Background and aims
In 2008, the International Association for the Study of Pain Special Interest Group on Neuropathic Pain (NeuPSIG) proposed a clinical grading system to help identify patients with neuropathic pain (NeP). We previously applied this classification system, along with two NeP screening tools, the painDETECT (PD-Q) and Leeds Assessment of Neuropathic Symptoms and Signs pain scale (LANSS), to identify NeP in patients with neck/upper limb pain. Both screening tools failed to identify a large proportion of patients with clinically classified NeP, however a limitation of our study was the use of a single clinician performing the NeP classification. In 2016, the NeuPSIG grading system was updated with the aim of improving its clinical utility. We were interested in field testing of the revised grading system, in particular in the application of the grading system and the agreement of interpretation of clinical findings. The primary aim of the current study was to explore the application of the NeuPSIG revised grading system based on patient records and to establish the inter-rater agreement of detecting NeP. A secondary aim was to investigate the level of agreement in detecting NeP between the revised NeuPSIG grading system and the LANSS and PD-Q.
Methods
In this retrospective study, two expert clinicians (Specialist Pain Medicine Physician and Advanced Scope Physiotherapist) independently reviewed 152 patient case notes and classified them according to the revised grading system. The consensus of the expert clinicians’ clinical classification was used as “gold standard” to determine the diagnostic accuracy of the two NeP screening tools.
Results
The two clinicians agreed in classifying 117 out of 152 patients (ICC 0.794, 95% CI 0.716–850; κ 0.62, 95% CI 0.50–0.73), yielding a 77% agreement. Compared to the clinicians’ consensus, both LANSS and PD-Q demonstrated limited diagnostic accuracy in detecting NeP (LANSS sensitivity 24%, specificity 97%; PD-Q sensitivity 53%, specificity 67%).
Conclusions
The application of the revised NeP grading system was feasible in our retrospective analysis of patients with neck/upper limb pain. High inter-rater percentage agreement was demonstrated. The hierarchical order of classification may lead to false negative classification. We propose that in the absence of sensory changes or diagnostic tests in patients with neck/upper limb pain, classification of NeP may be further improved using a cluster of clinical findings that confirm a relevant nerve lesion/disease, such as reflex and motor changes. The diagnostic accuracy of LANSS and PD-Q in identifying NeP in patients with neck/upper limb pain remains limited. Clinical judgment remains crucial to diagnosing NeP in the clinical practice.
Implications
Our observations suggest that in view of the heterogeneity in patients with neck/upper limb pain, a considerable amount of expertise is required to interpret the revised grading system. While the application was feasible in our clinical setting, it is unclear if this will be feasible to apply in primary health care settings where early recognition and timely intervention is often most needed. The use of LANSS and PD-Q in the identification of NeP in patients with neck/upper limb pain remains questionable.
Entrapment neuropathies such as carpal tunnel syndrome, radiculopathies, or radicular pain are the most common peripheral neuropathies and also the most common cause for neuropathic pain. Despite their high prevalence, they often remain challenging to diagnose and manage in a clinical setting. Summarising the evidence from both preclinical and clinical studies, this review provides an update on the aetiology and pathophysiology of entrapment neuropathies. Potential mechanisms are put in perspective with clinical findings. The contemporary assessment is discussed and diagnostic pitfalls highlighted. The evidence for the noninvasive and surgical management of common entrapment neuropathies is summarised and future areas of research are identified.
Entrapment neuropathies are a heterogenous condition reflecting distinct underlying pathomechanisms. A contemporary assessment aimed at identifying potential mechanisms may help target management for these patients.
Nervenkompressionssyndrome („Engpass-Syndrome“) wie Karpaltunnelsyndrom, Radikulopathien oder radikulärer Schmerz sind die häufigsten peripheren Nervenläsionen und auch die häufigste Ursache für neuropathischen Schmerz. Trotz ihrer hohen Prävalenz stellen sie diagnostisch und therapeutisch weiterhin oft eine klinische Herausforderung dar. Die vorliegende Übersicht bietet aktuelle Informationen zur Ätiologie und Pathophysiologie von Nervenkompressionssyndromen; dafür wird die Evidenz aus präklinischen wie auch klinischen Studien zusammengefasst. Mögliche Mechanismen werden in den Kontext klinischer Befunde gestellt. Das aktuelle diagnostische Vorgehen wird erörtert, diagnostische Fallstricke werden beleuchtet. Zuletzt fasst der Beitrag die Evidenz für die nichtinvasive und chirurgische Therapie häufiger Nervenkompressionssyndrome zusammen und zeigt zukünftige Forschungsbereiche auf.
Wir kennen neurodynamische Tests und Behandlungsmethoden, nutzen diese alltäglich in der Praxis und gehen auf Kurse, um mehr darüber zu lernen. Aber was verstehen wir tatsächlich darunter? Kommen wir in unserem Verständnis darüber auf einen gemeinsamen Nenner? Dieser Artikel gibt einen Einblick in die Thematik Neurodynamik. Bisherige Überzeugungen stehen dabei auf dem Prüfstand.
Nervenschmerz ist nicht gleich Nervenschmerz. Um Patienten mit ausstrahlenden Schmerzen, bei denen die Nerven eine Rolle spielen könnten, adäquat zu therapieren, sind eine gründliche Untersuchung und ein fundiertes Clinical Reasoning unerlässlich. Nur dadurch entpuppen sich die beiden Patientinnen mit fast identischen Symptomen als sehr unterschiedlich.
Background: The painDETECT questionnaire (PD-Q) has been used as a tool to characterize sensory abnormalities in patients with persistent pain. This study investigated whether the self-reported sensory descriptors of patients with painful cervical radiculopathy (CxRAD) and patients with fibromyalgia (FM), as characterized by responses to verbal sensory descriptors from PD-Q (sensitivity to light touch, cold, heat, slight pressure, feeling of numbness in the main area of pain), were associated with the corresponding sensory parameters as demonstrated by quantitative sensory testing (QST).
Methods: Twenty-three patients with CxRAD (eight women, 46.3 ± 9.6 years) and 22 patients with FM (20 women, 46.1 ± 11.5 years) completed the PD-Q. Standardized QST of dynamic mechanical allodynia, cold and heat pain thresholds, pressure pain thresholds, mechanical and vibration detection thresholds, was recorded from the maximal pain area. Comparative QST data from 31 age-matched healthy controls (HCs; 15 women) were obtained.
Results: Patients with CxRAD demonstrated a match between their self-reported descriptors and QST parameters for all sensory parameters except for sensitivity to light touch, and these matches were statistically significant compared with HC data (p ≤ 0.006). The FM group demonstrated discrepancies between the PD-Q and QST sensory phenotypes for all sensory descriptors, indicating that the self-reported sensory descriptors did not consistently match the QST parameters (p = ≤0.017).
Conclusion: Clinicians and researchers should be cautious about relying on PD-Q as a stand-alone screening tool to determine sensory abnormalities in patients with FM.
Identification of differences in clinical presentation and underlying pain mechanisms may assist the classification of patients with neck–arm pain which is important for the provision of targeted best evidence based management. The aim of this study was to: (i) assess the inter-examiner agreement in using specific systems to classify patients with cervical radiculopathy and patients with non-specific neck–arm pain associated with heightened nerve mechanosensitivity (NSNAP); (ii) assess the agreement between two clinical examiners and two clinical experts in classifying these patients, and (iii) assess the diagnostic accuracy of the two clinical examiners. Forty patients with unilateral neck–arm pain were examined by two clinicians and classified into (i) cervical radiculopathy, (ii) NSNAP, (iii) other. The classifications were compared to those made independently by two experts, based on a review of patients' clinical assessment notes. The experts' opinion was used as the reference criterion to assess the diagnostic accuracy of the clinical examiners in classifying each patient group. There was an 80% agreement between clinical examiners, and between experts and 70%–80% between clinical examiners and experts in classifying patients with cervical radiculopathy (kappa between 0.41 and 0.61). Agreement was 72.5%–80% in classifying patients with NSNAP (kappa between 0.43 and 0.52). Clinical examiners' diagnostic accuracy was high (radiculopathy: sensitivity 79%–84%; specificity 76%–81%; NSNAP: sensitivity 78%–100%; specificity 71%–81%). Compared to expert opinion, clinicians were able to identify patients with cervical radiculopathy and patients with NSNAP in 80% of cases, our data supporting the reliability of these classification systems.
Neuropathischer Schmerz
(2014)
Neuropathische Schmerzen entstehen durch eine Läsion oder Erkrankung des somatosensorischen Nervensystems. Davon sind ca. 7 – 8 % der Normalbevölkerung betroffen. Patienten mit neuropathischen Schmerzen leiden unter erheblichen Einschränkungen ihrer Lebensqualität und die daraus resultierenden staatlichen Gesundheitskosten sind extrem hoch.
Die frühe Identifikation vorhandener neuropathischer Schmerzen ist ausschlaggebend für eine gezielte Schmerztherapie und Vorbeugung einer Chronifizierung des Krankheitszustandes. Das klinische Bild ist vielfältig, und die Diagnostik kann in der klinischen Praxis eine Herausforderung darstellen.
Der Schwerpunkt dieses Artikels liegt in der Untersuchung und Diagnosestellung neuropathischer Schmerzen.
Background/Aim
This study aimed to establish the somatosensory profile of patients with lumbar radiculopathy at pre-and post-microdiscectomy and to explore any association between pre-surgical quantitative sensory test (QST) parameters and post-surgical clinical outcomes.
Methods
A standardized QST protocol was performed in 53 patients (mean age 38 ± 11 years, 26 females) with unilateral L5/S1 radiculopathy in the main pain area (MPA), affected dermatome and contralateral mirror sites and in age- and gender-,and body site-matched healthy controls. Repeat measures at 3 months included QST, the Oswestry Disability Index (ODI) and numerous other clinical measures; at 12 months, only clinical measures were repeated. A change <30% on the ODI was defined as ‘no clinically meaningful improvement’.
Results
Patients showed a significant loss of function in their symptomatic leg both in the dermatome (thermal, mechanical, vibration detection p < .002), and MPA (thermal, mechanical, vibration detection, mechanical pain threshold, mechanical pain sensitivity p < .041) and increased cold sensitivity in the MPA (p < .001). Pre-surgical altered QST parameters improved significantly post-surgery in the dermatome (p < .018) in the symptomatic leg and in the MPA (p < .010), except for thermal detection thresholds and cold sensitivity. Clinical outcomes improved at 3 and 12 months (p < .001). Seven patients demonstrated <30% change on the ODI at 12 months. Baseline loss of function in mechanical detection in the MPA was associated with <30% change on the ODI at 12 months (OR 2.63, 95% CI 1.09–6.37, p = .032).
Conclusion
Microdiscectomy resulted in improvements in affected somatosensory parameters and clinical outcomes. Pre-surgical mechanical detection thresholds may be predictive of clinical outcome.
Significance
This study documented quantitative sensory testing (QST) profiles in patients with lumbar radiculopathy in their main pain area (MPA) and dermatome pre- and post-microdiscectomy and explored associations between QST parameters and clinical outcome. Lumbar radiculopathy was associated with loss of function in modalities mediated by large and small sensory fibres. Microdiscectomy resulted in significant improvements in loss of function and clinical outcomes in 85% of our cohort. Pre-surgical mechanical detection thresholds in the MPA may be predictive of clinical outcome.
Abstract
Background
The clinical presentation of neck-arm pain is heterogeneous with varying underlying pain types (nociceptive/neuropathic/mixed) and pain mechanisms (peripheral/central sensitization). A mechanism-based clinical framework for spinally referred pain has been proposed, which classifies into (1) somatic pain, (2) neural mechanosensitivity, (3) radicular pain, (4) radiculopathy and mixed pain presentations. This study aims to (i) investigate the application of the clinical framework in patients with neck-arm pain, (ii) determine their somatosensory, clinical and psychosocial profile and (iii) observe their clinical course over time.
Method
We describe a study protocol. Patients with unilateral neck-arm pain (n = 180) will undergo a clinical examination, after which they will be classified into subgroups according to the proposed clinical framework. Standardized quantitative sensory testing (QST) measurements will be taken in their main pain area and contralateral side. Participants will have to complete questionnaires to assess function (Neck Disability Index), psychosocial factors (Tampa Scale of Kinesiophobia, Pain Catastrophizing Scale, Depression, anxiety and stress scale), neuropathic pain (Douleur Neuropathique 4 Questions, PainDETECT Questionnaire) and central sensitization features (Central Sensitization Inventory). Follow-ups at three, six and 12 months include the baseline questionnaires. The differences of QST data and questionnaire outcomes between and within groups will be analyzed using (M)AN(C)OVA and/or regression models. Repeated measurement analysis of variance or a linear mixed model will be used to calculate the differences between three, six, and 12 months outcomes. Multiple regression models will be used to analyze potential predictors for the clinical course.
Conclusion
The rationale for this study is to assess the usability and utility of the proposed clinical framework as well as to identify possible differing somatosensory and psychosocial phenotypes between the subgroups. This could increase our knowledge of the underlying pain mechanisms. The longitudinal analysis may help to assess possible predictors for pain persistency.