Clinical indicators to identify neuropathic pain in low back related leg pain: a modified Delphi study

BACKGROUND

Neuropathic pain (NP) is common in patients presenting with low back related leg pain. Accurate diagnosis of NP is fundamental to ensure appropriate intervention. In the absence of a clear gold standard, expert opinion provides a useful methodology to progress research and clinical practice. The aim of this study was to achieve expert consensus on a list of clinical indicators to identify NP in low back related leg pain.

METHODS

A modified Delphi method consisting of three rounds was designed in accordance with the Conducting and Reporting Delphi Studies recommendations. Recruitment involved contacting experts directly and through expressions of interest on social media. Experts were identified using pre-defined eligibility criteria. Priori consensus criteria were defined for each round through descriptive statistics. Following completion of round 3 a list of clinical indicators that achieved consensus were generated.

RESULTS

Thirty-eight participants were recruited across 11 countries. Thirty-five participants completed round 1 (92.1%), 32 (84.2%) round 2 and 30 (78.9%) round 3. Round 1 identified consensus (Kendall's W coefficient of concordance 0.456; p < 0.001) for 10 clinical indicators out of the original 14, and 9 additional indicators were added to round 2 following content analysis of qualitative data. Round 2 identified consensus (Kendall's W coefficient of concordance 0.749; p < 0.001) for 10 clinical indicators out of 19, and 1 additional indicator was added to round 3. Round 3 identified consensus for 8 indicators (Kendall's W coefficient of concordance 0.648; p < 0.001). Following completion of the third round, an expert derived consensus list of 8 items was generated. Two indicators; pain variously described a burning, electric shock like and/or shooting into leg and pain in association with other neurological symptoms (e.g. pins and needles, numbness, weakness), were found to have complete agreement amongst expert participants.

CONCLUSIONS

Good agreement was found for the consensus derived list of 8 clinical indicators to identify NP in low back related leg pain. This list of indicators provide some indication of the criteria upon which clinicians can identify a NP component to low back related leg pain; further research is needed for stronger recommendations to be made.

Diagnostic utility of patient history, clinical examination and screening tool data to identify neuropathic pain in low back related leg pain: a systematic review and narrative synthesis

BACKGROUND

Low back-related leg pain (LBLP) is a challenge for healthcare providers to manage. Neuropathic pain (NP) is highly prevalent in presentations of LBLP and an accurate diagnosis of NP in LBLP is essential to ensure appropriate intervention. In the absence of a gold standard, the objective of this systematic review was to evaluate the diagnostic utility of patient history, clinical examination and screening tool data for identifying NP in LBLP.

METHODS

This systematic review is reported in line with PRISMA and followed a pre-defined and published protocol. CINAHL, EMBASE, MEDLINE, Web of Science, Cochrane Library, AMED, Pedro and PubMed databases, key journals and the grey literature were searched from inception to 31 July 2019. Eligible studies included any study design reporting primary diagnostic data on the diagnostic utility of patient history, clinical examination or screening tool data to identify NP in LBLP, in an adult population. Two independent reviewers searched information sources, assessed risk of bias (QUADAS-2) and used GRADE to assess overall quality of evidence.

RESULTS

From 762 studies, 11 studies were included. Nine studies out of the 11 were at risk of bias. Moderate level evidence supports a cluster of eight signs (age, duration of disease, paroxysmal pain, pain worse in leg than back, typical dermatomal distribution, worse on coughing/sneezing/straining, finger to floor distance and paresis) for diagnosing lumbosacral nerve root compression, demonstrating moderate/high sensitivity (72%) and specificity (80%) values. Moderate level evidence supports the use of the StEP tool for diagnosing lumbar radicular pain, demonstrating high sensitivity (92%) and specificity (97%) values.

CONCLUSIONS

Overall low-moderate level evidence supports the diagnostic utility of patient history, clinical examination and screening tool data to identify NP in LBLP. The weak evidence base is largely due to methodological flaws and indirectness regarding applicability of the included studies. The most promising diagnostic tools include a cluster of 8 patient history/clinical examination signs and the StEP tool. Low risk of bias and high level of evidence diagnostic utility studies are needed, in order for stronger recommendations to be made.

Diagnostic accuracy of self-report and subjective history in the diagnosis of low back pain with non-specific lower extremity symptoms: A systematic review

Subjective history questions/self-report items are commonly used to triage the patient with low back pain and related leg symptoms. However the value of the history taking process for decision-making to identify common classifications/diagnosis for patients presenting with low back related leg pain (LBRLP) have not been considered. The purpose of this study was to investigate the diagnostic accuracy of self-report items/history-taking questions used to identify patients with LBRLP. Eligible studies included: 1)subjects with low back pain AND related lower extremity pain, 2)details of subjective examination/self-report items, 3)cohort, prospective/longitudinal studies, and randomized control trials, 4)use of statistical reporting, 5)an acceptable reference standard. Quality was evaluated using the Quality Assessment of Diagnostic Accuracy Studies 2. A synthesis of history items that met the threshold for at least a small shift in the likelihood of the condition with a +LR ≥ 2 or -LR ≤ 0.5 were reported. Conditions commonly reported in the literature: lumbar spinal stenosis, lumbosacral nerve root compression/radiculopathy, disc herniation and neurophysiological low back pain ± leg pain. Eleven studies met the inclusion criteria. This is the first systematic review of diagnostic accuracy studies that examined only the history-taking items for their ability to identify LBRLP conditions. Clustering key items may provide a more precise clinical picture necessary to detect and treat a patient's presentation. History questions formed within the interview and their contributing value for decision-making remain understudied. There is a need for better designs to determine a more accurate diagnostic power to identify conditions with LBRLP.