Summary The goals of an international taskforce on somatosensory testing established by the Special Interest Group of Oro‐facial Pain (SIG‐OFP) under the International Association for the Study of ...Pain (IASP) were to (i) review the literature concerning assessment of somatosensory function in the oro‐facial region in terms of techniques and test performance, (ii) provide guidelines for comprehensive and screening examination procedures, and (iii) give recommendations for future development of somatosensory testing specifically in the oro‐facial region. Numerous qualitative and quantitative psychophysical techniques have been proposed and used in the description of oro‐facial somatosensory function. The selection of technique includes time considerations because the most reliable and accurate methods require multiple repetitions of stimuli. Multiple‐stimulus modalities (mechanical, thermal, electrical, chemical) have been applied to study oro‐facial somatosensory function. A battery of different test stimuli is needed to obtain comprehensive information about the functional integrity of the various types of afferent nerve fibres. Based on the available literature, the German Neuropathic Pain Network test battery appears suitable for the study of somatosensory function within the oro‐facial area as it is based on a wide variety of both qualitative and quantitative assessments of all cutaneous somatosensory modalities. Furthermore, these protocols have been thoroughly described and tested on multiple sites including the facial skin and intra‐oral mucosa. Standardisation of both comprehensive and screening examination techniques is likely to improve the diagnostic accuracy and facilitate the understanding of neural mechanisms and somatosensory changes in different oro‐facial pain conditions and may help to guide management.
Brining and dry salting are traditional preservation techniques used to extend the shelf life of foods including seaweeds. In this study, brining (40% NaCl solution weight/volume) and dry salting ...(30% weight/weight) processes were applied to fresh kelp to achieve a target water activity of less than 0.77, and the effect of salting treatment on consumer acceptance was assessed. The processed samples were stored at 4 °C for 2 weeks until the sensory analysis. Processed kelp samples were used as the primary ingredient in a salad with shredded carrots and sesame dressing. Three salad samples (salad with fresh kelp (control), brined, or dry salted sugar kelp) were presented to the panelists to assess the liking of sensory attributes including salt intensity, color, aroma, flavor, texture, and overall liking. Significant differences in the liking of flavor and texture were observed, with consumers rating both treatments made with salted seaweed higher than a salad made from fresh seaweed. Panelists identified the availability and lack of information regarding nutritional benefits as barriers to their seaweed consumption. These results indicate that in addition to extending shelf life, the preservation of kelp by salting may increase consumer acceptability.
Quantitative sensory tests (QSTs) have been increasingly used to investigate alterations in somatosensory function in a wide range of painful conditions. The interpretation of these findings is based ...on the assumption that the measures are stable and reproducible. To date, reliability of QST has been investigated for short test-retest intervals. The aim of this study was to investigate the long-term reliability of a multimodal QST assessment in healthy people, with testing conducted on 3 occasions over 4 months. Forty-two healthy people were enrolled in the study. Static and dynamic tests were performed, including cold and heat pain threshold (CPT, HPT), mechanical wind-up wind-up ratio (WUR), pressure pain threshold (PPT), 2-point discrimination (TPD), and conditioned pain modulation (CPM). Systematic bias, relative reliability and agreement were analysed using repeated measure analysis of variance, intraclass correlation coefficients (ICCs3,1) and SE of the measurement (SEM), respectively. Static QST (CPT, HPT, PPT, and TPD) showed good-to-excellent reliability (ICCs: 0.68-0.90). Dynamic QST (WUR and CPM) showed poor-to-good reliability (ICCs: 0.35-0.61). A significant linear decrease over time was observed for mechanical QST at the back (PPT and TPD) and for CPM (P < 0.01). Static QST were stable over a period of 4 months; however, a small systematic decrease over time has been observed for mechanical QST. Dynamic QST showed considerable variability over time; in particular, CPM using PPT as the test stimulus did not show adequate reliability, suggesting that this test paradigm may be less useful for monitoring individuals over time.
Classification of musculoskeletal pain based on underlying pain mechanisms (nociceptive, neuropathic, and nociplastic pain) is challenging. In the absence of a gold standard, verification of features ...that could aid in discrimination between these mechanisms in clinical practice and research depends on expert consensus. This Delphi expert consensus study aimed to: (1) identify features and assessment findings that are unique to a pain mechanism category or shared between no more than 2 categories and (2) develop a ranked list of candidate features that could potentially discriminate between pain mechanisms. A group of international experts were recruited based on their expertise in the field of pain. The Delphi process involved 2 rounds: round 1 assessed expert opinion on features that are unique to a pain mechanism category or shared between 2 (based on a 40% agreement threshold); and round 2 reviewed features that failed to reach consensus, evaluated additional features, and considered wording changes. Forty-nine international experts representing a wide range of disciplines participated. Consensus was reached for 196 of 292 features presented to the panel (clinical examination-134 features, quantitative sensory testing-34, imaging and diagnostic testing-14, and pain-type questionnaires-14). From the 196 features, consensus was reached for 76 features as unique to nociceptive (17), neuropathic (37), or nociplastic (22) pain mechanisms and 120 features as shared between pairs of pain mechanism categories (78 for neuropathic and nociplastic pain). This consensus study generated a list of potential candidate features that are likely to aid in discrimination between types of musculoskeletal pain.
AIM: This critical review describes key methodological aspects for a successful orofacial psychophysical evaluation of the somatosensory system and highlights the diagnostic value of somatosensory ...assessment and management perspectives based on somatosensory profiling.
METHODS: This topical review was based on a non-systematic search for studies about somatosensory evaluation in orofacial pain in PubMed and Embase.
RESULTS: The recent progress regarding psychophysical evaluation of somatosensory function was largely possible due to the development and application of valid, reliable, and standardized psychophysical methods. Qualitative sensory testing may be useful as a screening tool to rule out relevant somatosensory abnormalities. Nevertheless, the patient should preferably be referred to a more comprehensive assessment with the quantitative sensory testing battery if confirmation of somatosensory abnormalities is necessary. Moreover, the identification of relevant somatosensory alterations in chronic pain disorders that do not fulfill the current criteria to be regarded as neuropathic has also increased the usefulness of somatosensory evaluation as a feasible method to better characterize the patients and perhaps elucidate some underpinnings of the so-called "nociplastic" pain disorders. Finally, an additional benefit of orofacial pain treatment based on somatosensory profiling still needs to be demonstrated and convincing evidence of somatosensory findings as predictors of treatment efficacy in chronic orofacial pain awaits further studies.
CONCLUSION: Psychophysical evaluation of somatosensory function in orofacial pain is still in its infancy but with a clear potential to continue to improve the assessment, diagnosis and management of orofacial pain patients.
The study aimed to evaluate the applicability and repeatability of cold stimulation in dogs.
10 healthy Beagle dogs were used in a blinded cross-over experiment.
Measurements were performed in ...triplicate at 4 skin locations. The probe was manually placed, and temperature decreased (32 to 10 °C) at different cooling rates (0.5, 1, and 5 °C second-1) and latency was measured (11 °C for 60 seconds). Stimulations were discontinued when avoidance reactions were detected. Thermal threshold or time-to-reaction were recorded. Experiments were performed 3 times per animal in weeks 1 (Exp1), 2 (Exp2), and 5 (Exp3). Feasibility of cold stimulation was scored (0-5). Data were analyzed with mixed logistic regression.
No significant differences in number of avoidance reactions between cooling-rates were detected. Significantly more reactions (P < .001) were observed during Exp1 compared to Exp2 and Exp3. Thermal thresholds were 13 ± 2.6 °C, 17.7 ± 4 °C and 16.3 ± 4.6 °C for 5, 0.5 and 1 °C second-1, respectively. Latency to the reaction was determinable in 37% of measurements. The mean time-to-reaction was 13 ± 11 seconds. In 85% of measurements, a feasibility score of 0 (best feasibility) was assigned.
The method is easily applicable and well tolerated, but habituation could not be excluded. Overall, the aversiveness of cold stimulation in healthy dogs is limited and it is not possible to recommend a specific protocol. In future studies, it needs to be determined if the aversiveness of cold stimulation is increased in diseased dogs.
Pain prevention and management is one of the primary goals of dental care. Postoperative dental pain (PDP) following caries removal and performance of a restorative dental treatment is a common ...clinical phenomenon, often causing significant discomfort to dental patients. In the present study, a psychophysical non-invasive method, qualitative sensory testing (QualST), was used in an attempt to foretell PDP following dental restorative procedures. Forty-two dental patients underwent an intra-oral cold QualST four times: immediately prior to a restorative dental procedure and at a follow-up meeting 1−3 weeks later, on the treated and on the contralateral oral sides. The QualST measures included subjects’ evaluation of the magnitude of pain and cold sensations experienced (on visual analogue scales) and the duration of the cold sensation (in seconds). Additional measures included age, gender, level of dental anxiety, jaw treated, and type of dental restoration performed (Class I or Class V). Subjects’ PDP was assessed through the phone using numeric rating scales 24, 48, and 72 h postoperatively. The highest level of PDP experienced by subjects occurred 24 h postoperatively (ANOVA with repeated measures). Of the study variables, the QualST pain sensation (B = 0.645, p < 0.001), duration of the cold sensation (B = 0.042, p < 0.05), and an interaction between gender and dental anxiety (B = 0.136, p < 0.05) emerged as possible predictors of the highest PDP experienced by subjects (stepwise regression). The results suggest that subjects’ reaction to an intra-oral cold stimulation of the oral mucosa can serve as a potential tool to foretell postoperative dental pain following restorative dental procedures.
Stratification of patients according to the individual sensory phenotype has been suggested a promising method to identify responders for pain treatment. However, many state-of-the-art sensory ...testing procedures are expensive or time-consuming.
Therefore, this study aimed to present a selection of easy-to-use bedside devices.
In total, 73 patients (39 m/34 f) and 20 controls (11 m/9 f) received a standardized laboratory quantitative sensory testing (QST) and a bedside-QST. In addition, 50 patients were tested by a group of nonexperienced investigators to address the impact of training. The sensitivity, specificity, and receiver-operating characteristics were analyzed for each bedside-QST parameter as compared to laboratory QST. Furthermore, the patients' individual sensory phenotype (ie, cluster) was determined using laboratory QST, to select bedside-QST parameters most indicative for a correct cluster allocation.
The bedside-QST parameters "loss of cold perception to 22°C metal," "hypersensitivity towards 45°C metal," "loss of tactile perception to Q-tip and 0.7 mm CMS hair," as well as "the allodynia sum score" indicated good sensitivity and specificity (ie,
70%). Results of interrater variability indicated that training is necessary for individual parameters (ie, CMS 0.7). For the cluster assessment, the respective bedside quantitative sensory testing (QST) parameter combination indicated the following agreements as compared to laboratory QST stratification: excellent for "sensory loss" (area under the curve AUC = 0.91), good for "thermal hyperalgesia" (AUC = 0.83), and fair for "mechanical hyperalgesia" (AUC = 0.75).
This study presents a selection of bedside parameters to identify the individual sensory phenotype as cost and time efficient as possible.
Thumb carpometacarpal osteoarthritis (CMC1 OA) is a prevalent and debilitating condition that lacks effective treatments. Understanding the multidimensional pain experience across CMC1 OA disease ...stages is crucial to improving treatment outcomes. This study examined how radiographic CMC1 OA severity is associated with physical, psychological, and somatosensory function.
Thirty-one women with early-stage (Eaton-Littler 1–2) or end-stage (Eaton-Littler 3–4) radiographic CMC1 OA completed validated questionnaires to assess pain, disability, and psychological function. Additionally, experimental pain was measured in each participant using quantitative sensory testing (QST) (mechanical, pressure, vibratory, thermal) at seven body sites (thenar, hypothenar, brachioradialis bi-laterally; quadriceps on affected side). Cohort differences (early-vs. end-stage) across all variables were analyzed using a multivariable modeling approach that included fixed effects and interactions; notably, age was controlled as a confounder.
End-stage CMC1 OA participants had higher scores in the pain (p = 0.01) and function (p = 0.02) portions of the AUSCAN assessment, self-reported disability of the DASH questionnaire (p = 0.04), and painDETECT scores (p = 0.03), indicating greater pain and disability compared to early-stage participants. Additionally, end-stage CMC1 OA participants demonstrated reduced vibratory detection and heat pain thresholds at multiple body sites (p's < 0.05), with significant interactions observed across the mechanical and cold stimuli.
Findings revealed women with end-stage CMC1 OA exhibited increased neuropathic pain characteristics and somatosensory loss compared to those with early-stage CMC1 OA. These results underscore the importance of addressing both peripheral and centralized pain mechanisms and the need for multimodal approaches in the treatment of CMC1 OA.
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