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Freynhagen R, Baron R, Gockel U, Tölle TpainDETECT: a new screening questionnaire to detect neuropathic components in patients with back pain. Curr Med Res Opin 22: 1911-1920



Nociceptive and neuropathic components both contribute to pain. Since these components require different pain management strategies, correct pain diagnosis before and during treatment is highly desirable. As low back pain (LBP) patients constitute an important subgroup of chronic pain patients, we addressed the following issues: (i) to establish a simple, validated screening tool to detect neuropathic pain (NeP) components in chronic LBP patients, (ii) to determine the prevalence of neuropathic pain components in LBP in a large-scale survey, and (iii) to determine whether LBP patients with an NeP component suffer from worse, or different, co-morbidities. In co-operation with the German Research Network on Neuropathic Pain we developed and validated the painDETECT questionnaire (PD-Q) in a prospective, multicentre study and subsequently applied it to approximately 8000 LBP patients. The PD-Q is a reliable screening tool with high sensitivity, specificity and positive predictive accuracy; these were 84% in a palm-top computerised version and 85%, 80% and 83%, respectively, in a corresponding pencil-and-paper questionnaire. In an unselected cohort of chronic LBP patients, 37% were found to have predominantly neuropathic pain. Patients with NeP showed higher ratings of pain intensity, with more (and more severe) co-morbidities such as depression, panic/anxiety and sleep disorders. This also affected functionality and use of health-care resources. On the basis of given prevalence of LBP in the general population, we calculated that 14.5% of all female and 11.4% of all male Germans suffer from LBP with a predominant neuropathic pain component. Simple, patient-based, easy-to-use screening questionnaires can determine the prevalence of neuropathic pain components both in individual LBP patients and in heterogeneous cohorts of such patients. Since NeP correlates with more intense pain, more severe co-morbidity and poorer quality of life, accurate diagnosis is a milestone in choosing appropriate therapy.
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painDETECT: a new screening
questionnaire to identify
neuropathic components in
patients with back pain
Rainer Freynhagen
, Ralf Baron
, Ulrich Gockel
Thomas R. Tölle
Klinik für Anästhesiologie, Universitätsklinikum Düsseldorf, Düsseldorf,
Abteilung für Neurologische Schmerzforschung und –therapie, Universität
Kiel, Kiel, Germany
Pfizer Pharma GmbH, Karlsruhe, Germany
Klinik für Neurologie, Technische Universität München, München, Germany
Address for correspondence: Dr R. Freynhagen, MD, DEAA Klinik für Anästhesiologie,
Universitätsklinikum Düsseldorf, Moorenstraße 5, 40225 Düsseldorf, Germany.
Tel.: +49 211 811 6157;email:; and Professor R. Baron, MD,
Abteilung für Neurologische Schmerzforschung und therapie,Universität Kiel,Schittenhelmstr. 10,
24105 Kiel,Germany; Tel.: +49 431 597 8504; email:
Key words: Back pain – Co-morbidity – Neuropathic pain – Nociceptive pain – painDETECT
– Prevalence – Questionnaire
All rights reserved: reproduction in whole or part not permitted
VOL. 22, NO. ••, 2006, Fast Track PREPRINT: P1–P10
Paper 3586 P1
Objective: Nociceptive and neuropathic
components both contribute to pain. Since these
components require different pain management
strategies, correct pain diagnosis before and
during treatment is highly desirable. As low
back pain (LBP) patients constitute an important
subgroup of chronic pain patients, we addressed
the following issues: (i) to establish a simple,
validated screening tool to detect neuropathic
pain (NeP) components in chronic LBP patients,
(ii) to determine the prevalence of neuropathic
pain components in LBP in a large-scale survey,
and (iii) to determine whether LBP patients with
an NeP component suffer from worse, or different,
Methods: In co-operation with the German
Research Network on Neuropathic Pain we
developed and validated the painDETECT
questionnaire (PD-Q) in a prospective, multicentre
study and subsequently applied it to approximately
8000 LBP patients.
Results: The PD-Q is a reliable screening tool
with high sensitivity, specificity and positive
predictive accuracy; these were 84% in a palm-
top computerised version and 85%, 80% and
83%, respectively, in a corresponding pencil-and-
paper questionnaire. In an unselected cohort of
chronic LBP patients, 37% were found to have
predominantly neuropathic pain. Patients with
NeP showed higher ratings of pain intensity, with
more (and more severe) co-morbidities such as
depression, panic/anxiety and sleep disorders.
This also affected functionality and use of health-
care resources. On the basis of given prevalence
of LBP in the general population, we calculated
that 14.5% of all female and 11.4% of all male
Germans suffer from LBP with a predominant
neuropathic pain component.
Conclusion: Simple, patient-based, easy-to-
use screening questionnaires can determine the
prevalence of neuropathic pain components both
in individual LBP patients and in heterogeneous
cohorts of such patients. Since NeP correlates
with more intense pain, more severe co-morbidity
and poorer quality of life, accurate diagnosis is a
milestone in choosing appropriate therapy.
P2 painDETECT: screening for neuropathic pain © 2006 LIBRAPHARM LTD – Curr Med Res Opin 2006; 22(••)
Low back pain (LBP) is a common public health
problem world-wide
. For quite a number of patients
affected by the development of chronic back pain,
the disease is extremely disabling; it is likely to show
co-morbidity with mood disorders and is associated
with serious risk of ending in early retirement or an
inability to cope with activities of daily living. The
pathophysiological mechanisms of pain generation
in back pain are complex, current diagnostic tools do
not meet the patients needs in many respects, and
therapeutic results are frequently poor. However,
there is a consensus among many disciplines involved
in the treatment of back pain that the classification of
LBP disorders has to be based on the underlying mech-
anism, in order to allow formulation of clear treatment
recommendations and to ensure appropriate manage-
ment of the individual patient
. At the same time
there is a strong belief that the early inception of the
most appropriate treatment is most likely to avoid the
risk of developing chronic back pain.
In recent concepts for the understanding of back
pain, it is hypothesised that different components of
chronic pain, i.e. nociceptive and neuropathic com-
ponents, may both contribute to an individual’s pain.
In chronic back pain the nociceptive component
results from activation of nociceptors that innervate
ligaments, small joints, muscle and tendons. However,
at the same time, neuropathic processes may also be
. The current International Association for
the Study of Pain taxonomy defines neuropathic pain
as Pain resulting from a lesion or dysfunction of the
peripheral or central nervous system’. In a broad variety
of back-pain diagnoses it seems very likely that this is
indeed the case. Mechanical compression of radicular
nervous tissue may occur within or adjacent to the inter-
vertebral foramina, within the lateral recess and within
the spinal canal itself. In addition, the action of inflam-
matory mediators (cytokines, chemokines) originating
from the degenerative disc has been implicated in the
chemical pathomechanism of radicular neuropathic
Hence, a variety of nerve-damaging stimuli are likely
to generate a neuropathic pain component in patients
presenting with a chronic LBP. Significantly, many
long-term LBP patients report neurological deficits
and/or somatosensory positive symptoms that can
be described as characteristic of a neuropathic pain
component, i.e. hypoesthesia and allodynia. However,
this is only true if the clinical investigation is done
carefully and comprehensively, as these changes may
be subtle and escape routine examination. Since the
rationale for separating neuropathic pain from non-
neuropathic pain has direct implications for treatment,
it is of the utmost importance for the clinician to
identify the severity of the different pain components
in each individual patient. It is assumed that treatment
interventions based on particular pain mechanisms
(rather than treating pain as a uniform phenomenon)
will lead to increased ability to tailor specific therapies
to particular subgroups of patients.
Thus, primary care physicians have a key diagnostic
position since they guide the therapeutic management
from early on and have a pivotal role in triaging LBP
patients for specific treatment approaches
. Beside the
matter of pain treatment, LBP is in general associated
with numerous co-morbidities such as sleep disturb-
ance, depression and anxiety. Furthermore, other
fundamental questions have not yet been investi-
gated, and although such knowledge is essential
it is not known whether patients suffering from
pain of predominantly nociceptive origin differ from
those suffering from neuropathic pain components
(e.g. in respect of socio-demographic characteristics,
the intensity, duration or management of pain, co-
morbidities, functional disorders, pension applications
etc.). An effort to move forward towards a rational and
symptom-based treatment seems to be timely for the
improvement of LBP therapy. Therefore, physicians
should abandon any view of LBP as a monolithic entity
and, instead, distinguish the nociceptive and neuro-
pathic pain components and realise the co-morbid
conditions of their patients.
The purpose of screening tools is to identify patients
using a few key symptoms and signs. To encourage
their broad application such tools should be short and
easy to administer and most importantly independent
from physical examination. Several screening tools
for neuropathic pain have been developed and tested
with different patient populations but up to the
date when we started to develop our new questionnaire,
none of them met this need of primary care
physicians and moreover, none specifically targeted
Consequently, it is essential to focus on three unmet
(i) to establish a validated easy screening tool to
discriminate between neuropathic and noci-
ceptive pain components in a large-scale survey
of chronic LBP patients,
(ii) to provide the prevalence of neuropathic pain
components in LBP in the general population,
(iii) to answer the question of whether LBP
patients with a neuropathic pain component
suffer more severely than those without and,
if so, to substantiate the differences between
these two groups.
© 2006 LIBRAPHARM LTD – Curr Med Res Opin 2006; 22(••) painDETECT: screening for neuropathic pain Freynhagen et al. P3
We therefore set out to develop a screening tool
for neuropathic pain components specifically in LBP
patients using a simple patient-based questionnaire
(painDETECT questionnaire; PD-Q), that is both
reliable and easy to apply, either programmed into
hand-held palmtop computers (personal digital
assistant, PDA; e.g. in the context of a clinical trial),
or for simple routine use as a pencil-and-paper
painDETECT questionnaire
The aim was to develop an easy questionnaire to
detect neuropathic pain components, especially in
chronic LBP patients. Such a questionnaire should rely
on the characteristic clinical neuropathic symptoms.
Therefore, we performed a systematic review of the
literature, interviewed several national and international
pain experts and reviewed files of patients included
in the data base of the German Research Network
on Neuropathic Pain (Deutscher Forschungsverbund
Neuropathischer Schmerz, DFNS) to find out how
neuropathic pain symptoms are perceived by the
patient. As a result, seven questions that address the
quality of neuropathic pain symptoms (Table 1) were
included in the questionnaire. Different questions were
not tested or discarded. Furthermore, it became clear
that many patients described distinct pain patterns
during the course of the disease that might be of
predictive value to distinguish neuropathic from noci-
ceptive pain. Lastly, the description ‘radiating pain’ was
found to be a neuropathic descriptor, in particular when
LBP patients were interviewed. Following selection of
the most appropriate items, a principal-components
analysis (PCA) was performed. Kaiser’s criterion was
then applied, thus retaining for further analysis only
those factors with an eigenvalue of 1.0 or greater.
Validation study
In a prospective multicentre study, 411 pain patients
were recruited consecutively at ten specialised pain
centres and screened for participation. In accordance
with the current gold standard (diagnoses by expert
pain physicians to assess the predominant pain type),
each patient was examined by two experienced pain
specialists, working independently of each other, at
each centre. Both specialists assessed the predominant
pain type on the basis of his/her experience, using
whatever diagnostic methods were considered appro-
priate (neurological or electrophysiological examination,
imaging, etc.). The assessments were not performed until
all additional data were available. They were required to
rate the pain as predominantly neuropathic, nociceptive
or unclear. To reduce the error ratio within the validation
study and to enlarge the reliability of a diagnosis of
Item Score
Gradation of pain*
Do you suffer from a burning sensation (e.g. stinging nettles) in the marked areas?
Do you have a tingling or prickling sensation in the area of your pain (like crawling ants or electrical tingling)?
Is light touching (clothing, a blanket) in this area painful?
Do you have sudden pain attacks in the area of your pain, like electric shocks?
Is cold or heat (bath water) in this area occasionally painful?
Do you suffer from a sensation of numbness in the areas that you marked?
Does slight pressure in this area, e.g. with a finger, trigger pain?
Pain course pattern 
Please select the picture that best describes the course of your pain:
Persistent pain with slight fluctuations
Persistent pain with pain attacks
Pain attacks without pain between them
Pain attacks with pain between them
Radiating pain 
Does your pain radiate to other regions of your body? Yes/No +2/0
*For each question: never, 0; hardly noticed, 1; slightly, 2; moderately, 3; strongly, 4; very strongly, 5
Questions used to document pain, but which were not used in the scoring, are not shown
Table 1. painDETECT questionnaire
P4 painDETECT: screening for neuropathic pain © 2006 LIBRAPHARM LTD – Curr Med Res Opin 2006; 22(••)
either predominantly neuropathic or nociceptive pain
only patients diagnosed with typical’ neuropathic or
nociceptive entities were included. Pain of predominantly
neuropathic origin (n = 228) included post-herpetic
neuralgia (PHN), painful polyneuropathy (PNP), nerve
trauma and low back pain (solely of the lumbar vertebrae,
sacrum and coccyx) diagnosed as predominantly
neuropathic. Pain of predominantly nociceptive origin
(n = 164) included visceral pain, osteoarthritis,
inflammatory arthropathies and mechanical LBP (source
of pain is in the spine and/or its supporting structures
such as surrounding muscles, ligaments, joints or soft
tissues). A patient was included in the validation cohort
(i) if, and only if, the two specialists concurred in
the diagnosis,
(ii) the diagnosis was not ‘unclear’,
(iii) the patients average pain was stated by the
patient to be at least 40% on a visual analogue
scale (VAS) from 0 (no pain) to 100% (worst
possible pain), and
(iv) the patient was able to answer unaided
the German-language questionnaire on the
If a patient was diagnosed with pain of assumed
mixed origin (e.g. malignancy, compression fractures,
fibromyalgia, ancylosing spondylitis) or if the
symptomatology was unclear the patient was explicitly
The result of the experts’ opinion was then compared
with results of the PD-Q. The true diagnoses
(predominantly neuropathic pain: Yes/No) were used
as a target variable in logistic regression model. The
seven questions to characterise neuropathic pain, the
pain course pattern and the presence or absence of
radiating pain were included in the model. The ROC
(receiver operating characteristic) and area under the
curve were determined.
Our approach was driven by physicians needs
to be able to detect patients with predominantly
neuropathic pain, with high probability (> 80%);
the results of the logistic regression model were
approached by an empirical procedure using all the
parameters as described, easily combined to evaluate
patients’ answers in everyday consultation. This led to a
pencil-and-paper questionnaire version with an
expansion of the score range from (0, 35) to (–1, 38).
Internal consistency is reported as Cronbach’s alpha
Epidemiological survey
Five hundred PDAs (Palm Tungsten E, operating
system Palm OS 5.4) were issued to 472 general and
specialist practices and hospitals throughout Germany
(including 158 general practitioners, 45 orthopaedists,
67 neurologists and 202 pain specialists). A total
of 7772 patients with various forms of chronic low
back pain (lower back pain that lasts for longer than
3 months) were consecutively included in the study if
they fulfilled the inclusion and exclusion criteria. To
be included in the epidemiological survey low back
pain had to be the leading pain problem (e.g. with
the maximum pain localisation) but patients with
additional back pain problems (cervical, neck or upper
back problems, secondary chronic muscle tension, etc.)
were not excluded.
Apart from PD-Q, the following questionnaires
were used: the Medical Outcomes Study sleep
scale (MOS)
, the German-language Patient Health
Questionnaire (PHQ-9, short form)
, and the Hanover
Functional Ability Questionnaire for measuring back-
pain-related disability (FFbH-R)
. All of these are
validated and in common use. The programming
included automated plausibility checks that gave the
user a warning if impossible values were keyed in. At
intervals, PDAs were collected and data transfer and
processing were performed under secure conditions,
with anonymisation and encryption. Before the study,
investigators were introduced to the study procedures;
apart from this and PDA collection, further monitoring
was not considered appropriate. Physicians did not
receive a financial incentive for taking part in the
epidemiological study.
Study population
Patients presenting with chronic LBP, at least 18 years
old and after giving informed consent, were requested
to complete the PDA questionnaires, within either
the validation study or the epidemiological survey.
Recruiting took place from August 2004 to May 2005.
The study protocol and consent forms of the study
were submitted to and approved by the local ethics
committee, in accordance with the ethical principles
originating from the Declaration of Helsinki and in
compliance with Good Clinical Practice.
Data management and statistical analysis
Information from the paper forms was transferred to
the project data base by double data-entry, followed
by data review. Afterwards, the paper and PDA data
sources were merged for descriptive statistical analyses;
these were performed with the SAS package, version
8.2. Graphics were generated with SPSS version 11.5.
Patients were grouped into classes based on results of
the validation study regarding the painDETECT score.
Correlations between scores and continuous variables
© 2006 LIBRAPHARM LTD – Curr Med Res Opin 2006; 22(••) painDETECT: screening for neuropathic pain Freynhagen et al. P5
were calculated using Pearson correlation coefficient.
Relations between two dichotomous variables were
assessed by 2 × 2 contingency tables. An ANOVA
model was used to evaluate differences between groups
of patients.
Validation study
The level of patients acceptance of the PDA
questionnaire was very high: 80% had no problems,
10% minor problems and only 10% required assistance.
In all, 411 patients were screened in the validation
study; of these 19 were excluded (ten because of
diagnosis of an unclear pain and nine because the raters
differed in assessment of the pain type). Results for
the remaining 392 patients (pain of predominantly
nociceptive origin, n = 164; pain of predominantly
neuropathic origin, n = 228) were evaluated by
logistical regression and are depicted in Figure 1(A),
which plots the cumulative frequency of scores on the
painDETECT scale up to 38. The corresponding curves
for the entire 392-patient population allow an equally
clear inference to be made [Figure 1(B)].The set of
392 patients was used in a logistical regression analysis
to establish the sensitivity (which indicates how good
a test is at correctly identifying people who have the
disorder in question), specificity (which indicates how
good a test is at correctly identifying people who do
not have the disorder) and the probability of correct
assignment (positive predictive value refers to the
chance that a positive test result will be correct) of the
PD-Q. Results are displayed in Figure 2.
The PD-Q score is calculated by addition of the
entries in the right-hand column of the questionnaire
(maximum possible score = 38, minimum = 1; only
integral values are possible). For screening purposes
the following cut-off points have been found to be
the most appropriate: score ≤ 12, a neuropathic com-
ponent is unlikely (< 15%); score ≥ 19, a neuropathic
component is likely (> 90%). Between these, the result
is uncertain, i.e. a neuropathic pain component can be
present. The logistic regression indicated a sensitivity
of 84%, and a specificity and probability of correct
assignment, likewise, of 84%. When the score was
subjected to an empirical analysis for use as a pencil-
and-paper questionnaire, then the values found for
these were 85%, 80% and 83%, respectively. The area
under the curve for the logistical regression analysis was
found to be 0.91 (Figure 2); the theoretical maximum
is 1.00 for perfect discrimination). Repetition of the
(A) (B)
0 5 10 15 20 25 30 35 38
painDETECT score
0 5 10 15 20 25 30 35
painDETECT score
0 20 40 60 80 100
1 – Specifity (%)
Sensitivity (%)
Figure 1. (A)Cumulative frequency of scores on the painDETECT scale for various pain types. Key:red,nociceptive LBP 
(n = 100); blue, other nociceptive pain (n = 64); green,neuropathic LBP (n = 52),mauve, other neuropathic pain (n = 132);
orange,DPN and PHN only (
n = 44).(B) The corresponding curves for the entire 392-patient population: red, all pain 
diagnosed as nociceptive in origin (
n = 164); green, all pain diagnosed as neuropathic in origin (n = 228)
Figure 2. ROC curve of logistic regression model (blue) and ROC curve of empirical painDETECT score (orange). The area 
under the curve for the logistic regression model is 0.91
P6 painDETECT: screening for neuropathic pain © 2006 LIBRAPHARM LTD – Curr Med Res Opin 2006; 22(••)
calculation for the LBP patients only led to similar
results, with slightly higher values.
According to the Kaiser criterion, four factors of
formal importance (eigenvalue of 1.0) could be
identified, of which two were found to be determin-
ative, as follows. The data structure of the pain course
pattern is dominated by the first principal component,
which consists of the seven questions about pain
quality. The second interpretable principal component
is dominantly described by the pain course pattern
‘Pain attacks with pain-free periods in between’ (one of
four, cf. Table 1) and ‘Radiating pain’. Considering the
first principal component, the bivariate correlations
between the seven items to grade pain were always
significant, with p < 0.001 (n = 392). These seven
items demonstrated adequate internal consistency
(Cronbach’s alpha = 0.83).
Epidemiological survey
A total of approximately 8000 patients with various
chronic back pain problems took part in the survey.
Of these, 7772 yielded complete data sets. The demo-
graphic profile of these patients is shown in Table 2.
Conspicuously, the percentage of patients with a PD-Q
score of ≥ 19 (synonymous with a probability of having
a neuropathic pain component > 90%) was high. The
prevalence of LBP patients with a NeP component
was found to be 37% (males, 36.9%; females, 37.1%).
Furthermore, our data demonstrate striking differences
between LBP patients with and without a neuropathic
pain component. Regarding the duration of pain
treatment, the number of physician visits for pain in
the past 4 weeks, the number of different therapists
(including on-going psychotherapy), the proportion
of intended or submitted pension applications and
the average pain intensity during the past 4 weeks,
LBP patients with a NeP component were found to
suffer longer and more severely (
p < 0.001; Table 2).
The breakdown of demographic and disease-related
variables by PD-Q score and thus by the likely
involvement of different pain components reveals
various trends, and these are summarised in Table 3.
On the PHQ-9 scale for depression, scores were
rated as follows: 04 (none), 59 (mild), 1019
(moderate) and 2027 (severe). As Table 3 shows,
the proportion of patients with severe depression is
greatest in the neuropathic pain’ group (
p = 0.001).
Of the subjects without a NeP component, 63.7%
(n = 1727) met the criteria for depression. Their
median PHQ-9 score (possible maximum 27) was 6.0
(mean 7.1; SD 5.0). In contrast, among the patients
with a NeP component, 91.6% (n = 2605) of subjects
met the criteria for depression, and their PHQ-9 score
was doubled (median 12.0; mean 12.3; SD 5.8). We
found a strong association between depression severity
and the PD-Q score (Pearson correlation coefficient =
0.43; p < 0.001). The corresponding odds ratios for
mild, moderate and severe depression were found to be
3.2, 8.9 and 25.9, respectively.
Panic/anxiety disorder
According to the PHQ-9 screening, 6747 patients were
evaluable for panic/anxiety disorders; 707 (10.5%)
revealed the presence of these (Table 3). Here again a
correlation was seen, with approximately four times as
many patients in the neuropathic’ group than in the
nociceptivegroup (
p < 0.001). The corresponding
odds ratio was 4.5 (95% confidence limits [3.6, 5.6];
Table 3).
Sleep disorders
The MOS sleep questionnaire was evaluated such as to
record for each patient ‘optimal sleep’, ‘sleep disturb-
ance’, ‘somnolence’, ‘sleep quality’ and ‘sleep adequacy’.
The correlation seen is unusually clear: in each case a
clear and substantial worsening was observed with rising
PD-Q score for all reported items (
p < 0.001; Table 3).
Intensity of back pain (VAS)
This also increased markedly with rising PD-Q score
p < 0.001), and neuropathic patients had more severe
pain with significantly higher current, average and
worst pain scores on the VAS than the nociceptive’
group (Table 2).
The FFbH-R scale provides the percentage of remain-
ing functionality of the patient as compared with a
healthy subject under everyday conditions. There was
a clear decrease in functionality with increasing PD-Q
Score (
p < 0.001). Table 3 illustrates clearly how a NeP
component in the majority of the sufferers severely
affects functionality.
Our results are noteworthy because of three major
First of all, we established a reliable, simple and
validated screening tool to predict the likelihood of a
neuropathic pain component in chronic pain disorders,
© 2006 LIBRAPHARM LTD – Curr Med Res Opin 2006; 22(••) painDETECT: screening for neuropathic pain Freynhagen et al. P7
for use either in hand-held computers (e.g. in clinical
trials) or as a pencil-and-paper questionnaire (in routine
practice). In the validation, the PD-Q showed a slightly
higher sensitivity and specificity in comparison with
other screening questionnaires for neuropathic pain
such as DN4
, the NPQ
or the NPS
. It
can easily be applied fully by the patient, without any
prior physical examination by medical personnel. It is
the first tool to use unique pain patterns as a principal
component and, while it incorporates radiation, it is
particularly suitable for initial screening on LBP, for
example in the waiting-room or (if necessary, blinded)
in the context of a clinical trial, in order to distinguish
between pathophysiological subgroups that are
assumed to respond differently to a drug under study.
The level of patientsacceptance of the PDA version
was very high.
Our validation study has a number of strengths.
The findings are based on a large, multicentre sample
(n = 392), and the pain classification used in developing
and validating the PD-Q was based upon the current
gold standard – i.e. diagnoses by expert pain physicians
based upon all available criteria. Unlike other screening
questionnaires, the PD-Q validation also included
LBP diagnosed as predominantly neuropathic or
nociceptive in origin. In addition, the validation
Table 2. Socio-demographic and clinical characteristics of the low back pain population
painDETECT score
Patients, n (%) 2743 (35.3%) 2153 (27.7%) 2876 (37.0%) 7772 (100%)
male, n (%)
1010 (36.8%) 823 (38.2%) 1070 (37.2%) 2903 (37.4%)
female, n (%) 1733 (63.2%) 1330 (61.8%) 1806 (62.8%) 4869 (62.6%)
Age (years)* 53.4 ± 15.1 52.6 ± 13.1 51.5 ± 11.9 52.5 ± 13.4
P25–P75 41.0–65.0 42.0–63.0 42.0–60.0 42.0–63.0
Height (cm)*
males 178 ± 7 178 ± 7 178 ± 7 178 ± 7
females 165 ± 6 165 ± 6 166 ± 6 165 ± 6
Weight (kg)*
males 85 ± 13 86 ± 16 87 ± 14 86 ± 14
females 71 ± 13 72 ± 14 73 ± 15 72 ± 14
BMI (kg/m
males 26.9 ± 3.9 27.0 ± 4.2 27.4 ± 4.0 27.1 ± 4.0
females 26.0 ± 4.8 26.4 ± 4.7 26.8 ± 5.3 26.4 ± 5.0
Pain treatment (months)* 56 ± 85 67 ± 88 73 ± 90 65 ± 88
P25–P75 25.0–67.0 10.0–82.0 14.0–93.0 9.0–80.0
Number of visits to a physician for pain in the past 4 weeks
no visit, n (%)
553 (20.2%) 253 (11.8%) 197 (6.8%) 1003 (12.9%)
1 visit, n (%)
830 (30.3%) 607 (28.2%) 663 (23.1%) 2100 (27.0%)
2 visits, n (%)
657 (24.0%) 582 (27.0%) 735 (25.6%) 1974 (25.4%)
3 or more, n (%) 703 (25.6%) 711 (33.0%) 1281 (44.5%) 2695 (34.7%)
Number of different therapists* 1.7 ± 1.3 2.0 ± 1.4 2.5 ± 1.6 2.1 ± 1.5
P25–P75 1.0–3.0 1.0–3.0 1.0–3.0 1.0–3.0
Ongoing psychotherapy, n (%) 152 (5.5%) 183 (8.5%) 356 (12.4%) 691 (8.9%)
Intended or submitted pension application, n (%) 403 (14.7%) 551 (25.6%) 1235 (42.9%) 2189 (28.2%)
Average pain intensity recorded on VAS during the past 4 weeks, n (%)
mild 651 (23.7%) 303 (14.1%) 177 (6.2%) 1131 (14.6%)
moderate 1532 (55.9%) 1258 (58.4%) 1462 (50.8%) 4252 (54.7%)
severe 560 (20.4%) 592 (27.5%) 1237 (43.0%) 2389 (30.7%)
VAS worst pain* 7.0 ± 2.2 7.6 ± 1.9 8.1 ± 1.6 7.6 ± 2.0
VAS average pain* 5.2 ± 2.0 5.8 ± 1.9 6.6 ± 1.8 5.9 ± 2.0
VAS current pain* 4.6 ± 2.4 5.5 ± 2.2 6.5 ± 2.1 5.5 ± 2.4
*Mean ± standard deviation
BMI, body mass index; VAS, visual analogue scale from 0 to 10; P25/P75, 25% and 75% percentiles
Percentages are given by painDETECT score group, except in the top row, where the basis is the row total
Exploratory comparisons between patients with painDETECT score ≤ 12 versus patients with painDETECT score ≥ 19 were carried out
cross-tabulation for categorical data). p values were < 0.001 for all comparisons except the rate of patients with two
physician’s visits in the past 4 weeks. Regarding demographic characteristics painDETECT score groups were comparable
P8 painDETECT: screening for neuropathic pain © 2006 LIBRAPHARM LTD – Curr Med Res Opin 2006; 22(••)
process fulfilled the criteria for validation of pain
. To ensure validity of content, a large
patient database from the DFNS was reviewed, expert
clinical opinion was obtained and the relevant pain
literature was consulted; this validity was borne out by
the principal-components analysis as applied to the set
of items presented in Table 1 and the use of Kaiser’s
criterion (see Methods). Although traditionally the
diagnosis of NeP relies largely on medical history and
sensory examination, there is still no absolute test for
neuropathic pain available. However, our gold standard-
based approach, involving two experts working
independently of each other and using all available
diagnostic methods, represents the most objective
classification into neuropathic and nociceptive pain
that can currently be attained. Furthermore, the very
small number of inter-rater discrepancies (9/411, or
2%) confirms the reliability of the reference standard.
Also, the score distributions of patients with different
disorders of similar algogenetic nature are comparable
[Figure 1(A)]. Hence, these ‘true’ diagnoses were then
used as reference variable in the logistic regression
model. Moreover, the PD-Q questions require graded
answers, rather than binary yes/no responses or a
visual analogue scale. This fine division may enhance
the questionnaire’s value, not only as a research tool
for monitoring clinical progress or helping to discover
pathogenic mechanisms in clinical studies, but also in
daily clinical practice.
The validation study has some potential limitations.
While it took account of a number of likely important
variables based on a large base of patient data, an
analysis of the current literature and experts’ clinical
experience, the possibility cannot be excluded that
some other factor or set of factors associated with
neuropathic, nociceptive, or both types of pain may
have been omitted. The validation did not include a
‘test–retest’; this we considered ethically and scientif-
ically unjustifiable, the former because it would have
required withholding or interrupting treatment of
the patients pain, and the latter because pain does
not necessarily remain stable from one day to the next,
so that testretest stability coefficients have only
limited utility as estimates of the reliability of pain
The classification of NeP based on mechanisms,
aetiology or location has considerable shortcomings
while several studies have shown that the presence of a
cluster of symptoms allows separation of NeP from non-
neuropathic pain
other workers, who failed to find
a single symptom or descriptor, contradict this idea
However, patients ultimately report symptoms rather
than pain mechanisms and, therefore, the development
and validation of screening tools for identifying NeP on
the basis of symptoms and signs seems to be the most
rational way to improve the use of questionnaires in
daily clinical routine
Our second finding is the demonstration, in a large
representative survey of approximately 8000 patients
with LBP, that 37.0% (n = 2876) had a predominantly
neuropathic type of pain (PD-Q scores 19) and
35.3% (n = 2743) a predominantly nociceptive type
of pain (PD-Q scores ≤ 12). To estimate how many
patients are affected in the whole of Germany, we
Table 3. Summary of the epidemiological results for various co-morbidities
painDETECT score:
≤ 12 13–18 ≥ 19
Odds ratio†
PHQ-9 score, depression
None (0–4) 985 (36.3%) 383 (18.0%) 239 (8.4%) < 0.001
Mild (5–9) 992 (36.6%) 834 (39.1%) 775 (27.3%) < 0.001 3.2
Moderate (10–19) 676 (24.9%) 821 (38.5%) 1460 (51.3%) < 0.001 8.9
Severe (20–27) 59 (2.2%) 94 (4.4%) 370 (13.0%) < 0.001 25.9
Panic/anxiety disorder present 105 (3.9%) 163 (7.6%) 439 (15.4%) < 0.001 4.5
MOS sleep scale
Optimal sleep 1310 (47.8%) 825 (38.4%) 703 (24.5%) < 0.001 0.4
Sleep disturbance 38.5 ± 24.4, 36 48.0 ± 22.7, 46 59.0 ± 61.0, 61 < 0.001
Somnolence 36.1 ± 21.9, 33 42.7 ± 21.2, 40 50.9 ± 21.3, 53 < 0.001
Sleep quality 6.5 ± 1.4, 7 6.1 ± 1.5, 6 5.6 ± 1.6, 6 < 0.001
Sleep adequacy 52.8 ± 27.7, 50 44.2 ± 26.5, 40 35.2 ± 25.2, 30 < 0.001
FFbH-R functionality (0–100%) 62.3 ± 24.0, 62 52.8 ± 22.4, 50 41.4 ± 21.2, 41 < 0.001
For PHQ-9 and ‘optimal sleep’, n and % are given; percentages are given by group; for the remaining variables, mean ± standard deviation
and median are given
*p values for exploratory comparisons between patients with painDETECT score ≤ 12 versus patients with painDETECT score ≥ 19
cross-tabulation for categorical data)
†Odds ratios for the various PHQ-9 scores describe patients with the respective grading of depression compared with patients without
© 2006 LIBRAPHARM LTD – Curr Med Res Opin 2006; 22(••) painDETECT: screening for neuropathic pain Freynhagen et al. P9
took into account the latest data from the Robert
Koch Institute on chronic back pain
. On the basis
of given prevalence of LBP in the general population,
we calculated that 14.5% of all female and 11.4% of
all male Germans suffer from LBP with a predominant
neuropathic pain component. Hence, NeP is a major
contributor to chronic LBP, and a correct differential
diagnosis to detect the most likely operating
pain type is essential. The distinction between
neuropathic and nociceptive pain types and the
estimation of its relevance are crucial, since the
different pain types require different therapeutic
approaches. Although non-steroidal anti-inflammatory
drugs are still the first-line drugs for chronic
, sufficient evidence for their use in chronic
or NeP
is lacking. However, there is strong
evidence that opioids, cyclic antidepressants and
anticonvulsants are equally effective for the treatment
of NeP and, in addition, the realisation that symptoms
other than pain are sometimes more important and/
or easier to overcome can increase the benefits of
It is important to note that the search of the specific
diagnosis of the disease needs to be performed without
delay as in some cases the identification of a neuro-
pathic component may reflect the need of disc surgery
or in rare cases even malignancy. However, although
screening tools can not replace clinical judgment in the
assessment of an individual patient’s pain they can at
least alert clinicians to undertake prompt further diag-
nostic evaluation which may subsequently influence
pain management.
Thirdly, the present study reveals fundamental
differences, in respect of perceived pain and of various
co-morbidities, between LBP patients with neuropathic
and those with nociceptive components. The additional
effect on peripheral nerves in low back pain obviously
leads to considerable changes in the entire central
processing of nociceptive information in the brain,
as well as to more (and more distinct) co-morbidities
such as depression, panic/anxiety disorder and sleep
disturbance, seriously affecting the quality of patients’
lives. NeP patients appeared more likely to have a lower
residual functionality under everyday conditions and
to suffer longer and with a more severe pain intensity.
On the basis of average pain intensity reported for the
past 4 weeks 43% were suffering severe pain (pain
score > 7–10 on an 11-point scale
), compared
with 24% in the nociceptive group. NeP patients
had more frequent visits to physicians and more
different therapists, more psychotherapy, a longer
duration of pain treatment and made pension
applications earlier. These findings illustrate the impact
of the NeP component on health-care resource util-
isation. As we demonstrated, the detrimental effects
of NeP ultimately result in a decreased quality of life,
so that our results imply that separating predominantly
neuropathic from non-neuropathic pain components
should be made a central goal in the management
of LBP.
Growing evidence exists to support a multidisciplin-
ary therapeutic approach, and physicians should follow
clinical practice guidelines in their daily management
of LBP
. The integral role played by psychological
and social factors in LBP is still largely ignored;
attention to it is reserved for patients who do not
respond to cheaper treatment options. However,
our finding that a NeP component has such an
immense impact on the burden of the individual
sufferers was an unexpected result of our study and,
therefore, at least a cheap and simple screening on the
presumed pain type should be performed to sensitise
the physician towards potential co-morbidity problems.
This study demonstrates that the PD-Q is a valuable
tool that may cover an unmet need. It is currently
being developed for application in different linguistic
and cultural contexts.
The PD-Q developed, validated and applied to 8000
LBP patients constitutes a new, reliable and simple
screening tool to predict the likelihood of a neuropathic
pain component being present in individual patients
and in inhomogeneous cohorts of LBP patients. The
present findings demonstrate a high prevalence of LBP
patients with a predominant NeP component (37%)
and provide important information on the association
between NeP and the occurrence and severity of
different co-morbidities. Patients with a neuropathic
pain component suffer more (and more severe) than
those without. The future use of the PD-Q may be
helpful both in clinical research and daily clinical
Declaration of interest: This research was supported by
Pfizer Pharma GmbH, Germany, without restriction
on publication. UG is an employee of Pfizer Germany.
RF, RB and TRT received research support, consult-
ancy and lecture fees from a number of pharmaceutical
companies but have no direct stock holding in any of
them. The authors would like to thank all participating
patients, colleagues and the staff of the institutions for
their contributions to data collection. The research
benefited from the technical and statistical support of
StatConsult GmbH, Germany.
P10 painDETECT: screening for neuropathic pain © 2006 LIBRAPHARM LTD – Curr Med Res Opin 2006; 22(••)
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CrossRef links are available in the online published version of this paper:
Paper CMRO-3586_3, Accepted for publication: 16 August 2006
Published Online:
00 September 2006
... AMG enables noninvasive, quick, and reliable muscle assessment, and it lends itself to home measurement of subjects performing daily tasks over a number of hours (Claudel et al., 2018;Harrison, 2018;Harrison et al., 2013). Pain assessment was included in this study to determine and exclude possible muscle disease clinically presented by pain (Freynhagen et al., 2006). AMG has the potential to accurately assess muscle fiber activity, thereby indicating precisely how an individual muscle is activated and regulated during any given function. ...
... AMG has the potential to accurately assess muscle fiber activity, thereby indicating precisely how an individual muscle is activated and regulated during any given function. The method has, apart from studies on healthy subjects (Bartels, Ahmed, et al., 2020;Claudel et al., 2018;Freynhagen et al., 2006), successfully been applied in cerebral palsy (CP) subjects, where a different recruitment pattern of muscle fibers was seen (Pingel et al., 2019). ...
... The inclusion criteria for healthy subjects were as follows: 18.5 < BMI < 30; healthy according to an examination by a physician (MC); reporting of no chronic neuromuscular or movement disorder; no earlier history of affection of the nervous system or no present illness; pain reported in the normal range and pattern for healthy subjects from answering the PainDETECT Questionnaire (PD-Q) ©2005 Pfizer Pharma GmbH (Freynhagen et al., 2006) prior to participation and ability to understand instructions in Danish and to answer questionnaires in Danish. ...
Full-text available
Acoustic myography (AMG) noninvasively probes muscle activity. We explored whether AMG captures abnormal motor activity in patients with Parkinson's disease (PD) and how this activity is modulated by antiparkinsonian medication. Twenty patients with PD underwent AMG of the biceps, triceps, extensor carpi radialis longus, and adductor policis muscles of the more affected arm during active and passive movements, using a mobile AMG device (CURO, Denmark). AMG and assessment of motor symptoms were performed in a pragmatic off-medication state, as well as one and 3 h after oral intake of 200 mg levodopa. Three AMG parameters were calculated using the CURO analysis system. Motor efficiency was expressed by the E-score, muscle fiber recruitment by the temporal T-score, spatial summation by the S-score, and S/T ratio. Twenty age- and sex-matched healthy subjects served as controls. Group mean values were statistically compared using unpaired two-tailed adjusted t-test and ANOVA with Tukey´s correction for multiple comparison (p ≤ 0.05). For the biceps and extensor carpi radialis longus muscles, the active movement S:T ratio was lower in PD relative to healthy controls. The E-score was also lower during active and passive flexion/extension movements in the off-medication state. No significant between-group differences in the AMG scores were noted for the triceps muscle during active or passive movements. The active S:T ratio and the E-score during active elbow flexion and extension may offer a useful means to quickly assess abnormal motor activity and the effect of drug treatment in PD.
... 39 The PainDETECT questionnaire detects the neuropathic pain components, and higher scores indicate higher neuropathic pain. 40 The Pain Catastrophizing Scale evaluates pain catastrophizing defined as "an exaggerated negative mental set brought to bear during actual or anticipated painful experience", and higher scores indicate greater catastrophizing. 41 The Geriatric Depression Scale is a screening tool for depressive symptoms with 15 items, and higher scores indicate a greater likelihood of depression. ...
... Some patients complain strongly of spontaneous pain, tingling sensations, and electric-shock-like pain, while others suffer from hypersensitivity to light touch or temperature. A simple and validated patientreported screening questionnaire, painDETECT, can detect these characteristic sensory abnormalities (4,5). Researchers have attributed this difference in pain patterns to the relative contributions of the peripheral and central mechanisms (6). ...
Full-text available
Background and goal of study Patients with zoster-associated pain exhibit a variety of sensory symptoms and forms of pain and complain of different pain patterns. The purpose of this study is to subgroup patients with zoster-associated pain who visited a hospital using painDETECT sensory symptom scores, analyze their respective characteristics and pain-related data, and compare similarities and differences among the groups. Materials and methods The characteristics of 1,050 patients complaining of zoster-associated pain and pain-related data were reviewed retrospectively. To identify subgroups of patients with zoster-associated pain according to sensory symptom profiles, a hierarchical cluster analysis was performed based on the responses to a painDETECT questionnaire. Demographics and pain-related data were compared among all subgroups. Results and discussion Patients with zoster-associated pain were classified into 5 subgroups according to the distribution of sensory profiles, with each subgroup exhibiting distinct differences in the expression of sensory symptoms. Patients in cluster 1 complained of burning sensations, allodynia, and thermal sensitivity, but felt numbness less strongly. Cluster 2 and 3 patients complained of burning sensations and electric shock-like pain, respectively. Cluster 4 patients complained of most sensory symptoms at similar intensities and reported relatively strong prickling pain. Cluster 5 patients suffered from both burning and shock-like pains. Patient ages and the prevalence of cardiovascular disease were significantly lower in cluster 1. Patients in clusters 1 and 4 reported longer pain duration compared with those in clusters 2 and 3. However, no significant differences were found with respect to sex, body mass index, diabetes mellitus, mental health problems, and sleep disturbance. Pain scores, distribution of dermatomes and gabapentinoid use were also similar among the groups. Conclusions Five different subgroups of patients with zoster-associated pain were identified on the basis of sensory symptoms. A subgroup of younger patients with longer pain duration showed specific and distinct symptoms, such as burning sensations and allodynia. Unlike patients with acute or subacute pain, patients with chronic pain were associated with diverse sensory symptom profiles.
... Finally, we also did not find any significant correlations between the PCS-R scores and ΔRTv (Figure 9 3.4. Supplemental analysis: pain scores in ankylosing spondylitis group, sex differences in task performance and metrics of attention to pain As a supplementary exploratory analysis, pain intensity scores at the time of testing and on average over 4 weeks were obtained from the AS group using the painDETECT questionnaire, and compared across the A-and P-types (30,31). There was no statistically significant differences in current (i.e., state) pain scores across A-and P-types. ...
Full-text available
Two behavioural phenotypes in healthy people have been delineated based on their intrinsic attention to pain (IAP) and whether their reaction times (RT) during a cognitively-demanding task are slower ( P -type) or faster (A-type) during experimental pain. These behavioural phenotypes were not previously studied in chronic pain populations to avoid using experimental pain in a chronic pain context. Since pain rumination (PR) may serve as a supplement to IAP without needing noxious stimuli, we attempted to delineate A-P/IAP behavioural phenotypes in people with chronic pain and determined if PR can supplement IAP. Behavioural data acquired in 43 healthy controls (HCs) and 43 age-/sex-matched people with chronic pain associated with ankylosing spondylitis (AS) was retrospectively analyzed. A-P behavioural phenotypes were based on RT differences between pain and no-pain trials of a numeric interference task. IAP was quantified based on scores representing reported attention towards or mind-wandering away from experimental pain. PR was quantified using the pain catastrophizing scale, rumination subscale. The variability in RT was higher during no-pain trials in the AS group than HCs but was not significantly different in pain trials. There were no group differences in task RTs in no-pain and pain trials, IAP or PR scores. IAP and PR scores were marginally significantly positively correlated in the AS group. RT differences and variability were not significantly correlated with IAP or PR scores. Thus, we propose that experimental pain in the A-P/IAP protocols can confound testing in chronic pain populations, but that PR could be a supplement to IAP to quantify attention to pain.
... Presence of neuropathic pain The PainDetect Questionnaire (Freynhagen et al., 2006) is a reliable screening tool to predict the likelihood of a neuropathic pain component composed of 12 items with a 6level Likert scale and numerical scale of 0-10. The total score is a sum of all items and indicates if the pain is less likely to be neuropathic (i.e., 0-12 nociceptive pain; 13-18 mixed pain; 19-38 most likely neuropathic pain). ...
Treatment of neuropathic pain in general, and in diabetic neuropathy in particular, often results in inadequate pain relief, even with first-line drugs. New therapeutic approaches are therefore mechanism-based targeting the individual pathophysiological pain mechanisms. The sensory phenotype of a patient, i.e., the sensory signs and symptoms, can provide indirect information about these underlying pathomechanisms. Quantitative sensory testing (QST) can be used to assess the function of the large and small nerve fibers or the corresponding central pathways to generate an individual sensory profile with loss and gain of function parameters for each patient. Stratification of patients according to these profiles can help to identify subgroups of patients with similar pathophysiological mechanisms. In diabetic neuropathy the most frequent subgroup is dominated by a loss of small and large fiber function with little or no gain of function (deafferentation/sensory loss cluster). A similar approach relates to individual patient symptoms using patient reported outcome measures, i.e., neuropathic pain specific questionnaires. This phenotypic-based subgrouping has proven to be a promising approach to prospectively identify responders to a certain therapy, potentially realizing the concept of a new, individualized mechanism-based pain therapy.KeywordsStratificationQuantitative sensory testingDeafferentationIrritable nociceptorMechanism-based therapy
Pain is a leading symptom of numerous diseases across all clinical specialties. According to the current definition of the Neuropathic Pain Special Interest Group of the International Association for the Study of Pain, neuropathic pain is the direct consequence of damage to or disease of somatosensory nerve structures in the peripheral or central nervous system. According to the location of the lesion, a distinction is made between peripheral and central neuropathic pain, whereby mixed forms are not infrequently encountered in the chronic course of pain. From a pathophysiological point of view, it is also true that every pain condition – regardless of the cause – can result in structural and functional changes in pain-conducting, pain-processing and pain-controlling parts of the nervous system as a function of duration and intensity. These phenomena of peripheral and central sensitization are summarized as wind-up. The result is pain that becomes increasingly neuropathic over time and increasingly refractory to conventional therapies. Thus, neuropathic pain components can occur in any chronic pain process with corresponding negative consequences in terms of disease severity and treatability. This circumstance was taken into account with the introduction of the mixed pain concept, e.g. for chronic musculoskeletal pain conditions, and with a multiple revision of the definition and grading system of neuropathic pain, including secondary neuropathic pain conditions.
Background: Time elapsed since pain onset might affect the likelihood of neuropathic component in low back pain. The aim of this study was to investigate the relationship between neuropathic pain component and pain duration in patients with low back pain and to identify factors associated with neuropathic pain component. Methods: Patients with low back pain who received treatment at our clinic were enrolled. Neuropathic component was assessed using the painDETECT questionnaire at the initial visit. PainDETECT scores and the results for each item were compared according to pain duration category (< 3 months, 3 months to 1 year, 1 year to 3 years, 3 years to 10 years, and ≥ 10 years). A multivariate analysis was used to identify factors associated with neuropathic pain component (painDETECT score ≥13) in low back pain. Results: A total of 1957 patients, including 255 patients who reported neuropathic-like pain symptoms (13.0%), fully satisfied the study criteria for analysis. No significant correlation between painDETECT score and pain duration was observed (ρ= -0.025, p=0.272), and there were no significant differences between median painDETECT score or trend of change in the proportion of patients with neuropathic component and the pain duration category (p=0.307, p=0.427, respectively). The electric shock-like pain symptom was frequently reported in patients with acute low back pain, and the persistent pain pattern with slight fluctuations was predominant in chronic low back pain. The pattern of attacks with pain between them was much less common in patients with pain for 10 years or longer. Multivariate analysis revealed that a history of lumbar surgery, severe maximum pain, opioid use, lumbosacral radiculopathy, and sleep disturbance were significantly associated with a neuropathic component in low back pain. Conclusion: Time elapsed since current pain onset did not correlate with neuropathic pain component in patients with low back pain. Therefore, diagnostic and therapeutic approaches for this condition should be based on a multidimensional evaluation at assessment and not on pain duration alone.
Objectives The mechanism underlying neuropathic pain (NP) in osteoarthritis (OA) of the knee is not completely understood. This study aimed to investigate whether possible NP in patients with knee OA undergoing knee surgery is associated with specific radiological findings. Methods This study included 197 patients who underwent knee surgery for symptomatic knee OA. Clinical evaluation was performed using the Central Sensitization Inventory (CSI), Western Ontario and McMaster Universities Arthritis Index (WOMAC), and PainDETECT questionnaire. Radiological evaluation was performed using the hip-knee-ankle (HKA) angle, posterior tibial slope (PTS), varus and valgus laxities, and magnetic resonance imaging OA Knee Score (MOAKS). Radiological findings were compared between patients with possible and unlikely NP. Logistic regression analysis was performed to identify the predictive factors for NP. Results There were 163 and 34 patients with unlikely NP and with possible NP, respectively. The percentage of patients with CSI score ≥ 40 was significantly higher in the possible NP group than in the unlikely NP group (17.6% vs. 6.1%). Patients with possible NP had worse WOMAC scores than patients with unlikely NP. There were no significant positive associations between the possible NP and radiological findings in knee OA. Regression analysis showed no predictive factors for possible NP. Conclusions Possible NP is not associated with specific radiological findings in knee OA. Patients with possible NP may mediate CS and experience more severe symptoms, including decreased knee function and lower quality of life, than patients with unlikely NP.
Background and purpose: The description of pain is the most-important indicator leading to the adequate treatment of patients with neuropathic pain (NeP). The purpose of this study was to identify and characterize the unique features of Korean verbal descriptions in patients with peripheral NeP. Methods: This study included 400 patients (167 males and 233 females) and their 1,387 paindescription responses. Patients with peripheral NeP freely described their symptoms in Korean. Collected verbal descriptions were grouped according to terminologies with similar meanings. Participants completed validated patient-reported outcome scales including the neuropathic pain symptom inventory (NPSI) and painDETECT questionnaire (PD-Q). The frequencies of each verbal pain descriptor were compared between the NPSI and PD-Q scores. Results: 'Jeorim' (tingling) was the most common among 17 types of organized verbal pain descriptors, and the 'Sirim' (cold) symptom had a significantly higher rate of use in the 2 high-severity groups when participants were classified by their total scores on the NPSI and PD-Q. Conclusions: Korean verbal NeP descriptors were significantly diverse. The Jeorim (tingling) and Sirim (cold) descriptors can be utilized in evaluations of Korean patients with NeP.
Full-text available
This study describes the development and validation of a novel tool for identifying patients in whom neuropathic mechanisms dominate their pain experience. The Leeds assessment of neuropathic symptoms and signs (LANSS) Pain Scale is based on analysis of sensory description and bedside examination of sensory dysfunction, and provides immediate information in clinical settings. It was developed in two populations of chronic pain patients. In the first (n = 60), the use of sensory descriptors and questions were compared in patients with nociceptive and neuropathic pain, combined with an assessment of sensory function. This data was used to derive a seven item pain scale, consisting of grouped sensory description and sensory examination with a simple scoring system. The LANSS Pain Scale was validated in a second group of patients (n = 40) by assessing discriminant ability, internal consistency and agreement by independent raters. Clinical and research applications of the LANSS Pain Scale are discussed.
Different pathophysiological mechanisms are thought to operate in chronic sciatica. Nociceptive and neuropathic pain components can be distinguished. Neuropathic pain may be caused by lesions of nociceptive sprouts within the degenerated disc (local neuropathic), mechanical compression of the nerve root (mechanical neuropathic root pain), or by action of inflammatory mediators (inflammatory neuropathic root pain) originating from the degenerative disc even without any mechanical compression. Since different pain-generating mechanisms possibly underlie sciatic pain, the term mixed pain syndrome was established. The incidence of each pain component in chronic sciatica as well as validated diagnostic tools to identify them remain unknown. Current analgesic therapeutic first-line strategies for chronic sciatica rely on NSAIDs that are known to relieve nociceptive pain only. In neuropathic pain, different therapeutic approaches are effective, i.e., antidepressants such as amitriptyline and anticonvulsants such as gabapentin, carbamazepine, and pregabalin. Therefore, the combination of these analgesic compounds with NSAID could be useful in patients with sciatic pain who do not respond to NSAID.
In September 2001, a Task Force was set up under the auspices of the European Federation of Neurological Societies with the aim of evaluating the existing evidence about the methods of assessing neuropathic pain and its treatments. This review led to the development of guidelines to be used in the management of patients with neuro-pathic pain. In the clinical setting a neurological examination that includes an accurate sensory examination is often sufficient to reach a diagnosis. Nerve conduction studies and somatosensory-evoked potentials, which do not assess small fibre function, may demonstrate and localize a peripheral or central nervous lesion. A quantitative assessment of the nociceptive pathways is provided by quantitative sensory testing and laser-evoked potentials. To evaluate treatment efficacy in a patient and in controlled trials, the simplest psychometric scales and quality of life measures are probably the best methods. A laboratory measure of pain that by-passes the subjective report, and thus cognitive influences, is a hopeful aim for the future.
This paper describes conceptual and clinimetric aspects as well as fields of application of the Hannover Functional Ability Questionnaire for measuring back pain-related disability (FFbH-R). The FFbH-R belongs to a series of short self-administered questionnaires for the assessment of functional limitations in activities of daily living among patients with musculoskeletal disorders. In addition to the FFbH-R, a specific version is available for patients with polyarticular diseases (the FFbH-P), as well as a combined version of both questionnaires. A new questionnaire for patients with osteoarthritis is currently being developed. Data from various studies indicate that the FFbH-R meets the relevant psychometric criteria of acceptability, reliability, validity, and sensitivity to change. It has been successfully applied in (observational and controlled) clinical studies, in epidemiologic surveys, and in compensation disability evaluation.
Neuropathic pain syndromes are commonly seen in clinical practice and are frequently used as pain models in testing new therapies. However, no pain scale exists with the primary purpose to measure pain in neuropathic syndromes. This paper describes the development and preliminary validation of the Neuropathic Pain Scale (NPS), which is designed to assess distinct pain qualities associated with neuropathic pain. Results support the discriminant and predictive validity of the NPS items. Moreover, the NPS items appear to be sensitive to treatments known to impact neuropathic pain. These findings provide support for the further development of the NPS.
The goals of this study were to examine agreement and estimate differences in sensitivity between pain assessment scales. Multiple simultaneous pain assessments by patients in acute pain after oral surgery were used to compare a four-category verbal rating scale (VRS-4) and an 11-point numeric rating scale (NRS-11) with a 100-mm visual analog scale (VAS). The sensitivity of the scales (i.e., their ability [power] to detect differences between treatments) was compared in a simulation model by sampling from true pairs of observations using varying treatment differences of predetermined size. There was considerable variability in VAS scores within each VRS-4 or NRS-11 category both between patients and for repeated measures from the same patient. Simulation experiments showed that the VAS was systematically more powerful than the VRS-4 in all simulations performed. The sensitivity of the VAS and NRS-11 was approximately equal. In this acute pain model, the VRS-4 was less sensitive than the VAS. The simulation results demonstrated similar sensitivity of the NRS-11 and VAS when comparing acute postoperative pain intensity. The choice between the VAS and NRS-11 can thus be based on subjective preferences.
Ongoing efforts to develop mechanisms-based assessment and treatment of chronic pain have been hindered by the lack of assessment tools differentially sensitive to various phenomena underlying different mechanisms of pain. This study describes the development of an assessment instrument intended to measure neuropathic pain based on qualities of pain as they are inferred from pain descriptors. Subjects were 528 chronic pain patients from several clinics. Of these, 149 had strictly neuropathic pain, while 233 had non-neuropathic pain. Subjects completed a 32 item preliminary questionnaire, which asked them to rate their usual pain on multiple descriptors, as well as the degree to which their pain differed in response to various internal and external factors. This preliminary questionnaire was submitted to factor analysis, and this yielded 6 factors. Representatives of each of these factors were combined with additional items that demonstrated significant differences between neuropathic and non-neuropathic pain groups, to yield a 12 item Neuropathic Pain Questionnaire (NPQ). These items were able to differentiate neuropathic pain patients from non-neuropathic pain patients in a holdout sample with 66.6% sensitivity and 74.4% specificity. The newly developed instrument, NPQ, may be used for the initial screening of neuropathic pain patients. It also has the ability to provide a quantitative measure for the descriptors important in the diagnosis and assessment of neuropathic pain. Consequently, it can be used for monitoring of neuropathic pain treatments and as an outcome measure.