Pintos-Morell , G. and Beck , M. ( 2009 ). Fabry disease in children and the eff ects of en zyme replacement treatment . Eur J Pediatr , 168 , 1355 \200\2231363. Portenoy , R. ( 2006 ). Development and testing of a neuropathic pain screening questionnaire: ID Pain . Curr Med Res Opin , 22 , 1555 \200\2231565. Wallace , M. S. , Lee , J. , Sorkin , L. , Dunn , J. S. , Yaksh , T. , and Yu , A. ( 1997 ) . Intravenous lidocaine: eff ects on controlling pain aft er anti-GD2 antibody therapy in c hildren with neuroblastoma \200\224a report of a series . Anesth Analg , 85 , 794 \200\223 796. Ramaswami , Fabry disease during childhood: clinical manifestations and treatment with agalsidase alfa . Acta Paediatr Suppl , 97 , 38 \200\22340. U. ( 2008 ). Waxman , S. G. , and Dib-Hajj , S. ( 2005 ). Erythermalgia: molecular basis for Ramaswami , U. , Parini , R. , Pintos-Morell , G. , Kalkum , G. , Kampmann , C. , and Beck , M. ( 2011 ). 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Microvascular decompression for pediatric onset trigeminal neuralgia . Neurosurgery , 43 , 804 \200\223807; discussio n 807 \200\223808. Wilkins , K. L. , McGrath , P. J. , Finley , G. A. , and Katz , J. ( 2004 ). Prospective di ary study of nonpainful and painful phantom sensations in a preselected sample of child and adolescent amputees reporting phantom limbs . Clin J Pain , 20 , 293 \200\223301. Ries , M. , Gupta , S. , Moore , D. F. , Sachdev , V. , Quirk , J. M. , Murray , G. J. , et al . ( 2005 ). Pediatric Fabry disease . Pediatrics , 115 , e344 \200\223355. Xiao , W. H. , Yu , A. L. , and Sorkin , L. S. ( 1997 ). Electrophysiological characteristi cs of primary aff erent fi bers aft er systemic administration of anti-GD2 ganglioside anti body . Pain , 69 , 145 \200\223151. Serletis , D. , Parkin , P. , Bouff et , E. , Shroff , M. , Drake , J. M. , and Rutka , J. T. ( 2007 ). Massive plexiform neurofi bromas in childhood: natural history and management issues . J Neurosurg , 106 , 363 \200\223367. Yu , A. L. , Gilman , A. L. , Ozkaynak , M. F. , London , W. B. , Kreissman , S. G. , Chen , H. X. , et al . ( 2010 ). Anti-GD2 antibody with GM-CSF, interleukin-2, and isotretinoin for neuroblastoma . N Engl J Med , 363 , 1324 \200\2231334. Sethna , N. F. , Meier , P. M. , Zurakowski , D. , and Berde , C. B. ( 2007 ). Cutaneous se nsory abnormalities in children and adolescents with complex regional pain syndromes . Pain , 131 , 153 \200\223161. Yue , W. L. ( 2004 ). Peripheral glycerol injection for the relief of facial neuralgia Smith , B. H. , and Torrance , N. ( 2012 ). Epidemiology of neuropathic pain and its impact on quality of life . Curr Pain Headache Rep , 16 (3), 191 \200\2238. in children . Int J Pediatr Otorhinolaryngol , 68 , 37 \200\22341. CHAPTER 22 In \202 ammatory arthritis and arthropathy Peter Chira and Laura E. Schanberg Summary Musculoskeletal pain is a common symptom in infl ammatory arthritides such as juven ile idiopathic arthritis; however, identifying the underlying pathological process is oft e n challenging for health care providers due to the extensive diff erential diagnoses. In ch ildren with infl ammatory arthritides, physical examination abnormalities including swellin g and/or pain on movement and joint limitation accompany the pain at initial presentation. Control of disease activity through anti-infl ammatories and other disease- modifying agent s can limit disease progression and joint damage; however, pain may persist in spite of the se measures. Optimal treat- ment of pain in juvenile idiopathic arthritis and related condi tions is based on a biopsychosocial model, which addresses biological, environmental, and c ognitive-behavioral factors. Analgesics such as opioids and neuropathic pain medications, i n conjunction with other modalities such as pain coping skills training, aerobic exer- cise , and improved sleep hygiene may be appropriate in certain circumstances. Further research is needed to prospectively iden- tify patients and families early in the course of disease who would benefi t from additional support to optimize pain management and limit distress. In addition, future clinical trials should assess the impact of study interventions on pain as a primary endpoint, assessed independently from other response variables. pain processing. However, aggressive medical therapy alone is not suffi cient to optimally treat pain in children with rheumatic condi- tions. Other important concomitant factors bes ides disease activity impact pain perception and management. A biopsychosocial model of pai n more completely addresses all factors contributing to the pain symptoms of a child with a n underlying rheumatic disease, serving as an eff ective framework for treatment ( Figure 2 2.1 ). Mechanisms of arthritis pain Much of what is understood about the biology of joint pain com es from the study of neural pathways in mice models of experimental infl ammatory arthritis (McDougall, 2006 ; McDougall and Larson, 2006 ). Schaible \200\231s extensive work on the basis of pain resulting from infl ammatory arthritides such as rheumatoid arthritis (RA) an d JIA (Schaible et al., 2002 , 2005 , 2009 ) have described two primary mechanisms: periphe ral sensitization (increased sensitivity of noci- ceptive primary aff erent neurons) and ce ntral sensitization (hyper- excitability of nociceptive neurons in the central nervous syst em). Degenerative processes within joints, along with infl ammation, can trigger and exacer bate sensitization of pain pathways, resulting in the development and perpetuation of chron ic pain. Current mech- anistic theories behind the development of pain associated with infl ammation and arthritis in children with rheumatic disease have been reviewed (Kimura and W alco, 2007 ). Primary aff erent neurons have three main functions in nocic- eption: detection of noxious or damaging stimuli (transduction), conveyance of sensory input from the periphery to the s pinal cord (conduction), and synaptic transfer of input to neurons within spe- cifi c lamin ae of the dorsal horn of the spinal cord (transmission) (Kidd and Urban, 2001 ). C-fi bre n ociceptors are activated by ther- mal, mechanical, and chemical stimuli, and can also be se nsitized by mediators of the infl ammatory response (e.g. prostaglandin E2 and bradykinin; see Walker and Baccei, Chapter 6, this volume). Once sensitization occurs, low-level previo usly non-noxious stimu- lation elicits neural activity (Giordano, 2006 ), and pain can be p re- cipitated by routine movement in the presence of infl ammation or joint damage from tra uma or tissue injury. In infl ammatory arthri- tis, a complex interplay of mechanical facto rs and chemical media- tors such as release of bradykinins, prostaglandins, neuropeptides, cytokines, and ion channels is triggered, resulting in a decrease in Introduction Th e evaluation of children with musculoskeletal pain is oft en chal- lenging for health care providers due to the extensive diff erential diagnoses. Identifying any und erlying pathological process in a thoughtful, expeditious manner is extremely important in order to minimize distress of patients and families and prevent long-term dis- ability. Man y practitioners lack comfort and familiarity in determin- ing if musculoskeletal symptoms a nd pain complaints are related to an infl ammatory process such as juvenile idiopathic arth ritis (JIA) or other infl ammatory disorders. Prompt recognition and diagnosis of an underl ying rheumatic disorder allow for early treatment to reduce pain and other symptoms. Ideall y, through treatment, long-term damage to joint or muscle is prevented, limiting physical d isability and/or emotional distress. Additionally, control of infl ammation may decrease pa in signaling and prevent long-term alteration of SECTION 4 pain in specific populations and diseases 216 Disease modifying agents Physical therapy Biological Factors: Disease activity, genetics, pain processing, medications, physical activity, sleep Analgesics Biologics Child s Pain Experience Breathing exercises ercises Environmental Factors: Family therapy cognitive-behavioral Factors: Parental pain and stress response, family relationships, social and school relationships Peer support group Stress, mood, psychological adjustment, selfe \203cacy, coping skills Guided imagery Psychotherapy Parenting training Individualized educational plan Learning not to \200\234catastrophize \200\235 Figure 22.1 Biopsychosocial model of pain. Arthritis pain has multiple factors (biological, environmental, and cognitive-behavioral) that can contribute to a child \200\231s percepti on of pain. Treatment strategies should address the various components that can include pha rmacological and non-pharmacological therapies. perpetuation of pain signals (Milligan and Watkins, 2009 ; see also Vega-Avelaira and Beggs , Chapter 7, this volume). In infl ammatory arthritides such as JIA, the role of glial cell s in perpetuating pain is unclear but growing evidence suggests that cytokines released as part of the infl ammatory cascade can aff ect and alter glial mediated central pain process ing, resulting in dysfunctional pain signaling (Milligan and Watkins, 2009 ). the normal pain threshold within a joint and causing hyperalge- sia and allodynia in local tissues. Infl ammatory cytokines such as tumor necrosis factor alpha (TNF- ), interleuki n 1, and inter- leukin 6 can directly activate nociceptors and contribute to eff ects of in fl ammation itself (via swelling aff ecting mechanical nocicep- tion), which helps to initi ate and perpetuate the pain signal (Kidd and Urban, 2001 ; Oen et al., 2005 ). Th us, newer biological agents to control infl ammatory arthritis using anticytokine therapies may impa ct arthritis pain directly, as well by decreasing disease activity. Joint infl ammation als o produces central sensitization occurs when various neurotransmitters (e.g. L-glutamate) a nd neuropeptides (e.g. substance P, neurokinin A) activate and/or modulate synapses within the dorsal horn in the spinal cord, leading to enhancement of the pain signal and potential expansion of pain receptive fi elds via postsynaptic receptor activation (Schaible et al., 2009 ). Pain can be modulated by: reducing central sensitization via antagonism of post- s ynaptic receptors (e.g. N-methyl-D-aspartate (NMDA); Schaible et al., 2006 ); local inhibit ory and excitatory interneuron circuits within the dorsal horn; as well as descending pathw ays (e.g. from the rostral medulla) that can facilitate or inhibit spinal nociceptive proce ssing (Schaible et al., 2005 ). Imaging studies in adults have also shown that cortical pro cesses have a major role in the mediation of pain processing that includes elements of cogn ition, arousal state, attention, and expectation (Seifert and Maihofner, 2009 ; see also Fi tzgerald, Chapter 8; Hermann, Chapter 40, this volume). Chronic pain in children with rheumatic disease is the result of an integration of biologic al processes (e.g. glial cell activation, periph- eral and central sensitization), psycholo gical factors (e.g. anxiety, poor coping), and sociocultural contexts (e.g. parental emotio nal distress, peer relationships) within a developmental framework (Zeltzer et al., 1997 ). Disease activity and day to day life experi- ences, including emotional state, sleep quali ty, and family and peer relationships, all impact the severity, characteristics, and regula rity of pain with time. Ongoing pain can result in sensitization of the peripheral and cent ral nervous systems, producing neurophysi- ological, neurochemical, and neuroanatomical cha nges (Woolf and Salter, 2000 ), which may continue despite low disease activity or the abse nce of tissue damage. In addition, the extent of disability associated with a specifi c chr onic pain level varies from person to person based on genetics as well as many of the biops ychosocial factors that impact pain perception. In summary, pain perception is multifactori al and best understood using a biopsychosocial frame- work including developmental status, coping ability, mood, stress levels, as well as environmental and family factors, in additi on to disease status and severity (Rapoff and Lindsley, 2000 ). Increasingly recognized as an important factor in the estab- lishment of chronic pain is th e role of accessory glial cells in the CHAPTER 22 inflammatory arthritis and arthropathy 217 Clinical presentation Children and adolescents presenting with rheumatic disease may not ha ve musculoskeletal pain as their sole, primary presenting complaint. However, for children with chronic infl ammatory arthri- tis, joint pain can be a major presenting symptom. Inter estingly, McGee looked at all patients presenting to a pediatric rheuma- tology clinic, and of 111 patients with an initial chief complaint of isolated musculoskeletal pain, only one had arthritis or other rheumatic disease (McGhee et al., 2002 ). Th ese fi ndings confi rm ed earlier data, which showed that the majority of patients referred to pediatric rheumatol ogy clinics across the US do not have pri- mary rheumatic disease but rather non-specifi c musculoskeletal complaints or abnormal laboratory studies (such as a positive anti- nuclear antibody; Bowyer and Roettcher, 1996 ). Both studies high- light the need for health care professionals to distinguish those with non-specifi c musculoskeletal pain from those with infl ammatory conditions. variance, and day-to-day variations of pain are infl uenced by factors such as mood, stress , parental and child coping, and parental pain and health beliefs (Schanberg et al., 2003 , 2005 ). Although a relationship between increased disease activity and increased pain exists (Malle son et al., 2004 ; Vandvik and Eckblad, 1990 ; Varni et al., 1987 ), research consistently has demonstrated limited predictive value for disease status variables. Across stud- ies, d isease status variables typically predict only a small to medium proportion of the variance in children \200\231s pain ratings (8 \200\22328%; Malleson et al., 2004 ; Schanberg et al ., 1997 ; Th ompson et al., 1987 ; Vandvik and Eckblad, 1990 ). Th erefore, it is impor- ta nt to delineate other infl uential factors in the pain experience of children with JIA. Th e most highly predictive models of pain variance conceptual- ize pain report as infl uen ced by multiple factors, including disease variables, demographic variables, psychological variables (such as coping and mood), and environmental factors. In a sample of 56 children with chronic arthritis, Ross and colleagues reported that increased child anxiety, increase d maternal distress, and increased family harmony were associated with higher child pain ra tings averaged over a 1-month time period (Ross et al., 1993 ). Th e authors hypothesized t hat increased family harmony might lend itself to increased responsiveness to children \200 \231s pain behav- iour, serving to reinforce pain behavior and pain reporting in children. When joint pain is the primary complaint for a patient present- ing with infl ammatory arth ritis such as JIA, it is accompanied by overt abnormalities on examination such as swelling and/or pain on movement with limitation of motion, or tenderness noted at the joint line a long with limitation. Th e pain of arthritis is typi- cally described as mild to moderate, dull or achy discomfort, with joint stiff ness that worsens with inactivity (sleeping or si tting for prolonged periods) and improves with movement. Pain at rest is unusual. Pain comm only varies from day to day; however, the physical examination abnormalities are constantly present. Oft en, the stiff ness is described as a \200\230gel phenomenon \200\231 in whic h inactiv- ity causes a sensation within the aff ected joint(s) similar to gelatin setting or glue drying, although the exact pathophysiology of why this occurs is not understood. Ar thritis pain rarely causes night awakening; therefore, other causes of joint or bone pain m ust be ruled out including malignancy, infection, or bone tumors (oste- oid osteoma) if nig ht pain is the primary complaint. Other signs of chronic infl ammatory arthritis include ga it abnormality such as limp, warmth of the joint (not necessarily associated with erythema) , and muscle atrophy of proximally or distally aff ected areas. If there is erythema and/or exquisite tenderness with palpation of joints or bones, infection (such as osteomyelitis o r septic arthritis), reactive processes (such as rheumatic fever or Henoch \200\223Sch n lein purpura), malignancy (such as leukemia, lymphoma, or neuroblastoma), or trauma should be considered before making the diagnosis of JIA or other rheumatic disease. Table 22.1 lis ts the diff erential diagnoses to consider when children present with musculoskeletal pain. Demographic variables such as age may infl uence JIA-related pain, but fi ndings in cross-s ectional studies have not been repro- ducible. Hagglund and Malleson both identifi ed older age as a pre- dictor of pain in their respective cohorts (Hagglund et al., 1995 ; Malleson et al., 2004 ), but other investigators have not found this relationship (Ross et al., 199 3 ; Vandvik and Eckblad, 1990 ). Th e role of psychosocial variables such as emotional distress, mood, stress, and pain-copi ng strategies in children \200\231s pain report- ing has been studied in many settings. Sch anberg and co-workers investigated interrelationships of daily stress, daily mood, and dis- ease expression. Results of multilevel random eff ects models indi- cated that day-to-day fl uctuations in mood and stressful events were related to daily symptoms in children with polyarticular forms of juvenile chronic arthritis (Schanberg et al., 2000 , 2005 ). Specifi cally, worse mood and more stressful events predicted increased daily pain, fatigue, and s tiff ness. Th ese results confi rm other studies which indicate that increased psychologica l distress (e.g. stress, depression, and anxiety) is related to increased pain reporting an d poorer functional outcomes, such as decreased participation in school and social activiti es (Hoff et al., 2006 ; Margetic et al., 2005 ; Ross et al., 1993 ). Hoff and colleagues fo und that depressive symptoms reported by children with JIA at a baseline evaluation were pr edictive of reports of pain and functional disability 6 and 12 months later (Hoff et al., 2 006 ). Pain variables in arthritis Th e intensity of pain reported by children and adolescents wit h JIA is quite variable. Early studies of pain in children with JIA erroneously suggested t he condition was less painful than RA (Laaksonen and Laine, 1961 ). More recent studies in the 1990s, incorporating more developmentally appropriate measures, showed disease-related pain is oft en underestimated in children with JIA and other rheumatic disorders. In fact, using daily diary methodology, Schanberg and colleagues reported that children with JIA rep ort pain on 70% of days (Schanberg et al., 2003 ). Most children reported mild to mod- erat e pain, but 25% of children reported pain in the severe range. Interestingly, disease activ ity predicts less than half of reported pain Children \200\231s coping with pain is another infl uential factor. Th e use of catastrophi zing (i.e. engaging in overly negative thinking about pain) and decreased pain-coping effi cacy predict higher pain inten- sity across several pain measures and more painful body loc ations, even aft er controlling for demographic variables and medical status variables (Sch anberg et al., 1997 ). In a laboratory setting, catastro- phizing also predicted higher pai n intensity, decreased pain toler- ance, and increased pain-related discomfort in children with JIA undergoing experimental cold pressor pain (Th astum et al., 1997 , 2001 ). Recent studies by Th astum and colleagues underscore the SECTION 4 pain in specific populations and diseases 218 Table 22.1 Di \200 erential diagnoses for musculoskeletal pains in children Category Diagnosis Hallmarks Anatomic or mechanical issues Avascular necrosis Pain with weight bearing Osteochondroses (e.g. Legg \200\223Calf \200\223Perthes) Hip pain and limp Apophysitis (e.g. Osgood \200\223Schlatter) Tibial tuberosity pain Ligamentous laxity (e.g. patellar dislocation) Mobile patella with pain Benign hypermobility syndrome Multi-joint hyperextensibility Trauma Fracture Multiple fractures in young children suggest child abuse; growth plate fractures not seen o n X-ray Sprain, muscular strain Physically active teens, unusual <4 years of age Haemarthrosis (e.g. hemophilia) Warm, pain with motion, grossly bloody arthrocentesis Infections Reactive arthritis Post-diarrhoeal or genitourinary infections Rheumatic fever Exquisitely tender migratory polyarthritis of large joints Lyme disease Oligo- or polyarthritis is a manifestation of late Lyme infection Viral arthritis (e.g. Epstein \200\223Barr virus, cytomegalovirus, parvo B19) Often with rash and fever Infectious osteomyelitis (bacterial, fungal, tuberculosis) May be associated with sympathetic e \200 usion of adjacent joint Septic arthritis Typically is associated with redness, warmth, pain with motion, elevated in \202 ammatory markers Malignancy or other tumors Leukemia Severe night pain can be associated with bony point tenderness and complete blood count abn ormalities Lymphoma Matted lymph nodes Osteoid osteoma Night-time pain, often alleviated by NSAIDs Neuroblastoma Abdominal mass Rheumatic diseases Juvenile idiopathic arthritis Multiple subgroups based on clinical characteristics Systemic lupus erythematosus Non-erosive polyarthritis Henoch \200\223Sch nlein purpura Purpuric rash on legs, buttocks; arthritis of lower extremities Dermatomyositis Bilateral proximal muscle weakness and rash on face, eyelids, and extensor surfaces of join ts Sarcoidosis Joints boggy and painless, associated with rash and in \202 ammatory eye disease Other in \202 ammatory conditions Arthropathy related to in \202 ammatory bowel disease Peripheral arthritis re \202 ects gastrointestinal (GI) disease activity versus axial skel etal arthritis which is independent of GI disease Auto-in \202 ammatory disorders Periodic fever syndromes, C1AS mutations Chronic recurrent multifocal osteomyelitis (non-infectious) Multi-focal a \200 ecting long bones as well as mandible, spine, and clavicles; bone biops y needed for diagnosis Arthritis from immunode \201 ciency Combined variable immunode \201 ciency Pain ampli \201 cation disorders Complex regional pain syndrome Type 1 associated with trauma and with di \200 use swelling and discoloration of a \200 e cted limb Fibromyalgia Sleep disturbance, fatigue and tender points Benign limb pains of childhood (e.g. growing pains) Night awakenings with extremity pain relieved by massage or warm packs Metabolic and endocrinological Rickets Flaring at bony metaphyses on X-ray Mucopolysaccharidoses Gaucher or Hurler CHAPTER 22 inflammatory arthritis and arthropathy 219 Diagnostic studies Although infl ammatory arthritis is typically a clinical diagno- sis, la boratory and/or radiographic evaluations can be helpful in classifying the subtype of JIA o r determining if arthritis is part of a systemic disorder. A complete blood count with manu al diff er- ential, erythrocyte sedimentation rate (ESR) and/or C-reactive protein are oft en performed to assess for generalized infl am- mation. A comprehensive metabolic panel, in cluding uric acid and lactate dehydrogenase to look for possible increased cellu- lar turno ver noted in malignancies, and urinalysis are useful to assess organ damage or involvement. If pain is not localized at a joint but more diff use, muscle enzymes such as creatine kin ase or aldolase as well as vitamin D and thyroid function levels may be helpful. Oft en, th ese ancillary studies are useful in identifying other aetiologies of joint or bony pain suc h as metabolic diseases and malignancies. impact of cognitive health beliefs on pain in children with JIA (Th astum and Herlin, 2011 ; Th astum et al., 2005 ). Results suggested beliefs about control over pain and the abilit y to function despite the presence of pain infl uence the development of eff ective pain- c oping strategies, while dysfunctional health beliefs persist over time in patients with hig h pain. Finally, parent and family environmental variables are related to pain report of children w ith JIA. Th ese variables include the nature of family relationships (family harmony or con fl ict), increased par- ent psychological distress, parental responses to child pain, and p arent and family pain history (Connelly et al., 2010 ; Iobst et al., 2007 ; Reid et al., 20 05 ). For example, in a sample of school-aged children with chronic arthritis, Schanberg an d colleagues found that a more extensive parent and family history of pain was related to i ncreased child self-reported pain intensity (Schanberg et al., 2001 ). Moreover, within the context of hierarchical regression analyzes, child catastrophizing mediated the relationsh ip. In other words, parent and family pain variables infl uenced a child \200\231s use of c atastrophizing as a coping strategy, which in turn infl uenced child reporting of pain. Th e utility of screening autoantibodies varies depending on the context of ordering the te st. If joint or musculoskeletal pain is the only complaint without obvious joint pathology such as swelling or pain on movement/tenderness with limitation (arthralgias), then screeni ng tests have little value and cause undue consternation if abnormal (Wong et al., 2012 ). In the presence of true arthritis, screening for anti-nuclear antibody, rheumatoid factor ( especially for polyarticular presentation), anti-citrullinated cyclic peptide, and HLA-B27 is helpful to determine prognosis and risk of eye dis- ease (Anonymous, 1993 ; Heiligenhaus et al., 2007 ). Diagnosis Th e diagnosis of chronic infl ammatory arthritis is based on clinical examinatio n and history. No laboratory or radiographic studies make the diagnosis of JIA. Duration of symptoms is extremely important as diagnostic criteria for all the chronic arthritides req uire the pres- ence of objective joint abnormalities on physical examination (either swelli ng or pain/tenderness with limitation) in the same joint for at least 6 weeks \200\231 time . Acute presentations of joint pain and/or swelling caused by infections, injury, or reacti ve processes are more common than JIA, and oft en are self-limited, resolving before 6 week s. Th e pediatric Gait, Arms, Legs screen (pGALs) is an excellent screen- ing tool for use by non-rheumatologists that includes a focused joint examination for aff ected areas which incorporates inspection, pal- pation, and range of motion (Foster et al., 2006 ). Radiographic studies assess bony abnormalities or joint destruc- tion such as erosions, but oft en in JIA these diagnostic studies are negative, especially early in the disease cours e. MRI and ultrasound are newer modalities used in assisting the diagnosis of arthritis by demonstrating eff usions, synovial proliferation, early erosions, increased blood fl ow, an d bone marrow oedema from infl amma- tion, but there are issues with regard to normal stand ards in the growing skeleton. Th erefore, imaging studies are best evaluated by an experien ced pediatric musculoskeletal radiologist in conjunc- tion with a pediatric rheumatologist. Classi \201 cation Th e nomenclature for childhood onset arthritis has evolved through the years. Th e current classifi cation system was devel- oped by the International League Aga inst Rheumatism (ILAR; Fink, 1995 ; Petty et al., 1998 , 2004 ) and uses the term juvenile idiopathic arthritis (JIA) instead of juvenile rheumatoid arthri- tis (American College of Rheumatology classifi cation; Brewer et al., 1972 , 1977 ) or juvenile chronic arthritis (E uropean League Against Rheumatism classifi cation; Wood, 1978 ). While the dif- ferent clas sifi cation systems have similarities, they are not inter- changeable. Within the ILAR clas sifi cation of JIA, there are seven categories corresponding to diff erent onset subtypes b ased on the fi rst 6 months of presentation, which include: oligoarticular, pol- yarticular -rheumatoid factor negative, polyarticular-rheumatoid factor positive, psoriatic, enthesiti s-related, systemic, and unclas- sifi ed arthritis. Th e ILAR criteria were developed to he lp provide prognostic information for various subtypes of JIA, as well as pro- vide a frame work for research; however, the classifi cation scheme is cumbersome and oft en misused eve n by pediatric rheumatolo- gists. In addition, large numbers of patients fall into the uncl as- sifi ed category (Berntson et al., 2001 ; Kunjir et al., 2010 ; Merino et al., 2001 ; P etty, 2001 ; Ravelli et al., 2011 ). Other rheumatic conditions Systemic lupus erythematosus, juvenile dermatomyositis, and vas- culitis can all present with arthritis as a primary manifestation. Joint or muscle pain ca n be the presenting symptom for these patients. Typically, other signs and symptoms includi ng rash and constitutional symptoms such as malaise, fever, fatigue, or ano- rexia guide fu rther evaluation. Screening for organ system dam- age by looking at renal, cardiopulmonary, and neuropsychiatric function can be helpful in making diagnoses of other rheumatic condit ions. Treatment/management of pain in children with JIA Th e biopsychosocial model of pain provid es a useful framework from which to approach managing pain in JIA. In addition to aggressiv ely treating the biological basis of disease, a combina- tion of pharmacological and non-ph armacological modalities can be used to manage pain. Reducing disease activity is associate d with improved radiographic outcomes, functional capability and reduced symptoms including pain; however, disease control is not