494 Annals of the Rheumatic Diseases 1993; 52: 494-496

EXTENDED REPORTS Ann Rheum Dis: first published as 10.1136/ard.52.7.494 on 1 July 1993. Downloaded from

Joint hypermobility and fibromyalgia in schoolchildren

Abraham Gedalia, Joseph Press, Moti Klein, Dan Buskila

Abstract activities that hyperextend the joint capsule Objectives-To test the hypothesis that and other soft tissue constituents may cause joint hypermobility may play a part in injury.4 Fibromyalgia is a syndrome of diffuse the pathogenesis of in fibromyalgia, muscle and joint pain most common in schoolchildren were examined for the adults.5 6 Although it has been reported to coexistence of joint hypermobility and cause diffuse musculoskeletal pain and fatigue fibromyalgia. in children, its prevalence is not well Methods-The study group consisted of documented.7 The purpose of this study was to 338 children (179 boys, 159 girls; mean age examine schoolchildren for the coexistence of 11*5 years, range 9-15 years) from one the two clinical disorders (joint hypermobility public school in Beer-Sheva, Israel. In the and fibromyalgia to test the hypothesis that assessment of joint hypermobility, the joint hypermobility may play a part in the criteria devised by Carter and Bird were pathogenesis of pain in fibromyalgia. used. Any child who met at least three of five criteria was considered to have joint hypermobility. Children were considered Subjects and methods to have fibromyalgia if they fulfilled the The study group consisted of 338 school- 1990 American College of Rheumatology children aged 9-15 years in one of the public criteria for the diagnosis of fibromyalgia, schools in Beer-Sheva, Israel. There were 179

namely, widespread pain in combination (53%) boys and 159 (47%) girls (mean age http://ard.bmj.com/ with tenderness of 11 or more of the 18 11.5 years, range 9-15 years). specific tender point sites. The blind After informed consent had been obtained, assessments of joint hypermobility (by two experienced rheumatologists indepen- AG) and fibromyalgia (by DB) were dently blindly assessed joint hypermobility carried out independently. (AG) and fibromyalgia (DB). This was per- Results-Of the 338 children 43 (13%) formed simultaneously in two separate rooms.

were found to have joint hypermobility All children were evaluated before noon. on September 25, 2021 by guest. Protected copyright. and 21 (6%) fibromyalgia; 17 (81%) of the In the assessment of joint hypermobility, the 21 with fibromyalgia had joint hyper- following criteria devised by Carter and mobility and 17 (40%) of the 43 with joint Wilkinson,8 with modifications by Bird et al,9 hypermobility had fibromyalgia. Using x2 were used: (a) hyperextension of the fingers statistical analysis, joint hypermobility so that they lie parallel to the forearms; and fibromyalgia were found to be highly (b) apposition of the thumbs to the surface of associated. the forearms; (c) hyperextension of the elbows Department of Conclusions-This Pediatrics, Louisiana study suggests that >10°; (d) hyperextension of the knees >10°; State University there is a strong association between and (e) flexion of the trunk with the knees Medical Center, New joint hypermobility and fibromyalgia in straight and touching the palms of the hands Orleans, LA, USA schoolchildren. It is possible that joint to the floor. A Gedalia hypermobility may play a part in the A child who met at least three of the Pediatric and Adult Rheumatology Units, pathogenesis of pain in fibromyalgia. five criteria was considered to have joint Soroka Medical More studies are needed to establish the hypermobility. Center, clinical significance ofthis observation. In the assessment of fibromyalgia, children Ben Gurion University and parents were about ofthe Negev, questioned widespread Beer-Sheva, Israel (Ann Rheum Dis 1993; 52: 494-496) musculoskeletal pain and aching. A point J Press count of 18 tender points was conducted in all M Klein children. The children were considered to have D Buskila It is well established that joint hypermobility fibromyalgia if they fulfilled the currently Correspondence to: Dr A Gedalia, may predispose children to the development of accepted American College of Rheumatology Department of Pediatrics, joint pain.' 2 This disorder is an extreme (ACR) criteria for the classification and Louisiana State University Medical Center, variation of normal joint mobility with no diagnosis of fibromyalgia, namely widespread 1542 Tulane Avenue, underlying connective tissue disease.3 The pain in combination with tenderness of 11 or New Orleans, LA 70112-2822, USA. mechanism by which joint symptoms develop more of the 18 specific point sites.'0 Digital Accepted for publication in this disorder is not well understood, though palpation was conducted with an approximate 9 February 1993 excessive motion or inappropriate physical force of 4 kg. For a tender point to be 'positive' J7oint hypermobility and fibromyalgia in schoolchildren 495

Table 1 Prevalence ofJoint hypernobility (7H) and Discussion fibromyalgia (FM) in 338 schoolchildren It has previously been clearly shown that No (%.) withJH No (%/6) with FM significant numbers of children with joint Ann Rheum Dis: first published as 10.1136/ard.52.7.494 on 1 July 1993. Downloaded from Boys (n=179) 20 (11) 7 (4) hypermobility have articular symptoms.2 The Girls (n=159) 23 (14) 14 (9) pathogenesis in which pain develops in joint Total (n=338) 43 (13) 21 (6) hypermobility is not well understood, though The difference in the prevalence ofJH and FM between the two it may be speculated that it might be related sexes is not statistically significant. to microtrauma due to misuse or overuse, or both. Another sometimes the subject must state that the palpation is diagnosed in children is fibromyalgia.7 This is painful. Finally, the data were analysed using a chronic syndrome of musculoskeletal pain, x2 statistical analysis. the aetiology of which is unknown. The patho- genesis of fibromyalgia is not clear; however, sleep disturbances in stage 4 non-rapid eye Results movement sleep, muscle hypoxia, generalised Joint hypermobility was detected in 43 (13%) muscle deconditioning, and mechanical stress of the 338 children. The prevalence of joint have been suggested to play a part.5 The model hypermobility (table 1) was 14% in girls of pathophysiology described by Yunus'2 may (23 children) and 1 1% in boys (20 children) explain the mechanism of fibromyalgia among with no statistical differences between them children with joint hypermobility, as peripheral (X2=0*8; P=05). trauma factors in joint hypermobility may Fibromyalgia was diagnosed in 21 (6%) of initially cause localised joint pain, which would the 338 children (table 1). The frequency of then cause neuroendocrine dysfunction fibromyalgia among boys of 4% (seven boys) through central nervous system plasticity, was not significantly different (x2=3 0; p=O 1) leading to widespread pain and tenderness. from that of 9% in girls (14 girls). The present study shows a significant Seventeen (81%) of the 21 children with association between joint hypermobility fibromyalgia had joint hypermobility. Seven- and fibromyalgia. This may explain in part teen (40%) of the 43 children with joint hyper- the mechanism by which pain develops in mobility had fibromyalgia v 4 (1%) of 295 fibromyalgia. The association of these two children without joint hypermobility (table 2). disorders is not well understood. Cognitive- The association between joint hypermobility behavioural intervention in children with and fibromyalgia was statistically significant fibromyalgia has been shown to be effective in (x2=93; p

reported pain nor had any of the other features psychological factors may also play a part in http://ard.bmj.com/ such as fatigue or irritable bowel syndrome, this disorder. It should be stressed that in any and therefore did not fulfil the ACR criteria for child who presents with diffuse musculo- the diagnosis of fibromyalgia. Three of these skeletal pain, joint hypermobility and fibro- seven children had joint hypermobility, should both be considered in the however. Of the 21 children with fibromyalgia, differential diagnosis. 13 had a history of recurrent episodes of leg Although the two disorders will benefit from

pain, four had episodes of leg pain and low drugs and exercises for symptomatic pain, the on September 25, 2021 by guest. Protected copyright. , two had recurrent , and paediatrician needs to assure the anxious and two had recurrent episodes of abdominal pain fearful parents that these are benign and not and headaches. Of these children, only one had crippling phenomena. Most interesting are the a history of morning stiffness. Evaluation seven healthy children with more than 11 carried out by their family doctor showed no tender points but no widespread pain. Whether underlying organic diseases, though a diagnosis these subjects are more likely to develop pain ofgrowing was made in 10 ofthem. Sleep syndromes in the next few years remains to be disturbances and psychological factors were seen. not assessed and no data on these parameters In summary, the prevalence of fibromyalgia are available. More details on the assessment in schoolchildren was 6% and 40% among of the non-articular tenderness in these children with joint hypermobility. The associ- children using a Chatillon dolorimeter have ation between joint hypermobility and fibro- been described elsewhere."l Briefly, it was myalgia was highly significant. More studies shown that in general the boys had a lower are needed to establish the clinical significance degree of tenderness than the girls. The of this observation. children with fibromyalgia had lower thresholds for tenderness at control and tender 1 Gedalia A, Person D A, Brewer E J, et al. Joint hypermobility in juvenile episodic arthritis/. J Pediatr 1985; points than the subjects without fibromyalgia. 107: 873-6. 2 Gedalia A, Press J. Articular symptoms in hypermobile schoolchildren. A prospective study. Pediatr 1991; 119: Table 2 Relation betweenjoint hypermobility (7H) and 944-6. fibromyalgia (FM) in 338 schoolchildren 3 Kirk J A, Ansell B M. Bywaters E G L. The hypermobility syndrome: musculoskeletal complaints associated with No withJH No withoutJYH Total generalized joint hypermobility. Ann Rheum Dis 1967; 26: 419-25. No with FM 17* 4 21 4 Lewkonia R M. Hypermobility of joints. Arch Dis Child No without FM 26 291 317 1987; 62: 1-2. Total 43 295 338 5 Smythe H A. Nonarticular rheumatism and psychogenic musculoskeletal syndrome. In: McCarty D J, ed. Arthritis The association between JH and FM is highly statistically and allied conditions. Philadelphia: Lea and Febiger, 1989: significant (x'=93; p<0 0001). 1241-54. 496 Gedalia, Press, KMein, Buskila

6 Goldenberg D L. Diagnostic and therapeutic challenges of College of Rheumatology 1990 criteria for the classi- fibromyalgia. Hosp IPract 1989; 24: 39-52. fication of fibromyalgia: report of the multicenter criteria

7 Yunus M B, Masi A T. Juvenile primary fibromyalgia committee. Arthitis Rheum 1990; 33: 160-72. Ann Rheum Dis: first published as 10.1136/ard.52.7.494 on 1 July 1993. Downloaded from syndrome. A clinical study of thirty three patients and 11 Buskila D, Press J, Gedalia A, et al. Assessment of non- matched normal controls. Arthnitis Rheum 1985; 28: articular pain tenderness and prevalence of fibromyalgia 138-45. in children. JRheumatol 1993; 20: 368-70. 8 Carter C, Wilkinson J. Persistent joint laxity and congenital 12 Yunus M B. Towards a model of pathophysiology of dislocation of the hip. Bone Joint Surg [Br] 1964; 46: fibromyalgia: aberrant central pain mechanisms with 40-5. peripheral modulation. Rheumatol 1992; 19: 846-50. 9 Bird H A, Brodie D A, Wright V. Quantification of joint 13 Walco G A, Ilowite N T. Cognitive-behavioral intervention laxity. RheumatolRehabil 1979; 18: 161-4. for juvenile primary fibromyalgia syndrome. Rheumatol 10 Wolfe F, Smythe H A, Yunus M B, et al. The American 1992; 19: 1617-9. http://ard.bmj.com/ on September 25, 2021 by guest. Protected copyright.