used to assess the sensory and affective correlates of pain. The normalized sensory score for acute/unilateral face pain was different from that established for tonic/unilateral face pain (P = 0.055, borderline s.), and so was the normalized affective score (P = 0.009, s.). When comparing tonic/unilateral versus tonic/bilateral face pain, the affective scores increased with increased pain involvement (P = 0.009, s.) while the sensory sores were unaffected by the additional pain induced in the contralateral masseter muscle (P = 0.357, n.s). Notably, sensory and affective scores for tonic/bilateral and persistent/bilateral face pain were not statistically different (sensory: P = 0.169, n.s.; affective: P = 0.643, n.s). On the other hand, when contrasting persistent/bilateral face pain with persistent/ widespread musculoskeletal pain, both scores were significantly different (sensory: P < 0.001, s.; affective: P = 0.041, s.). Time in and spread of pain influenced the perceptual correlates of pain to a significant degree. The major increase in the sensory dimension occurred from 'no pain' to 'acute pain'. Affective scores showed the most significant increases from acute to tonic pain, particularly with greater spatial involvement. The significant increases in sensory scores observed when contrasting persistent facial pain alone and in combination with widespread musculoskeletal pain was attributed to the broader body experience. Because the perceptual correlates of tonic and matched persistent (chronic) pain states were similar, we concluded that it does not require months for the development of the sensory and affective meaning of persistent pain as assumed.

Treatment-seeking patterns of facial pain patients: many possibilities, limited satisfaction.

Knowledge about the different kinds of treatment provided to patients with nonmalignant musculoskeletal facial pain is limited. The present study was based on 206 consecutive patients who were referred to a university-based tertiary care clinic for the diagnosis and management of persistent facial pain. Its purpose was to get information about the number and specialty of providers consulted by patients prior to their referral, and to follow the underlying treatment-seeking patterns. The results showed that on average 4.88 providers from 44 different categories were consulted. A general dentist or a dental specialist was seen by about 70% of patients. For patients whose first provider was a dentist, the most likely subsequent provider was another dentist. Conversely, if the first provider was a physician, chances were greater that the subsequent provider was a physician rather than a dentist. Among the nondental therapies patients received, physical therapy was chosen most frequently (42.2%). More than 60% of patients had at least one nondental treatment; however, the majority of these patients experienced two or more different types of such therapy (e.g., chiropractic, osteopathic, relaxation training). Patients' satisfaction with care and treatment was moderate, since only 18.5% of the patients were very satisfied, while 27.7% were dissatisfied or very dissatisfied. The present findings, which corroborate a recent study from the Kansas City, Missouri, region, indicate that patients with persistent facial pain see a large number of different providers, and that nonmedical/nondental treatment approaches are common. The moderate satisfaction experienced with any of the therapies points out that much needs to be done before this patient population is served satisfactorily.

Pain maps from facial pain patients indicate a broad pain geography.

Two hundred consecutive female patients, who were referred to a university-based facial pain clinic, were asked to mark all painful sites on sketches showing the contours of a human body in the frontal and rear views. The drawings were analyzed with transparent templates containing 1875 (frontal view) and 1929 (rear view) square cells of equal size. The average patient scored 71.8 cells in the frontal and 99.7 cells in the rear view (corresponding to 3.8% and 5.2% of the maximum possible scores). In individual patient drawings, however, up to 42.7% and 44.9% of all cells were marked. Only 37 cases (18.5%) exhibited pain that was limited to the trigeminal system. An analysis of the pain distribution according to the arrangements of dermatomes revealed three distinct clusters of patients: (1) pain restricted to the region innervated by the trigeminal nerves (n = 37); (2) pain in the trigeminal dermatomes and any combination involving the spinal dermatomes C2, C3, and C4, but no other dermatomes (n = 32); and (3) pain sites involving dermatomes in addition to the ones listed above (n = 131). Mean ages in the three clusters were 38.7, 35.5, and 37.5 years, respectively (p = 0.62, n.s.). Widespread pain existed for longer durations (median, 48 months) than conditions involving local and regional pain (median, 24 months) (p = 0.02, s.). Our findings showed that among a great percentage of persistent facial pain patients the pain distribution is more widespread than commonly assumed, and that the persistence of pain in the regional and widespread pain presentations is significantly greater than in cases with pain limited to the trigeminal system.

Analysis of cohort effects in mixed longitudinal data sets.

Mixed longitudinal designs are among the most efficient for the study of growth and developmental processes. In this approach, one studies several (birth) cohorts, each for a relatively short length of time, and then links the growth curves for the individual cohorts together to obtain the growth curve for the entire length of time spanned by the ages of the subjects in all cohorts. Thus, e.g., in the Nijmegen Growth Study, three cohorts were each studied for 5 years, the intent being to join the three curves together to form a single curve covering the entire period from 4 to 14 years of age. In order for this approach to be valid, there either should be no cohort effects (secular trends) or the fitted curve must be adjusted in some way to correct for such effects if they exist. The question thus arises as to how one should test for the presence of cohort effects and what one should do about them if found. The problems which may arise using height and weight data from the Nijmegen Growth Study are illustrated. In particular for girls, height and weight both show cohort effects (at 9.25 years of age) when the raw data are used. If, however, the observed data are used to estimate the values at the target age, and these values are used in the comparison, differences between the cohorts are no longer significant. The problems are further illustrated using data from a mixed longitudinal data set of cleft lip and palate patients and data from the National Dutch Growth Study 1980.

Greater disability with increased pain involvement, pain intensity and depressive preoccupation.

Persistent pain is often accompanied by functional disability. This study investigated the effect of pain extent and the involvement of specific pain sites on pain-related disability, as determined by the Pain Disability Index (PDI). Complete data were available from 278 persistent facial pain (PFP) patients. Patients were divided into one of two groups based on drawings of their pain distribution. When the patient's pain drawing was limited to the region supplied by the trigeminal nerves (Nn. V(1) V(2), and/or V(3)), with or without the inclusion of any combination of the cervical dermatomes C2, C3 and C4, the patient was assigned to the local/regional pain group. If the pain extended beyond this area, the patient was allocated to the group exhibiting widespread pain. In addition to the PDI, patients filled out the Beck Depression Inventory (BDI) and the State-Trait Anxiety Inventory (STAI). The local/regional pain group had significantly lower scores on the PDI, the BDI and STAI state than cases with widespread pain. Patients with widespread pain who indicated pain locations in any one or more of the extremities plus the lower back scored significantly higher on the PDI and the BDI than patients with no such combined involvement. Multiple regression analysis revealed that depressive preoccupation, pain extent and pain intensity were significant predictors of pain-related disability, whereas the STAI was not. If controlled for pain extent and pain intensity, the presence of high as opposed to low depressive scores added almost 11 points to the PDI score. These results showed that pain distribution, pain intensity and depressive mood are significant predictors of pain-related disability.

Pain descriptors characteristic of persistent facial pain.

The McGill Pain Questionnaire is an instrument that is widely used to assess the multidimensional experience of pain. Although it was introduced more than 20 years ago, limited information is available about its use in patients suffering from persistent facial pain. The aim of this study was to investigate the response patterns of persistent facial pain patients to the McGill Pain Questionnaire, to correlate these patterns with patients' beliefs about the seriousness of the condition, and to compare the findings with data reported from other painful conditions. The study sample consisted of 200 consecutive female patients referred to a tertiary care facial pain clinic. The Pain Rating Index scores of the McGill Pain Questionnaire subscales and the total number of words chosen by these patients closely matched the summary scores reported by Wilkie et al, who pooled data from seven pain conditions (cancer, chronic back, mixed chronic, acute/postoperative, labor/gynecological, dental, and experimentally induced) in their meta-analysis. On the other hand, when the data collected in this study were compared with those from specific clinical subsets, such as cancer patients, chronic back pain patients, or dental patients, differences in McGill Pain Questionnaire scores could be identified. Differences were also found in the choice of specific pain descriptors. More than 20% of the facial pain patients selected "radiating" and "pressing"; this was not the case for those suffering from other pain conditions. Facial pain patients who felt that their condition was more serious or different from what the treatment providers had told them had a greater likelihood of choosing specific word categories of the McGill Pain Questionnaire.

Temporomandibular disorders--pain outside the head and face is rarely acknowledged in the chief complaint.

STATEMENT OF PROBLEM: With diagnostic and therapeutic procedures being heavily influenced by the patient's chief complaint, the question arises whether this information alone represents a solid basis for clinical action. PURPOSE: The aim of this investigation was to assess the agreement between pain complaints and patient generated paper-and-pencil drawings of the distribution of pain in patients suffering from temporomandibular disorders. METHODS: The study included 140 adult female patients with temporomandibular disorders. Pain drawings served as a standard, against which the oral reports were compared. In 40 (29%) of the patients, pain was limited to the head and face; in the remaining subjects, it exceeded the boundaries of these regions. Nine potential pain sites were distinguished (head, face, neck, shoulders, arms, chest, abdomen, back, and legs). Whenever one of these regions was part of the drawing or the pain complaint, it was counted. Sensitivity, specificity, and kappa indices were computed for each site. RESULTS: Patients with pain limited to the head and face showed a close correspondence between pain report and drawing. On the other hand, patients with temporomandibular disorders with concomitant pain sites outside the head and face frequently did not mention these additional pain locations. This was reflected in low sensitivities (minimum: 0.00; maximum: 0.48) and low kappa values (minimum: -0.02; maximum: 0.19). CONCLUSIONS: This study showed that the chief complaint frequently underestimates the real extent of pain involvement.