BACKGROUND: Cross-informant variance is often observed in patient self-reports versus parent proxy reports of pediatric chronic pain and disability.OBJECTIVE: To assess the relationship and merit of the child versus parent perspective.METHODS: A total of 99 patients (eight to 17 years of age [mean 13.2 years]; 71&#x25; female, 81&#x25; Caucasian) and parents completed the Pediatric Pain Questionnaire and Functional Disability Inventory at their initial clinic visit. Patients&#x2019; and parents&#x2019; pain intensity and disability scores were analyzed using an intraclass correlation coefficient (ICC), Wilcoxon signed-rank test, Bland-Altman plot and Spearman&#x2019;s correlation coefficient. The association between clinical/demographic variables and differences in patient/parent pain intensity and disability scores was assessed using multivariable regression.RESULTS: There was significant agreement between patients&#x2019; self-reports and parents&#x2019; proxy reports of their child&#x2019;s pain intensity (ICC=0.52; P&#x3c;0.001) and disability (ICC=0.57; P=0.004) at the individual level. There were no significant group differences in patient versus parent-proxy pain intensity scores (P=0.40) and disability scores (P=0.54). The difference between patient and parent-proxy pain intensity was associated with patients&#x2019; self-reported pain intensity (P&#x3c;0.001). The difference between patient and parent-proxy disability was associated with patient&#x2019;s self-reported pain disability (P&#x3c;0.001). Bland-Altman plots revealed major inter-rater variation in the Pediatric Pain Questionnaire and Functional Disability Inventory across their score ranges. A significant relationship (r=0.38; P&#x3c;0.001) was observed between patients&#x2019; self-reported pain intensity and disability.CONCLUSIONS: While equal merit should ideally be given to pediatric chronic pain patients&#x2019; self-reports and their parents&#x2019; proxy reports of pain intensity and disability, it would appear that, as needed, pediatric patients or parents can offer a clinically valid, single clinical perspective.

Thomas R Vetter

Cynthia L Bridgewater

Lee I Ascherman

Avi Madan-Swain

Gerald L McGwin

Patient Versus Parental Perceptions about Pain and Disability in Children and Adolescents with a Variety of Chronic Pain Conditions

BACKGROUND: Dynamic mechanical allodynia is traditionally induced by manual brushing of the skin. Brushing force and speed have been shown to influence the intensity of brush-evoked pain. There are still limited data available with respect to the optimal stroke number, length, force, angle and speed. Therefore, an automated brushing device (ABD) was developed, for which brushing angle and speed could be controlled to enable quantitative assessment of dynamic mechanical allodynia.OBJECTIVES: To compare the ABD with manual brushing using capsaicin-induced allodynia, and to investigate the role of stroke angle and speed on pain intensity.METHODS: Experimental dynamic mechanical allodynia was induced by an intradermal injection of capsaicin (100 &#x3bc;g) into the volar forearm of 12 healthy, male volunteers. Dynamic mechanical allodynia was rated on a 10 cm visual analogue scale (VAS) after each set of strokes at angles of 30&#xb0;, 60&#xb0; and 90&#xb0; with speeds of 17 mm/s, 21 mm/s and 25 mm/s for each angle. A two-way ANOVA with repeated measures was performed to assess the influence of brushing parameters. To evaluate test-retest reliability, Bland-Altman 95&#x25; limits of agreement, including a coefficient of repeatability and an intraclass correlation coefficient (ICC), were determined.RESULTS: The angle and speed exhibited a significant impact on pain intensity (P&#x3c;0.001 and P&#x3c;0.015, respectively). Post hoc analysis showed that the highest pain intensity was recorded with an angle of 30&#xb0; regardless of brushing speed. The ABD demonstrated superior test-retest reliability (coefficient of repeatability = 1.9 VAS; ICC=0.91) compared with manual brushing (coefficient of repeatability = 2.8 VAS; ICC=0.80; P&#x3c;0.05). The most reliable combination of parameters (coefficient of repeatability = 1.3 VAS; ICC=0.97) was an angle of 60&#xb0; and a speed of 21 mm/s.CONCLUSIONS: A controlled, automatic brushing method can be used for quantitative investigations of allodynic reactions, and is more reliable for quantitative assessment of dynamic mechanical allodynia compared with traditional manual brushing.

Kristian G du Jardin

Lise S Gregersen

Turid R&#xf8;sland

Kathrine H Uggerh&#xf8;j

Lars J Petersen

Lars Arendt-Nielsen

Parisa Gazerani

Assessment of Pain Response in Capsaicin-Induced Dynamic Mechanical Allodynia Using a Novel and Fully Automated Brushing Device

Robert B Kalina

Changes

Long term administration of an opioid drug for chronic nonmalignant pain continues to be controversial, but is no longer uniformly rejected by pain specialists. This is true despite concerns that the regulatory agencies that oversee physician prescribing of opioid drugs continue to stigmatize the practice. The changing clinical perspective has been driven, in part, by widespread acknowledgement of the remarkably favourable outcomes achieved during opioid treatment of cancer pain. These outcomes contrast starkly with popular teaching about chronic opioid therapy and affirm the potential for prolonged efficacy, tolerable side effects, enhanced function associated with improved comfort and minimal risk of aberrant drug-related behaviours consistent with addiction. A large anecdotal experience in populations with nonmalignant pain suggests that these patients are more heterogeneous and that opioid therapy will greatly benefit some and will contribute to negative outcomes for others. The few controlled clinical trials that have been performed support the safety and efficacy of opioid therapy, but have been too limited to ensure generalization to the clinical setting. A critical review of the medical literature pertaining to chronic pain, opioid pharmacology and addiction medicine can clarify misconceptions about opioid therapy and provide a foundation for patient selection and drug administration. The available data support the view that opioids are no panacea for chronic pain, but should be considered in carefully selected patients using clinically derived guidelines that stress a structured approach and ongoing monitoring of efficacy, adverse effects, functional outcomes and the occurrence of aberrant drug-related behaviours.

Russell K Portenoy

Opioid Therapy for Chronic Nonmalignant Pain

BACKGROUND: Both excitatory and inhibitory amino acids modulate central neuronal activity following peripheral nerve tissue injury.OBJECTIVE: To establish whether mononeuropathy induced by chronic constriction injury or by sectioning of the sciatic nerve affects neurotransmitter amino acid levels in the rat brain areas.METHODS: Glutamine, glutamic acid, gamma-aminobutyric acid (GABA) and aspartic acid in the hindbrain, midbrain and hypothalamus of rats were measured by high performance liquid chromatography 14 days after surgery.RESULTS: After monolateral nerve ligation an increase in glutamine and a decrease in GABA levels in all brain areas were observed, with no side preference. The section of the sciatic nerve did not cause any modification in amino acid levels.CONCLUSIONS: The results allow one to differentiate more clearly classic models of mononeuropathy from a biochemical point of view. Moreover, results indicate that continuous neuronal stimulation induced by nerve constriction is able to modify some amino acid pathways at a supraspinal level.

Mauro Bianchi

Paolo Ferrario

Antonio Clavenna

Gabriele Biella

Maria Luisa Sotgiu

Amino Acid Levelsin the Brain of Rats with Peripheral Nerve Constriction or Section

Kenneth D Craig

Appreciation and Future Prospects

We take pleasure in this issue in presenting a series of plenary session lectures and some additional contributions from the Bern Symposium, a meeting held in Berne, Switzerland from March 8 to 10, 2001. The symposium was organized by Dr Bogdan Radanov and colleagues from that city where they had themselves undertaken an enormous amount of classical work in the investigation of cervical sprain syndrome. Radanov's work resolved a number of definitive issues in the investigation of whiplash, despite those who say otherwise for medicolegal reasons. He and his colleagues showed clearly that pain after cervical sprain injury was primarily correlated with the intensity of the initial pain, with the occurrence of premorbid injury and with age. Personality status before injury had no bearing on the outcome, and the intensity of pain at the beginning of injury was also correlated with depression or cognitive change later (1).

Harold Merskey

International Congress on Whiplash Associated Disorders - The Bern Symposium

The Expanding Universe of Pain Research &#x26; Management

George V Rossie

R Daun Gretzinger

Toward making 'IMEs' Independent

Clinicians often encounter patients who present with both chronic pain and elevated levels of anxiety. In some cases, the source of the anxiety is vague and diffuse. For others, there is an identifiable precipitating object, event or situation. For example, some patients with chronic pain are able to attribute their anxiety to the possibility of not regaining lost functional abilities, financial difficulties, feelings of social inadequacy, or uncertainty about the meaning and consequences of pain. The association between chronic pain and anxiety may not be particularly surprising when one considers that, in the acute phase, both pain and target-oriented anxiety (or fear) motivate actions that serve to minimize the threat and maximize the likelihood of successful escape. As well, their neurobiology, while distinct, interacts in the reticular system (1). Evaluations of the association between chronic pain and fear-relevant constructs were initiated in the 1960s and 1970s (2,3). It has only been of late, however, that theorists and researchers have begun to focus their attention on delineating the precise nature of the relationship and its specific implications for the assessment and management of pain.

Gordon JG Asmundson

Anxiety and Related Factors in Chronic Pain

BACKGROUND: Facial expression is widely used to judge pain in neonates. However, little is known about the relationship between intensity of the painful stimulus and the nature of the expression in term neonates.OBJECTIVES: To describe differences in the movement of key facial areas between two groups of term neonates experiencing painful stimuli of different intensities.METHODS: Video recordings from two previous studies were used to select study subjects. Four term neonates undergoing circumcision without analgesia were compared with four similar male term neonates undergoing a routine heel stick. Facial movements were measured with a computer using a previously developed ‘point-pair’ system that focuses on movement in areas implicated in neonatal pain expression. Measurements were expressed in pixels, standardized to percentage of individual infant face width.RESULTS: Point pairs measuring eyebrow and eye movement were similar, as was the sum of change across the face (41.15 in the circumcision group versus 40.33 in the heel stick group). Point pair 4 (horizontal change of the mouth) was higher for the heel stick group at 9.09 versus 3.93 for the circumcision group, while point pair 5 (vertical change of the mouth) was higher for the circumcision group (23.32) than for the heel stick group (15.53).CONCLUSION: Little difference was noted in eye and eyebrow movement between pain intensities. The mouth opened wider (vertically) in neonates experiencing the higher pain stimulus. Qualitative differences in neonatal facial expression to pain intensity may exist, and the mouth may be an area in which to detect them. Further study of the generalizability of these findings is needed.

Martin Schiavenato

Meggan Butler-O’Hara

Paul Scovanner

Exploring the Association Between Pain Intensity and Facial Display in Term Newborns

About this journal

Pain Research and Management publishes research focusing on laboratory and clinical findings in the field of pain research and the prevention and management of pain.

Journal profile

Meet the editorial board

Chief Editor&nbsp;Professor Valeriani specialises in clinical neurophysiology with a particular interest in pain and headaches in children and adults, and is currently a neurologist who works at the Bambi Gesu Children’s Hospital in Rome.

Editor spotlight

Submit your proposal

Do you think there is an emerging area of research that really needs to be highlighted? Or an existing research area that has been overlooked or would benefit from deeper investigation? Raise the profile of a research area by leading a Special Issue.

Special Issues

Author guidelines

Editorial board

Databases and indexing

Pain Research and Management - Table of contents

title

Pain Research and Management publishes research focusing on laboratory and clinical findings in the field of pain research and the prevention and management of pain.

Pain Research and Management