Fibromyalgia: A Disorder of the Brain?

P Schweinhardt, KM. Sauro, MC Bushnell

This article presents evidence that fibromyalgia patients have alterations in CNS anatomy, physiology, and chemistry that potentially contribute to the symptoms experienced by these patients. There is substantial psychophysical evidence that fibromyalgia patients perceive pain and other noxious stimuli differently than healthy individuals and that normal pain modulatory systems, such as diffuse noxious inhibitory control mechanisms, are compromised in fibromyalgia. Furthermore, functional brain imaging studies revealing enhanced pain-related activations corroborate the patients’ reports of increased pain. Neurotransmitter studies show that fibromyalgia patients have abnormalities in dopaminergic, opioidergic, and serotoninergic systems. Finally, studies of brain anatomy show structural differences between the brains of fibromyalgia patients and healthy individuals. The cerebral alterations offer a compelling explanation for the multiple symptoms of fibromyalgia, including widespread pain and affective disturbances. The frequent comorbidity of fibromyalgia with stress-related disorders, such as chronic fatigue, posttraumatic stress disorder, irritable bowel syndrome, and depression, as well as the similarity of many CNS abnormalities, suggests at least a partial common substrate for these disorders. Despite the numerous cerebral alterations, fibromyalgia might not be a primary disorder of the brain but may be a consequence of early life stress or prolonged or severe stress, affecting brain modulatory circuitry of pain and emotions in genetically susceptible individuals

NEUROSCIENTIST 14(5):415—421, 2008 (abstract only)

DOI: 10.1177/1073858407312521

Chronic Back Pain Is Associated with Decreased Prefrontal and Thalamic Gray Matter Density

Apkarian AV, Sosa Y, Sonty S, Levy RM, Harden RN, Parrish TB, Gitelman DR.

The role of the brain in chronic pain conditions remains speculative. We compared brain morphology of 26 chronic back pain (CBP) patients to matched control subjects, using magnetic resonance imaging brain scan data and automated analysis techniques. CBP patients were divided into neuropathic, exhibiting pain because of sciatic nerve damage, and non-neuropathic groups. Pain-related characteristics were correlated to morphometric measures. Neocortical gray matter volume was compared after skull normalization. Patients with CBP showed 5-11% less neocortical gray matter volume than control subjects. The magnitude of this decrease is equivalent to the gray matter volume lost in 10-20 years of normal aging. The decreased volume was related to pain duration, indicating a 1.3 cm3 loss of gray matter for every year of chronic pain. Regional gray matter density in 17 CBP patients was compared with matched controls using voxel-based morphometry and nonparametric statistics. Gray matter density was reduced in bilateral dorsolateral prefrontal cortex and right thalamus and was strongly related to pain characteristics in a pattern distinct for neuropathic and non-neuropathic CBP. Our results imply that CBP is accompanied by brain atrophy and suggest that the pathophysiology of chronic pain includes thalamocortical processes.

The Journal of Neuroscience, November 17, 2004, 24(46):10410-10415;

Full text PDF

doi:10.1523/JNEUROSCI.2541-04.2004

Stress-induced Physiologic Changes as a Basis for the Biopsychosocial Model of Chronic Musculoskeletal Pain: A New Theory?

Finestone, Hillel M; Alfeeli, Aziz MBChB; Fisher, William A.

Objectives: (1) To integrate the scientific literatures of the biopsychosocial model of chronic musculoskeletal pain and of stress-induced physiologic wound and muscle changes, and (2) to propose a clinical assessment and treatment model that incorporates this dual literature into the management of chronic musculoskeletal pain.

Methods: English language literature search from January 1990 to February 2008 using the MEDLINE and PsycINFO databases and the keywords “wound healing,” “musculoskeletal injury,” “skeletal muscle injury,” “psychological,” “social,” “stress,” “anxiety,” and “pain.”

Results: An illustrative case report is introduced. Review of the scientific literature revealed that psychologic stress is associated with slower or delayed wound healing in stressed older adults, restrained mice, socially isolated hamsters, adults with leg wounds, and surgical patients. One study showed that expressive writing positively affected the healing of a small skin puncture. Psychosocial stress affected aspects of muscle activity and spinal loading. Slaughter studies demonstrated that high preslaughter stress in pigs negatively affected postslaughter meat quality. A clinical model for the treatment of selected patients with painful musculoskeletal symptoms is offered.

Discussion: Important links exist between psychologic and social factors and recovery from insults to the “soft tissues.” Identifiable biochemical and physiologic processes mediate this relationship. It is time to rethink and refine views of the role of psychologic and social factors in musculoskeletal illness, chronicity, and pain.

The Clinical Joiurnal of Pain, Volume 24(9), November/December 2008, pp 767-775 – abstract

Full text available in through MTABC member only website under the research tab and then library.

Fibromyalgia Can No Longer Be Called the “Invisible” Syndrome

Using single photon emission computed tomography (SPECT), researchers in France were able to detect functional abnormalities in certain regions in the brains of patients diagnosed with fibromyalgia, reinforcing the idea that symptoms of the disorder are related to a dysfunction in those parts of the brain where pain is processed.

Clinical Correlate of Brain SPECT Perfusion Abnormalities in Fibromyalgia

E Guedj, S Cammilleri, J Niboyet, P Dupont et al

The purpose of this study was to investigate the specific clinical correlate of brain SPECT perfusion abnormalities reported in fibromyalgia.

Methods:We performed a whole-brain voxel-based correlation analysis involving regional cerebral blood flow and various parameters related to pain (Visual Analog Scale, Tubingen Pain Behavior Scale, and Questionnaire Douleur de Saint-Antoine Scale), disability (Fibromyalgia Impact Questionnaire
[FIQ]), and anxiety and depression status (Hospital Anxiety and Depression scale) in 20 patients with fibromyalgia (P voxel, 0.005). Ten healthy control women were also included, in order to determine areas of significant hypo- and hyperperfusions in patients.

Results: FIQ total score was positively correlated with bilateral parietal perfusion, including postcentral cortex. These clusters of correlation were included in the areas of significant hyperperfusion. FIQ total score was also negatively correlated with perfusion of a left anterior temporal cluster, included in the areas of significant hypoperfusions. No other clinical correlation was observed with regional cerebral blood flow.

Conclusion: These results show that brain perfusion abnormalities in patients with fibromyalgia are correlated with the clinical severity of the disease.
The Journal of Nuclear Medicine 2008; 49:1798–1803

Ful text PDF
DOI: 10.2967/jnumed.108.053264

A Distinct Pattern of Myofascial Findings in Patients After Whiplash Injury

Ettlin T, Schuster C, Stoffel R, Brüderlin A and Kischka U

Objective: To identify objective clinical examinations for the diagnosis of whiplash syndrome, whereby we focused on trigger points. Design: A cross-sectional study with 1 measurement point. Setting: A quiet treatment room in a rehabilitation center. Participants: Patients (n=124) and healthy subjects (n=24) participated in this study. Among the patient group were patients with whiplash-associated disorders (n=47), fibromyalgia (n=21), nontraumatic chronic cervical syndrome (n=17), and endogenous depression (n=15). Main Outcome Measure: Each patient and control subject had a manual examination for trigger points of the semispinalis capitis, trapezius pars descendens, levator scapulae, scalenus medius, sternocleidomastoideus, and masseter muscles bilaterally.
Results: Forty (85.1%) of the patients with whiplash had positive trigger points in the semispinalis capitis muscle. The patients with whiplash had a significantly higher prevalence of positive trigger points in the semispinalis capitis muscle than any of the control groups (P<.05). For the other examined muscles, the prevalence of trigger points in the patients with whiplash did not differ significantly from the patients with fibromyalgia or nontraumatic chronic cervical syndrome. It did differ from the patients with endogenous depression and the healthy controls.
Conclusions: Patients with whiplash showed a distinct pattern of trigger point distribution that differed significantly from other patient groups and healthy subjects. The semispinalis capitis muscle was more frequently affected by trigger points in patients with whiplash, whereas other neck and shoulder muscles and the masseter muscle did not differentiate between patients with whiplash and patients with nontraumatic chronic cervical syndrome or fibromyalgia.

Archives of Physical Medicine and Rehabilitation, Volume 89, Issue 7, July 2008, Pages 1290-1293

doi:10.1016/j.apmr.2007.11.041

Pain and Stress in a Systems Perspective: Reciprocal Neural, Endocrine, and Immune Interactions

CR Chapman, RP Tuckett and CW Song

Abstract

This paper advances a psychophysiological systems view of pain in which physical injury, or wounding, generates a complex stress response that extends beyond the nervous system and contributes to the experience of pain. Through a common chemical language comprising neurotransmitters, peptides, endocannabinoids, cytokines, and hormones, an ensemble of interdependent nervous, endocrine, and immune processes operates in concert to cope with the injury. These processes act as a single agent and comprise a supersystem. Acute pain in its multiple dimensions, and the related symptoms that commonly occur with it, are products of the supersystem. Chronic pain can develop as a result of unusual stress. Social stressors can compound the stress resulting from a wound or act alone to dysregulate the supersystem. When the supersystem suffers dysregulation, health, function, and sense of well-being suffer. Some chronic pain conditions are the product of supersystem dysregulation. Individuals vary and are vulnerable to dysregulation and dysfunction in particular organ systems due to the unique interactions of genetic, epigenetic and environmental factors, as well as the past experiences that characterize each person.

Perspective

Acute tissue injury activates an ensemble of interdependent nervous, endocrine, and immune processes that operate in concert and comprise a supersystem. Some chronic pain conditions result from supersystem dysregulation. Individuals vary and are vulnerable to dysregulation due to the unique interactions of genetic, epigenetic, and environmental factors and past experiences that characterize each person. This perspective can potentially assist clinicians in assessing and managing chronic pain patients.

The Journal of Pain, Vol 9, Issue 2, Feb 2008, Pages 122-145

doi:10.1016/j.jpain.2007.09.006

Expertise Modulates the Perception of Pain in Others

Yawei Cheng, Ching-Po Lin and Ho-Ling Liu et al

Perceiving the pain of others activates a large part of the pain matrix in the observer. Because this shared neural representation can lead to empathy or personal distress, regulatory mechanisms must operate in people who inflict painful procedures in their practice with patient populations in order to prevent their distress from impairing their ability to be of assistance. In this functional magnetic resonance imaging MRI study, physicians who practice acupuncture were compared to naive participants while observing animated visual stimuli depicting needles being inserted into different body parts, including the mouth region, hands, and feet. Results indicate that the anterior insula somatosensory cortex, periaqueducal gray, and anterior cingulate cortex were significantly activated in the control group, but not in the expert group, who instead showed activation of the medial and superior prefrontal cortices and the temporoparietal junction, involved in emotion regulation and theory of mind.

Current Biology, Vol 17, 1708-1713, 09 October 2007

Journal abstract

doi:10.1016/j.cub.2007.09.020