FM :: Fibromyalgia

FMS :: "Fibromyalgia Syndrome"

"Many fibromyalgia patients see an average of four physicians-over a duration of five to eight years after the onset of the disease-before an accurate diagnosis of fibromyalgia is achieved. This represents five to eight years of underdiagnosis, misdiagnosis and inappropriate treatment of the patient," said Victor Marrow, Ph.D., Executive Director, Office of Funded Programs/CME Johns Hopkins School of Medicine.

FM, Fibromyalgia is coded in the ICD-10 under M79.7
The coding is the same in both the WHO(online 2008) and the US(2007)
M79 Other soft tissue disorders, not elsewhere classified
Excludes1:psychogenic rheumatism (F45.8)
soft tissue pain, psychogenic (F45.4)
M79.0 Rheumatism, unspecified
Excludes: fibromyalgia ( M79.7 )
Excludes1:palindromic rheumatism (M12.3-)
M79.1 Myalgia
M79.6 Pain in limb
M79.7 Fibromyalgia
M79.8 Other specified soft tissue disorders
M79.9 Soft tissue disorder, unspecified

While in ICD-9 the only entry is for Fibrositis
729.0 Rheumatism, unspecified

Extracts from "Fibromyalgia Syndrome: Canadian Clinical Working Case Definition, Diagnostic and Treatment Protocols ­A Consensus Document" Jain et al.


Fibromyalgia syndrome [FMS] is a chronic disorder which has been defined by a history of widespread pain and the presence of marked tenderness to palpation at standard anatomically-defined tender points (1). The World Health Organization [WHO] incorporated fibromyalgia into their 10th revision of the International Classification of Diseases [ICD] in 1991 (2). They assigned fibromyalgia number M79.0 and classified it as a non-articular rheumatism. Fibro refers to fibrous tissues-­ligaments and tendons, myo refers to muscle, and algia refers to pain. Distinctive reproducible pain sites called "tender points" confirm the predominant feature of widespread musculoskeletal pain. In addition to the musculoskeletal manifestations, patients commonly exhibit recurrent headaches, persistent fatigue, sleep disturbances, neurocognitive, autonomic and neuroendocrine dysfunctions, and exercise intolerance. The symptoms of FMS are prolonged, can be debilitating, and in many patients they do not resolve over time.....more

In 1904, Dr. William Gowers, who was mainly concerned about a form of lumbago that he considered to be different from the standard back pain, coined the term "fibrositis" to describe pain associated with fibrous or connective tissue (3). In the 1960s, the meaning of fibrositis was expanded to include diffuse musculoskeletal pain, multiple site tenderpoints, poor sleep and fatigue (4). Heightened interest developed in the 1970s when Canadian researchers, Smythe and Moldofsky (5) demonstrated that the symptoms of fatigue and diffuse muscular pain correlated with specific changes on sleep electroencephalograms. As a result, criteria for clinical fibrositis were developed (6). Under the aegis of the American College of Rheumatology [ACR, see Appendix 1, p. 78], a large multi-center study was launched that resulted in the establishment of FMS criteria that had a clinical sensitivity of 88.4 percent and specificity of 81.1 percent. These criteria (1), which were published in 1990, have served an important function in the nosology of medicine resulting in a reliable body of comparative research data and growing recognition of fibromyalgia syndrome as a legitimate, discrete medical entity.

As the ACR definition was primarily created to standardize research, there has been a growing demand within the medical community for a clinical definition, which would be of benefit to the treating clinician. The consensus panel agreed that the ACR criteria had good sensitivity and specificity and was accepted worldwide. Based on the consensus panel's collective extensive clinical experience of diagnosing and/or treating more than twenty thousand [20,000] FMS patients, they concurred that for clinical purposes, it is important to include and put greater emphasis on the potential spectrum of other physiological dysfunctions, in addition to musculoskeletal pain, that can be intrinsic parts of this illness.

Our strategy for the clinical definition is to provide a flexible framework that includes the ACR criteria and encompasses more of the potential symptomatic expression of patients within the context of FMS. Grouping symptoms by shared regions of pathogenesis will enhance clarity and focus to the clinical meeting.


   A. Prevalence of FMS

The prevalence of FMS is likely underestimated as many cases are attributed to other systemic disorders or misdiagnosed as psychiatric in origin. A London, Ontario study (7) suggests that 3.3 percent of non-institutionalized adults are afflicted with FMS. Other studies suggest the prevalence is between 2 percent and 10 percent or 2,000 to 10,000 per 100,000 persons of the general population (8,9). In a prevalence study of randomly selected school children, 6.2 percent met the criteria for FMS (10). FMS is between two and five times more common than rheumatoid arthritis [RA] in the general population. As in many arthritic diseases, it predominantly affects females (8). FMS occurs most often between the ages of 35 and 50 years, but can affect all age groups.

B. Natural History of FMS

The natural history of FMS was prospectively monitored for up to eight years in a multi-center study (11). Patients completed self-assessment questionnaire forms to repeatedly quantify the severity of their pain, functional status, and affective symptoms. In general, the findings indicated that once the disorder was established, the patients continued to be symptomatic and did not improve over that period of time. Functional disability worsened slightly.

In a follow-up study of thirty-nine patients, Kennedy and Felson found that all patients still had fibromyalgia fifteen years later. Sixty-six percent indicated that they had some improvement but 59 percent had notable fatigue, 55 percent had moderate to severe pain and/or stiffness and 48 percent had reported significant sleep difficulties (12). It should be noted that chronic sleep loss [< 7 hours per night] may shorten longevity (13).
Statistical studies estimate group prognosis. However, individual prognosis must remain a clinical estimate and is highly variable. The clinician must ascertain the severity and course of the patients' illness and impairments, as well as the patients' circumstances, environment, and the life-world to which they are responding.

C. Costs of FMS

As FMS is two to five times more common than RA (8), the approximate anticipated cost for FMS is at least double the overall direct medical cost for RA. There are important dif- ferences between FMS and RA that should be noted. Lacking the inflammation of RA, primary FMS are not expected to show the same degree of joint destruction and to require the very costly total joint arthroplasties that are often needed by the RA patient with aggressive erosive disease.

Evidence from a multi-center study conducted in the United States (14) and a single center study in Canada (15) has assessed the direct medical costs of fibromyalgia syndrome to patients and to the general economy. The findings indicated that the annual direct medical cost of FMS to affected individuals was approximately $2,275.00. When this was multiplied by the 2 percent documented prevalence of FMS in the general population (8,9), the medical cost of this disorder to the U.S. economy has been estimated to be $12-15 billion annually and the Canadian cost appears to be comparable on a per capita basis. These costs can be divided approximately equally into three categories: (14); hospitalization costs, outpatient care costs, and medication administration costs. Hospitalization for the management of FMS pain finds little justification (16-19). A common reason for hospital admission is to exclude alternate diagnoses, but this can be accomplished more efficiently as an outpatient. It is also important that the physician does not assume that a variety of symptoms are due to FMS when other important inter-current medical conditions may just as likely intervene in these patients as in any other. With better education of physicians and increased awareness of FMS, consideration of this diagnosis early in the patient's course and effective outpatient care may lessen hospitalization care and its associated costs.

D. Taxonomy of FMS

The FMS is properly classified as one of a large group of soft-tissue pain syndromes. Some authors and many clinicians have improperly referred to this category of disorders generically as "myofascial pain disorders" but that confuses the issue with regard to a distinct disorder called "myofascial pain syndrome." Another taxonomic heading of past years was "non-articular rheumatism" but that term is too dated to be currently acceptable. The large group of soft tissue pain syndromes are characterized by pain which emanates from periarticular structures located outside of the joint capsule and periosteum. They differ from arthritic disorders in that the synovial joints are not directly involved. The anatomic structures which appear to be symptomatic can include ligaments, tendons, fascia, bursae, and muscles. All of these soft tissue structures are known to facilitate mechanical functions of the diarthrodial joints. Any of these structures can become painful and dysfunctional alone or in association with distinct inflammatory, autoimmune, arthritic, or endocrine disorders.

The resultant physical dysfunction and compromise in quality of life can be as severe as that associated with any of the arthritic diseases, so these soft tissue pain syndromes are not benign.

The following Table 1 shows a contemporary taxonomy of soft tissue pain syndromes.
Entrapment syndrome
[e.g., carpal tunnel syndrome]
myofascial pain syndrome [MPS]Fibromyalgia syndrome [FMS]
[e.g., biceps tendinitis]
Masticatory myofascial pain syndrome [TMD]Chronic fatigue syndrome [CFS]
Bursitis [e.g., trochanteric bursitis]Chronic regional pain syndrome [CRPS, RSD]Polymyalgia rheumatica [PMR]
Enthesopathies [e.g., tennis elbow]Referred visceral pain [e.g., left shoulder pain
due to angina]
Hypermobility syndrome [HMS]
Adapted from: Russell IJ: J Musculoke Pain 1(1):1-7, 1993.


The main subheadings divide the syndromes into localized, regionalized, and generalized categories. Most of the "localized" conditions are believed to result from repetitive mechanical injury to inadequately conditioned tissues. They are often named anatomically and are disclosed by a typical history plus the exquisite tenderness elicited by digital palpation of the affected structures.

The syndromes with a regional distribution tend to result from "overuse" or other injury. Even though they may involve more than one type of body structure, they are still limited in anatomic scope to a region or body quadrant. The myofascial pain syndrome [MPS] is characterized by "trigger points" [TrPs, contrasted with the different phenomenon and term "tender points," TePs, of FMS] and has traditionally been managed by physiatrists or neurologists. The masticatory myofascial pain syndrome [MMPS] involves the temporomandibular joint and/or TrPs in the muscles of mastication which are typically treated by dentists. Several types of visceral pain can be referred to a musculoskeletal structure [e.g., angina felt in the shoulder or jaw], and the recently renamed chronic regional pain syndrome [CRPS, formerly, reflex sympathetic dystrophy] would be classified in this category.

The "generalized" category implies a systemic process which affects the musculoskeletal system in a more global manner. The chronic fatigue syndrome [CFS] has been characterized by persistent idiopathic fatigue and a number of other constitutional symptoms. It initially presented in epidemics but more recent applications of that diagnosis have emphasized sporadic cases and the current criteria no longer exclude FMS. An overlap between FMS and CFS has led to speculation that they are identical but there are important historical and clinical differences which suggest that they are separate family members of an overlapping soft tissue pain spectrum. People with FMS report chronic widespread pain and are characterized by tenderness to palpation at many of the same anatomic sites involved in some of the localized pain syndromes.

Address correspondence to: Anil K. Jain, BSc, MD, 118, 1025 Grenon Avenue, Ottawa, ON, K2B 8S5, Canada.
[Haworth co-indexing entry note]: "Fibromyalgia Syndrome: Canadian Clinical Working Case Definition, Diagnostic and Treatment Protocols­A Consensus Document." Jain, Anil Kumar et al.
Co-published simultaneously in Journal of Musculoskeletal Pain [The Haworth Medical Press, an imprint of The Haworth Press, Inc.] Vol. 11, No. 4, 2003, pp. 3-107; and: The Fibromyalgia Syndrome: A Clinical Case Definition for Practitioners [ed: I. Jon Russell] The Haworth Medical Press, an imprint of The Haworth Press, Inc., 2003, pp. 3-107. Single or multiple copies of this article are available for a fee from The Haworth Document Delivery Service [1-800-HAWORTH, 9:00 a.m. - 5:00 p.m. [EST]. E-mail address:].
2003 by The Haworth Press, Inc. All rights reserved.

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MAY 12   2009

Awareness Day

Fibromyalgia is a chronic condition, meaning it lasts a long time — possibly a lifetime. However, it may comfort you to know that fibromyalgia is not a progressive disease. It is never fatal, and it won't cause damage to your joints, muscles, or internal organs.


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Fibromyalgia is common and an enormous clinical burden for both patients and society. It is a very complex disease with a variety of symptoms in addition to the defining symptom - chronic widespread pain. These include fatigue, non-restorative sleep, morning stiffness, irritable bowel and bladder, restless legs, depression, anxiety and cognitive dysfunction often referred to as "fibro fog". All of these symptoms cause serious limitations in patients' ability to perform ordinary daily chores and work and severely affect their quality of life. The burden on healthcare and society is high. Research in the UK has shown that diagnosis and positive management of fibromyalgia reduces healthcare cost by avoiding unnecessary investigations and consultations. Yet a recent global survey showed that healthcare professionals lack confidence in diagnosing and managing fibromyalgia. The average time from development of symptoms to diagnosis is over 2 years with unnecessary medical referrals and investigations. Educating the public, patients and healthcare professional to promote better recognising and management of fibromyalgia will benefit patient, healthcare providers and society.
Dr. Ernest Choy
Consultant Rheumatologist and Reader in Rheumatology
Director of Clinical Trials Unit in the Academic Department of Rheumatology
King's College London


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ME/CFS International Awareness Day

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