Jule Frettlöh

Severity and specificity of neglect-like symptoms in patients with complex regional pain syndrome (CRPS) compared to chronic limb pain of other origins

Abstract In the literature, the neglect‐like syndrome is described as an additional phenomenon of CRPS. The perception of the affected limb as strange, disordered and not belonging to the body is typical of and characterises this syndrome. Since this phenomenon has never been studied in other pain conditions, we assessed occurrence and extent of neglect‐like symptoms in patients with CRPS of the upper and lower limb (n = 123) and in a control group with chronic limb pain of other origins (n = 117). Our questionnaire for describing the neglect‐like syndrome encompassed five items following Galer and Jensen [Galer BS, Jensen M. Neglect‐like symptoms in complex regional pain syndrome: results of a self‐administered survey. Journal of Pain and Symptom Management 1999;18:213–6], with a six‐point response scale inquiring the extent of respective symptoms. Results show that CRPS‐patients as well as patients with non‐CRPS limb pain exhibit the so‐called neglect‐like syndrome. However, the number of patients confirming such symptoms was significantly higher (OR = 2.87) in the CRPS group, moreover, these patients reported more severe symptoms (F = 17.74; p = 0.001). If the neglect‐like total score is ⩾5, the diagnostic sensitivity is low (21.1%), but the specificity for the diagnosis of CRPS reaches 90.6%. In this study, patients with CRPS of the upper and lower limb were included. The only difference between these two localisations concerning the neglect‐like syndrome was the symptom of ‘involuntary movements’, which occurs significantly more often in affected legs. In conclusion, we recommend to evaluate neglect‐like symptoms and to use them as an additional criterion in the diagnosis of CRPS. High scores of ⩾5 confirm the diagnosis of CRPS, whereas lower scores must not be used for disease classification.

Validation of the German Mainz Pain Staging System in different pain syndromes

Zusammenfassung.Fragestellung: In der vorliegenden Studie wird die Frage untersucht, ob die 3 Chronifizierungsstadien des Mainzer Stadienmodells der Schmerzchronifizierung (MPSS) bei verschiedenen Schmerzdiagnosegruppen mit Unterschieden in den Validitätsindikatoren „Schmerzempfindung“,„schmerzbezogene Beeinträchtigung“,„Depressivität“ und „Lebensqualität“ korrespondieren.Methodik: Der Analyse lagen konsekutiv erhobene Daten aus dem Dokumentationsprogramm QUAST zu Grunde. Validitätsindikatoren waren Selbstbeurteilungsangaben aus Testverfahren des Deutschen Schmerzfragebogens der DGSS. Die zentrale Auswertung erfolgte für Patienten mit der Hauptschmerzdiagnose „Kopfschmerz“, „neuropathischer Schmerz“, „Rückenschmerz“ und „muskuloskelettaler Schmerz“. Für jede der 4 Hauptdiagnosen wurde getrennt überprüft, ob sich die Patienten der 3 Chronifizierungsstadien in den Ausprägungen der psychometrischen Testverfahren unterscheiden und ob sich die 4 Diagnosegruppen untereinander unterscheiden.Ergebnisse: Es wurden 862 Datensätze in die diagnosespezifische Validitätsprüfung aufgenommen. Das Ausmaß der psychosozialen Beeinträchtigung steigt in allen 4 Diagnosegruppen in Abhängigkeit vom Chronifizierungsstadium an. Mit ansteigendem Chronifizierungsstadium steigt zudem der Anteil von Patienten mit Hinweis auf eine klinisch relevante Depression. Dies spricht für die diagnoseübergreifende Validität des MPSS.Schlussfolgerung: Die Befunde belegen für die 4 Diagnosegruppen eine gute Konstruktvalidität des Mainzer Stadienmodells. Da der Anteil der Patienten innerhalb eines Schmerzstadiums diagnoseabhängig ist, sollte auch in zukünftigen Untersuchungen, in denen das Chronifizierungsstadium als unabhängige Variable eingeht, die Auswertung getrennt nach Schmerzdiagnosegruppen erfolgen.Abstract.Objective: Our study was carried out to clarify whether differences in pain intensity,pain-related disability,depression and quality of life change with respect to the stage of chronicity of the Mainz Pain Staging Study (MPSS) in different pain syndromes. Keywords · · · · Methods: All patients with an initial pain clinic consultation from July 2000 to July 2001 and suffering from four major pain syndromes („headache“, „neuropathic pain“, „back pain“ or „muscle and joint pain“) were included. Indicators of validity were several self-rating scales from the German pain questionnaire of the German Chapter of the International Association for the Study of Pain (DGSS). Patient data were collected using QUAST, a database environment specifically developed for documentation and quality assurance in pain therapy. An assessment was made for each of the four major diagnoses to determine whether patients in the three chronicity stages differed in their psychometric test results. In addition,the four diagnosis groups were tested for differences from one another.Results: A total of 862 patient charts with documented pain syndromes and MPSS were extracted and analyzed. The extent of the subjective psychosocial stress and disability increased in all diagnosis groups and was correlated with the chronicity stage. The proportion of patients with an indication of clinically relevant depression (ADS score >23) increased with chronicity regardless of the pain diagnosis. The four main diagnosis groups differed with respect to the chronicity stage according to MPSS (P<0.001), with headache patients being classified predominantly as stage I. Patients with an additional pain diagnosis had a higher chronicity stage (P<0.001).Conclusion: Our results underline the validity of the MPSS for the four diagnosis groups examined; however, pain diagnosis must be controlled in all studies using chronicity stage as an independent variable, e.g., therapy studies. For optimal results physicians must closely follow the test instructions of the MPSS.

Left is where the L is right. Significantly delayed reaction time in limb laterality recognition in both CRPS and phantom limb pain patients.

The body schema is based on an intact cortical body representation. Its disruption is indicated by delayed reaction times (RT) and high error rates when deciding on the laterality of a pictured hand in a limb laterality recognition task. Similarities in both cortical reorganisation and disrupted body schema have been found in two different unilateral pain syndromes, one with deafferentation (phantom limb pain, PLP) and one with pain-induced dysfunction (complex regional pain syndrome, CRPS). This study aims to compare the extent of impaired laterality recognition in these two groups. Performance on a test battery for attentional performance (TAP 2.0) and on a limb laterality recognition task was evaluated in CRPS (n=12), PLP (n=12) and healthy subjects (n=38). Differences between recognising affected and unaffected hands were analysed. CRPS patients and healthy subjects additionally completed a four-day training of limb laterality recognition. Reaction time was significantly delayed in both CRPS (2278±735.7ms) and PLP (2301.3±809.3ms) compared to healthy subjects (1826.5±517.0ms), despite normal TAP values in all groups. There were no differences between recognition of affected and unaffected hands in both patient groups. Both healthy subjects and CRPS patients improved during training, but RTs of CRPS patients (1874.5±613.3ms) remain slower (p<0.01) than those of healthy subjects (1280.6±343.2ms) after four-day training. Despite different pathomechanisms, the body schema is equally disrupted in PLP and CRPS patients, uninfluenced by attention and pain and cannot be fully reversed by training alone. This suggests the involvement of complex central nervous system mechanisms in the disruption of the body schema.

Bilateral somatosensory cortex disinhibition in complex regional pain syndrome type I

Objective: In a previous study, we found bilateral disinhibition in the motor cortex of patients with complex regional pain syndrome (CRPS). This finding suggests a complex dysfunction of central motor-sensory circuits. The aim of our present study was to assess possible bilateral excitability changes in the somatosensory system of patients with CRPS. Methods: We measured paired-pulse suppression of somatosensory evoked potentials in 21 patients with unilateral CRPS I involving the hand. Eleven patients with upper limb pain of non-neuropathic origin and 21 healthy subjects served as controls. Innocuous paired-pulse stimulation of the median nerve was either performed at the affected and the unaffected hand, or at the dominant hand of healthy controls, respectively. Results: We found a significant reduction of paired-pulse suppression in both sides of patients with CRPS, compared with control patients and healthy control subjects. Conclusion: These findings resemble our findings in the motor system and strongly support the hypothesis of a bilateral complex impairment of central motor-sensory circuits in CRPS I.

Long-term skin temperature measurements : A practical diagnostic tool in complex regional pain syndrome

Abstract Despite the development of the IASP criteria, diagnosing complex regional pain syndrome (CRPS) remains a challenge because all symptoms vary interindividually, including the vascular abnormalities. Previous studies showed that skin temperature asymmetries between the affected and contralateral extremity around 2 °C are useful for diagnosing CRPS. However, they were either assessed only at one single point in time or during specific investigations including controlled thermoregulatory modulation of sympathetic activity which limits their practicability. The present study evaluated long‐term skin temperature changes under everyday circumstances in 22 patients with CRPS, 18 patients with limb pain of other origin and 23 healthy controls. The asymmetries in skin temperature and oscillation number (QOscill), the percentage of assessed time with a‐synchron temperature changes on both body sides and the determination coefficient of the individual regression (r2id) were compared between the groups. Patients with CRPS differed significantly from healthy controls in nearly all parameters. Minor differences between both patient groups were found regarding the percentage of assessed time with side difference >2 °C (ΔT2). However, both patient groups differed significantly in parameters characterizing the skin temperature dynamics. A sum score (2SymbolQOscill + r2id + ΔT2) allowed diagnosing CRPS with a specificity of 67% vs. patients with other painful diseases and 79% vs. healthy controls (sensitivity: 73%, respectively, 94%) and reflected the severity of the dysfunction in CRPS better than the mean skin temperature side differences alone. The applied skin temperature analysis can be easily applied in the clinical settings and serves as a further facet in the difficult diagnosis of CRPS. Symbol. No caption available.

Validität des Mainzer Stadienmodells der Schmerzchronifizierung bei unterschiedlichen Schmerzdiagnosen

Zusammenfassung.Fragestellung: In der vorliegenden Studie wird die Frage untersucht, ob die 3 Chronifizierungsstadien des Mainzer Stadienmodells der Schmerzchronifizierung (MPSS) bei verschiedenen Schmerzdiagnosegruppen mit Unterschieden in den Validitätsindikatoren „Schmerzempfindung“,„schmerzbezogene Beeinträchtigung“,„Depressivität“ und „Lebensqualität“ korrespondieren.Methodik: Der Analyse lagen konsekutiv erhobene Daten aus dem Dokumentationsprogramm QUAST zu Grunde. Validitätsindikatoren waren Selbstbeurteilungsangaben aus Testverfahren des Deutschen Schmerzfragebogens der DGSS. Die zentrale Auswertung erfolgte für Patienten mit der Hauptschmerzdiagnose „Kopfschmerz“, „neuropathischer Schmerz“, „Rückenschmerz“ und „muskuloskelettaler Schmerz“. Für jede der 4 Hauptdiagnosen wurde getrennt überprüft, ob sich die Patienten der 3 Chronifizierungsstadien in den Ausprägungen der psychometrischen Testverfahren unterscheiden und ob sich die 4 Diagnosegruppen untereinander unterscheiden.Ergebnisse: Es wurden 862 Datensätze in die diagnosespezifische Validitätsprüfung aufgenommen. Das Ausmaß der psychosozialen Beeinträchtigung steigt in allen 4 Diagnosegruppen in Abhängigkeit vom Chronifizierungsstadium an. Mit ansteigendem Chronifizierungsstadium steigt zudem der Anteil von Patienten mit Hinweis auf eine klinisch relevante Depression. Dies spricht für die diagnoseübergreifende Validität des MPSS.Schlussfolgerung: Die Befunde belegen für die 4 Diagnosegruppen eine gute Konstruktvalidität des Mainzer Stadienmodells. Da der Anteil der Patienten innerhalb eines Schmerzstadiums diagnoseabhängig ist, sollte auch in zukünftigen Untersuchungen, in denen das Chronifizierungsstadium als unabhängige Variable eingeht, die Auswertung getrennt nach Schmerzdiagnosegruppen erfolgen.Abstract.Objective: Our study was carried out to clarify whether differences in pain intensity,pain-related disability,depression and quality of life change with respect to the stage of chronicity of the Mainz Pain Staging Study (MPSS) in different pain syndromes. Keywords · · · · Methods: All patients with an initial pain clinic consultation from July 2000 to July 2001 and suffering from four major pain syndromes („headache“, „neuropathic pain“, „back pain“ or „muscle and joint pain“) were included. Indicators of validity were several self-rating scales from the German pain questionnaire of the German Chapter of the International Association for the Study of Pain (DGSS). Patient data were collected using QUAST, a database environment specifically developed for documentation and quality assurance in pain therapy. An assessment was made for each of the four major diagnoses to determine whether patients in the three chronicity stages differed in their psychometric test results. In addition,the four diagnosis groups were tested for differences from one another.Results: A total of 862 patient charts with documented pain syndromes and MPSS were extracted and analyzed. The extent of the subjective psychosocial stress and disability increased in all diagnosis groups and was correlated with the chronicity stage. The proportion of patients with an indication of clinically relevant depression (ADS score >23) increased with chronicity regardless of the pain diagnosis. The four main diagnosis groups differed with respect to the chronicity stage according to MPSS (P<0.001), with headache patients being classified predominantly as stage I. Patients with an additional pain diagnosis had a higher chronicity stage (P<0.001).Conclusion: Our results underline the validity of the MPSS for the four diagnosis groups examined; however, pain diagnosis must be controlled in all studies using chronicity stage as an independent variable, e.g., therapy studies. For optimal results physicians must closely follow the test instructions of the MPSS.

Local cytokine changes in complex regional pain syndrome type I (CRPS I) resolve after 6 months.

Summary Local cytokine changes were analyzed in CRPS I patients. TNF‐&agr;, MIP‐1&bgr;, and IL‐1RA were changed bilaterally but returned to the level of non‐CRPS patients after 6 months. Abstract There is evidence that inflammatory processes are involved in at least the early phase of complex regional pain syndrome (CRPS). We compared a panel of pro‐ and antiinflammatory cytokines in skin blister fluids and serum from patients with CRPS and patients with upper‐limb pain of other origin (non‐CRPS) in the early stage (< 1 year) and after 6 months of pain treatment. Blister fluid was collected from the affected and contralateral nonaffected side. We used a multiplex‐10 bead array cytokine assay and Luminex technology to measure protein concentrations of the cytokines interleukin‐1 receptor antagonist (IL‐1RA), IL‐2, IL‐6, IL‐8, IL‐10, IL‐12p40, and tumor necrosis factor‐alpha (TNF‐&agr;) and the chemokines eotaxin, monocyte chemotactic protein‐1 (MCP‐1), and macrophage inflammatory protein‐1&bgr; (MIP‐1&bgr;). We found bilaterally increased proinflammatory TNF‐&agr; and MIP‐1&bgr; and decreased antiinflammatory IL‐1RA protein levels in CRPS patients compared to non‐CRPS patients. Neither group showed side differences. After 6 months under analgesic treatment, protein levels of all measured cytokines in CRPS patients, except for IL‐6, significantly changed bilaterally to the level of non‐CRPS patients. These changes were not related to treatment outcome. In serum, only IL‐8, TNF‐&agr;, eotaxin, MCP‐1, and MIP‐1&bgr; were detectable without intergroup differences. Blister fluid of CRPS patients showed a bilateral proinflammatory cytokine profile. This profile seems to be relevant only at the early stage of CRPS. Almost all measured cytokine levels were comparable to those of non‐CRPS patients after 6 months of analgesic treatment and were not related to treatment outcome.

A modified score to identify and discriminate neuropathic pain: a study on the German version of the neuropathic pain symptom inventory (NPSI)

BackgroundNeuropathic pain must be correctly diagnosed for optimal treatment. The questionnaire named Neuropathic Pain Symptom Inventory (NPSI) was developed in its original French version to evaluate the different symptoms of neuropathic pain. We hypothesized that the NPSI might also be used to differentiate neuropathic from non-neuropathic pain.MethodsWe translated the NPSI into German using a standard forward-backward translation and administered it in a case-control design to patients with neuropathic (n = 68) and non-neuropathic pain (headache and osteoarthritis, n = 169) to validate it and to analyze its discriminant properties, its sensitivity to change, and to detect neuropathic pain subgroups with distinct profiles.ResultsUsing a sum score (the NPSI-G score), we found sensitivity to change (r between 0.37 and 0.5 for pain items of the graded chronic pain scale) and could distinguish between neuropathic and other pain on a group basis, but not for individual patients. Post hoc development of a discriminant score with optimized diagnostic properties to distinguish neuropathic pain from non-neuropathic pain resulted in an instrument with high sensitivity (91%) and acceptable specificity (70%). We detected six different pain profiles in the patient group with neuropathic pain; three profiles were found to be distinct.ConclusionsThe NPSI-G potentially combines the properties of a diagnostic tool and an instrument to identify subtypes of neuropathic pain.

Prevention of medication overuse in patients with migraine

&NA; This multi‐center study compared the therapeutic effect of a cognitive‐behavioral minimal contact program (MCT) to the effect of a brochure (bibliotherapy) for the prevention of medication overuse headache (MOH) in migraine patients. Seven German headache centers recruited 182 migraine patients with high triptan or analgesic intake frequency. Patients were randomly allocated to either the MCT‐group, receiving both an MCT program and an educational brochure or to the biblio‐group receiving only the brochure. All participants continued usual medical treatment. Course of headaches, intake of analgesics or triptans after training, 3 months post‐training as well as 1–2 years (mean 15.7 months) later and psychological variables were defined as outcome variables. A significant decline was observed in the number of headache days (11.0–8.8), migraine days (7.3–5.7) and medication intake days (7.4–6.1) from pre to post in the MCT‐group (p < 0.001 each) and in the biblio‐group (p < 0.001 each). The pre‐to‐post‐improvements were maintained from pre‐ to short‐ and from pre‐ to long‐term follow‐up (p < 0.001 each) in both groups. Both groups improved significantly from pre to post in psychological variables, e.g. pain acceptance: p < 0.001; pain catastrophizing: p < 0.001; functional pain coping: p < 0.001; and pain related internal control beliefs: p < 0.01. Psychological improvements remained stable in both groups at short‐ and long‐term follow‐up. During the study, none of the patients developed an MOH. MCT‐ and bibliotherapy are useful in migraine patients to prevent medication overuse headache or the transition of episodic to chronic headache.

Patientenkollektiv deutscher schmerztherapeutischer Einrichtungen

BACKGROUND In 1998 the board of the DGSS introduced a computerized documentation system named QUAST (quality assurance in pain therapy) building the foundation for a large, anonymous database that served as a data source for the statistical characterization of clinically relevant profiles of patients in German pain clinics. METHODS A total of 10,054 data files collected between 1998 and 2004, including socio-demographic as well as psychometric and pain parameters were analyzed. RESULTS The main pain diagnoses found in the database sample were back pain (37%), neuropathic pain (21.4%), soft tissue or arthralgia pain (19.5%) and headache (10.6%). The average duration of illness upon presentation at pain clinics was 7 years, nearly 20% contacted it within the first year. Of the sample, 43.8% of the patients were in the second chronicity stage and 39.0% in the third stage of the Mainz Pain Staging System (MPSS). Psychological measurements concerning despression, pain disability and quality of life indicated a great amount of psychological distress. Pronounced differences between main diagnostic groups were observed not only for psychological factors but also for direct pain parameters. CONCLUSIONS The documented data differ from other population-based data collections. In contrast to common belief there are a considerable number of patients who find access to specialized pain therapy institutions at an early stage of their illness. The hitherto regular use of generic, syndrome-overlapping diagnosis and treatment tools should be reconsidered taking into account the differences found between the main pain diagnosis groups. Lastly, this analysis provides current data on the psychological state of chronic pain patients showing a high degree of psychological distress and underlying the need of psychotherapeutic interventions in the treatment of chronic pain patients.