B. Tampin

Quantitative sensory testing somatosensory profiles in patients with cervical radiculopathy are distinct from those in patients with nonspecific neck-arm pain

Summary Patients with cervical radiculopathy and patients with nonspecific neck–arm pain demonstrated distinctive somatosensory profiles, potentially reflecting differences in underlying pathophysiology and pain mechanisms. ABSTRACT The aim of this study was to establish the somatosensory profiles of patients with cervical radiculopathy and patients with nonspecific neck–arm pain associated with heightened nerve mechanosensitivity (NSNAP). Sensory profiles were compared to healthy control (HC) subjects and a positive control group comprising patients with fibromyalgia (FM). Quantitative sensory testing (QST) of thermal and mechanical detection and pain thresholds, pain sensitivity and responsiveness to repetitive noxious mechanical stimulation was performed in the maximal pain area, the corresponding dermatome and foot of 23 patients with painful C6 or C7 cervical radiculopathy, 8 patients with NSNAP in a C6/7 dermatomal pain distribution, 31 HC and 22 patients with FM. For both neck–arm pain groups, all QST parameters were within the 95% confidence interval of HC data. Patients with cervical radiculopathy were characterised by localised loss of function (thermal, mechanical, vibration detection P < .009) in the maximal pain area and dermatome (thermal detection, vibration detection, pressure pain sensitivity P < .04), consistent with peripheral neuronal damage. Both neck–arm pain groups demonstrated increased cold sensitivity in their maximal pain area (P < .03) and the foot (P < .009), and this was also the dominant sensory characteristic in patients with NSNAP. Both neck–arm pain groups differed from patients with FM, the latter characterised by a widespread gain of function in most nociceptive parameters (thermal, pressure, mechanical pain sensitivity P < .027). Despite commonalities in pain characteristics between the 2 neck–arm pain groups, distinct sensory profiles were demonstrated for each group.

Identification of neuropathic pain in patients with neck/upper limb pain: Application of a grading system and screening tools

Summary The NeuPSIG grading system was feasible for identification of neuropathic pain in patients with neck/upper limb pain. LANSS and painDETECT diagnostic accuracy was limited. Abstract The Neuropathic Pain Special Interest Group (NeuPSIG) of the International Association for the Study of Pain has proposed a grading system for the presence of neuropathic pain (NeP) using the following categories: no NeP, possible, probable, or definite NeP. To further evaluate this system, we investigated patients with neck/upper limb pain with a suspected nerve lesion, to explore: (i) the clinical application of this grading system; (ii) the suitability of 2 NeP questionnaires (Leeds Assessment of Neuropathic Symptoms and Signs pain scale [LANSS] and the painDETECT questionnaire [PD‐Q]) in identifying NeP in this patient cohort; and (iii) the level of agreement in identifying NeP between the NeuPSIG classification system and 2 NeP questionnaires. Patients (n = 152; age 52 ± 12 years; 53% male) completed the PD‐Q and LANSS questionnaire and underwent a comprehensive clinical examination. The NeuPSIG grading system proved feasible for application in this patient cohort, although it required considerable time and expertise. Both questionnaires failed to identify a large number of patients with clinically classified definite NeP (LANSS sensitivity 22%, specificity 88%; PD‐Q sensitivity 64%, specificity 62%). These lowered sensitivity scores contrast with those from the original PD‐Q and LANSS validation studies and may reflect differences in the clinical characteristics of the study populations. The diagnostic accuracy of LANSS and PD‐Q for the identification of NeP in patients with neck/upper limb pain appears limited.

Neuropathic Pain Components Are Common in Patients With Painful Cervical Radiculopathy, but Not in Patients With Nonspecific Neck-Arm Pain

Objectives:The aim of this study was to investigate, using quantitative sensory testing (QST) parameters and the painDETECT (PD-Q) screening questionnaire, the presence of neuropathic pain (NeP) in patients with unilateral painful cervical radiculopathy (CxRAD) and in patients with unilateral nonspecific neck-arm pain associated with heightened nerve mechanosensitivity (NSNAP). Methods:All patients completed the PD-Q before QST. QST was performed bilaterally in the maximal pain area and the affected dermatome in 23 patients with painful C6 or C7 radiculopathy and in 8 patients with NSNAP following a C6/7 dermatomal pain distribution. Results:Patients with CxRAD demonstrated a significant loss of sensory function in mechanical (P⩽0.021) and vibration sense (P⩽0.003) on the symptomatic side compared with the asymptomatic side in both tested body regions and in the dermatome reduced cold detection (P=0.021) and pressure pain sensitivity (P=0.005), findings consistent with nerve root damage. These sensory alterations in the maximal pain area/symptomatic side are confirmative for the presence of NeP. In contrast to these QST data, only 30% of patients with CxRAD demonstrated a NeP component according to the PD-Q score. In patients with NSNAP, a significant side-to-side difference was demonstrated for warm detection threshold in the dermatome (P=0.030). The PD-Q score indicated that NeP components were unlikely in this group. Discussion:QST data suggest that NeP is likely to be observed in patients with painful CxRAD, but not in patients with NSNAP.

Self-reported sensory descriptors are associated with quantitative sensory testing parameters in patients with cervical radiculopathy, but not in patients with fibromyalgia

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).

Entrapment Neuropathies: Challenging Common Beliefs With Novel Evidence

Entrapment neuropathies are the most prevalent type of peripheral neuropathy and often a challenge to diagnose and treat. To a large extent, our current knowledge is based on empirical concepts and early (often biomechanical) studies. This Viewpoint will challenge some of the current beliefs with recent advances in both basic and clinical neurosciences. J Orthop Sports Phys Ther 2018;48(2):58-62. doi:10.2519/jospt.2018.0603.

Reliability of the English version of the painDETECT questionnaire

Abstract Background: The painDETECT questionnaire (PD-Q) has been used widely for the identification of neuropathic pain (NeP); however, the reliability of the English version of the PD-Q has never been investigated. Objective: This study aimed to determine the reliability of the PD-Q pre- (T0) and immediately post- (T1) clinical consultation and at one-week follow-up (T2). Methods: We recruited 157 patients attending a Neurosurgery Spinal Clinic and Pain Management Department. Minor changes to PD-Q instructions were made to facilitate patient understanding; however, no changes to individual items or scoring were made. Intraclass correlation coefficients (ICCs) were used to assess the reliability of PD-Q total scores between T0–T1 and T0–T2; weighted kappa (κ) was used to assess the agreement of PD-Q classifications (unlikely NeP, ambiguous, likely NeP) between all time-points. To ensure stability of clinical pain, patients scoring ≤2 or ≥6 on the Patient Global Impression Scale (PGIC) at T2 were excluded from the T0–T2 analysis. Results: Accounting for missing data and exclusions (change in PGIC score), data for 136 individuals (mean [SD] age: 56.8 [15.2]; 54% male) was available, of whom n = 129 were included in the T0–T1 and n = 69 in the T0–T2 comparisons. There was almost perfect agreement between the PD-Q total scores at T0–T1 time-points (ICC 0.911; 95% CI: 0.882–0.941) and substantial agreement at T0–T2 (ICC 0.792; 95% CI: 0.703–0.880). PD-Q classifications demonstrated substantial agreement for T0–T1 (weighted κ: 0.771; 95% CI: 0.683–0.858) and for T0–T2 (weighted κ: 0.691; 95% CI: 0.553–0.830). Missing data was accounted in 13% of our cohort and over 42% of our patients drew multiple pain areas on the PD-Q body chart. Conclusion: The English version of the PD-Q is reliable as a screening tool for NeP. The validity of the questionnaire is still in question and has to be investigated in future studies.

The prevalence of back pain in patients in one Australian tertiary hospital population

OBJECTIVES The aims of the present study were to provide back pain (BP) point prevalence data from inpatients at an Australian tertiary hospital on one day, and compare this with Australian non-hospitalized population prevalence data; to collect data around the development of BP throughout hospital admission; and to analyse the association between BP and past history of BP, gender, age, admission specialty and hospital length of stay (LOS). METHODS This was a single-site, prospective, observational study of hospitalized inpatients on one day during 2016, with a subsequent survey over the following 11 days (unless discharge or death occurred sooner). RESULTS Data were collected from 343 patients (75% of the hospitalized cohort). A third of patients (n = 108) reported BP on admission, and almost a fifth (n = 63) developed new BP during their hospitalization. Patients who described BP at any time during their hospital stay had a higher chance of having had a history of BP, with odds increasing after adjustment for age and gender (odds ratio 5.89; 95% confidence interval (CI) 3.0 to 11.6; p < 0.001). After adjusting for age and gender, those experiencing BP had a significantly longer LOS (median 13 days; CI 10.8 to 15.3) than those who did not (median 10 days; CI 8.4 to 11.6; p = 0.034). CONCLUSIONS Hospital LOS for patients who complained of BP at any time during their admission was 3 days longer than those who had no BP, and a history of BP predicted a higher likelihood of BP during admission. Screening of patients on admission to identify any history of BP, and application of a package of care including early mobilization and analgesia may prevent the onset of BP and reduce LOS.

Sensory profiles are comparable in patients with distal and proximal entrapment neuropathies, while the pain experience differs.

Abstract Objective: Distal and proximal entrapment neuropathies such as carpal tunnel syndrome (CTS) and cervical radiculopathy (CR) share similar etiologies. Experimental models suggest that, despite comparable etiology, pathomechanisms associated with injuries of the peripheral and central axon branches are distinct. This study therefore compared self-reported and elicited sensory profiles in patients with distal and proximal entrapment neuropathies. Methods: Patients with electrodiagnostically confirmed CTS (n = 103) and patients with CR (n = 23) were included in this study. A group of healthy participants served as controls (n = 39). Symptoms and sensory profiles were evaluated using quantitative sensory testing (QST) and a self-reported neuropathic pain questionnaire (painDETECT). Results: Both patient groups were characterized by a loss of function in thermal and mechanical detection in the main pain area and dermatome compared to healthy reference data (p < .001). There was no significant difference between patients with CTS and CR in pain and detection thresholds except for reduced vibration sense in the main pain area (p < .001) and reduced pressure pain sensitivity in the dermatome in patients with CR (p < .001). However, patients with CR reported higher pain intensities (p = .008), more severe pain attacks (p = .009) and evoked pain by light pressure (p = .002) compared to patients with CTS. Conclusion: While QST profiles were similar between patients with CTS and CR, self-reported pain profiles differed and may suggest distinct underlying mechanisms in these patient cohorts.

Characterisation of pain in people with hereditary neuropathy with liability to pressure palsy

Hereditary neuropathy with liability to pressure palsy (HNPP) has historically been considered a pain-free condition, though some people with HNPP also complain of pain. This study characterised persistent pain in people with HNPP. Participants provided cross-sectional demographic data, information on the presence of neurological and persistent pain symptoms, and the degree to which these interfered with daily life. The painDETECT and Central Sensitization Inventory questionnaires were used to indicate potential neuropathic, central sensitisation and musculoskeletal (nociceptive) pain mechanisms. Additionally, participants were asked if they thought that pain was related to/part of HNPP. 32/43 (74%) subjects with HNPP had persistent pain and experience this pain in the last week. Of those with pain, 24 (75%) were likely to have neuropathic pain and 27 (84%) were likely to have central sensitisation. All 32 participants felt that their pain could be related to/part of their HNPP. Significant negative impact of the pain was common. Pain characterisation identified neuropathic pain and/or central sensitisation as common, potential underlying processes. Pain may plausibly be directly related to the underlying pathophysiology of HNPP. Further consideration of including pain as a primary symptom of HNPP is warranted.

128 COMPARISON OF LEVEL OF AGREEMENT BETWEEN TWO NEUROPATHIC PAIN QUESTIONNAIRES IN TWO DIFFERENT PATIENT POPULATIONS

Results: There was an average 68% and 66% improvement in pain and ODI, respectively, between pre-treatment and 24 months (p < 0.0001 for both comparisons). The maximum score of 5 on the Prolo scale was achieved in 63% and 22% of patients for economic and functional status, respectively. The global clinical success rate was 78% (39 of 50) based on no reoperations at the affected level due to persistent symptoms, a ≥2-point improvement in pain severity and a ≥15-point improvement in the ODI. Predictors of 24 month clinical success included discographic concordance (p < 0.0001), HIZ (p =0.0003), Pfirrmann grade (p =0.0002), and percent annulus coverage (p < 0.0001). There were no procedurerelated adverse events. Conclusions: The findings of this study suggest that durable clinical improvements can be realized after IDET in highly selected patients with mild disc degeneration, confirmatory imaging evidence of annular disruption and highly concordant pain provocation by low pressure discography.