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uvenile Rheumatoidrthritis and Total Hip Arthroplasty

ajiv Gandhi, MD, SM, FRCSC,a and Nizar Mahomed, MD, ScD, FRCSCb

Juvenile rheumatoid arthritis (JRA) is the most common rheumatic disease of childhood.Hip joint involvement is the most significant factor impacting mobility and independence ofthe child. The persistent synovitis can lead to physeal growth injury and cartilage destruc-tion. The first line of treatment involves anti-inflammatory medications, physiotherapy, andintra-articular injections. Surgical treatment options include soft tissue release of contrac-tures, synovectomy, and joint arthroplasty. The results of joint replacement in this popu-lation are encouraging however there are many anatomical challenges in this population.The optimal method of fixation remains yet unclear.Semin Arthro 19:261-266 © 2008 Elsevier Inc. All rights reserved.

KEYWORDS juvenile arthritis, hip disease, hip arthroplasty, synovitis

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uvenile rheumatoid arthritis (JRA) or juvenile idiopathicarthritis has been recently redefined by the American

heumatology Association as arthritis lasting � 6 weeks inuration with an onset before age 16 years. In Europe, theame disease is known as juvenile chronic arthritis in whichhe definition has been extended to a duration of symptomsf �3 months.Juvenile rheumatoid arthritis is the most common rheu-atic disease in childhood and affects twice as many females

s males. The incidence of the disease is about 11.7 cases per00,000 population per year. There are three subtypes of theisease, which are based on the clinical and laboratory find-

ngs that are present during the first 6 months. Systemic onsetRA is characterized by fevers and rash in addition to therthralgia. Pauciarticular disease refers to involvement of fourr fewer joints and occurs in up to 50% of children with JRA.olyarticular disease involves five joints or more and occurs

n 40% of kids with JRA. Juvenile rheumatoid arthritis can beither seropositive or seronegative.

Juvenile rheumatoid arthritis generally has a better prognosishan the adult form. Many children will achieve a permanentemission of their disease as they enter adulthood and of thosehat do have persistent synovitis, not all will develop bony ero-ion or cartilage damage. Risk factors for a more aggressive formf the disease include an early age of onset and those with rheu-

Toronto Western Hospital, Toronto, Ontario, Canada.University of Toronto, Toronto, Ontario, Canada.ddress reprint requests to Rajiv Gandhi, MD, FRCSC, Toronto Western

Hospital, 399 Bathurst Street, East Wing 1-439, Toronto, Ontario M5T

a2S8, Canada. E-mail: rajiv.gandhi@uhn.on.ca

045-4527/08/$-see front matter © 2008 Elsevier Inc. All rights reserved.oi:10.1053/j.sart.2008.10.003

atoid factor (RF)-positive polyarticular disease. Joint destruc-ion and arthritis will likely develop in 50% of those patientsith persistent RF-positive disease compared with 10% of thoseith RF-negative disease.1

Psychosocial development of a child with JRA may be af-ected through poor self-esteem, poor body image, and lim-ted independence.2 These children often have multiplechool absences and their ability to participate in physicalducation reflects the severity of their disease.

Infection has been suggested as a cause of both the onset andxacerbations of JRA.3 Multiple viral and bacterial antigens haveeen theorized to promote an inappropriate host autoimmuneesponse leading to the clinical manifestations of the disease.he etiology of the disease is however likely multifactorial asewer research indicates an inherited genetic predisposition.here is an increased familial incidence of JRA in those childrenith HLA-B27 and HLA-DR haplotypes.4 Further study into theenetics and disease pathways will aid in early detection andpecifically targeted therapies (Table 1).

Hip joint involvement in JRA is the most significant factorffecting mobility and independence of the child.5,6 Theathophysiology of the disease involves an aggressive prolif-ration of joint synvoium and effusion, which cause pain andecondary muscle spasm. With persistant synovial hypertro-hy, articular cartilage destruction, and physeal growth in-

ury of both the femur and acetabulum may occur. Theseestructive changes lead to a constellation of symptoms, in-luding pain, loss of motion, and joint contractures. Coxaagna may be seen through overgrowth of the femoral neck

nd a varus deformity (Fig. 1). Avascular necrosis (AVN) may

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262 R. Gandhi and N. Mahomed

ccur usually secondary to the prolonged use of corticosteroids.ip subluxation or dislocations may be seen with more severe

ases. Spontaneous hip fusion may occur but is quite rare.Further support for the importance of hip joint involve-ent in JRA comes from a study by Modesto and coworkers7

hat reviewed the charts of 91 children with systemic onsetRA for a minimum of 3 years. They collected clinical andiological variables at baseline and at 6 months to identifyredictive factors for those that will develop severe multijointestruction. Through the use of multivariate logistic regres-ion modeling, the presence of hip involvement and polyar-hritis were independent predictors of a poorer articular out-ome.7 Lang and coworkers8 reported on those children withystemic onset JRA and showed a high incidence of earlynset hip joint degeneration. Twenty of 42 (48%) kids hadadiographic evidence of hip arthritis, including 7 with hip

able 1 Juvenile Arthritis Classification

Systemic Ty

ex predominance M�F Fypical age of onset Any <heumatoid Factor Negative Negntinuclear antibodies Negative 60veitis — 30atients with JRA (%) 10 4

Figure 1 Anteroposterior pelvis and lateral x-ray left hipcase of JRA. The left hip shows acetabular dysplasia,

degenerative joint disease.

ubluxation. One patient developed hip subluxation within 2ears and the remaining 6 patients developed subluxationithin 6 years of disease onset.The optimal study for imaging the hip joint has tradition-

lly been the plain radiograph, but magnetic resonance im-ging (MRI) and ultrasound (US) may offer some clinicaldvantages. The use of US to detect hip disease in early stagess attractive because of the lower costs compared with MRInd potentially comparable sensitivity. In a study of 53 pa-ients published by Federezzi and coworkers,9 they showedhat US detected hip joint abnormalities in 47% of patientsompared with 19% with conventional radiographs. More-ver, severe radiographic changes in the hips were found 2 toyears later in three of nine patients who initially had normal-rays but abnormal ultrasounds. The answer to the questionf what is the best test for imaging the hip joint in JRA is yet

ciarticular Polyarticular

Type II RF neg RF pos

M F F>8 <5 >8

Negative Negative PositiveNegative 25%� 60%�

— <10%� —15 25 10

g previous uncemented right total hip arthroplasty in ace of coxa magna with a narrow femoral canal, and

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JRA and THA 263

ndecided, but one author suggested that plain films and MRay be best for initial staging, MR is the best test for assessing

nflammatory changes in the joint, while US is good for as-essing effusions, pannus, and treatment response.10

reatmentonservative Management

n the early stages of hip involvement, the medical treatmentf the disease is critical. Traditionally, nonsteroidal anti-in-ammatory drugs (NSAIDS) or selective COX-II inhibitorsre effective at controlling the level of joint synovitis andnflammation.11 Unfortunately about 30% of patients willontinue to have symptomps that are refractory to NSAIDSnd will require disease-modifying antirheumatic drugsDMARDS).11

Chemotherapeutics such as corticosteroids and metho-rexate are effective for controlling disease symptoms butong term use should be balanced against potential side ef-ects. Corticosteroid use over many years can lead to growthetardation and Cushings syndrome while long-term metho-rexate use can lead to bone marrow suppression and hepa-otoxicity. The use of tumor necrosis factor-alpha antagonistss currently being investigated. At present, weekly metho-rexate in considered the first-line treatment followingSAIDS, but in time the biologic agents such as etanercept,

nfliximab, and anakinra may be shown to be more effective.Secondary to the chronic joint synovitis, patients often

evelop joint capsule and periarticular muscle contractures,articularly of the adductor and iliopsoas muscles. Physio-herapy and stretching exercises should be instituted early inhe treatment of these patients to delay the onset of fixed jointontractures. Periodic intra-articular injections of steroidsave been shown to have a predictable and substantial ben-fit on joint pain and mobility.12,13

urgical Managementerioperative Considerationsmultidisciplinary approach to the perioperative care of

hese patients should include the expertise of a social worker,hysiotherapist, rheumatologist, anesthesiologist, and ortho-edic surgeon. Cervical spine instability may preclude these of a general anesthestic and affect patient positioninguring surgery. Mandibular hypoplasia can lead to difficul-ies around the jaw while temporomandibular joint inflam-ation can impair visualization of the trachea during intuba-

ion.14

Patients often have involvement of multiple joints, such asnees, feet, shoulders, and elbows, which may impair theostoperative rehabilitation process. A thorough preopera-ive evaluation by the occupational and physical therapistsay help to facilitate a patient’s recovery through havinguch needed resources available such as splints, braces, and

ssistive walking aids. A full evaluation by the rheumatologistor associated systemic involvement of the pericardium, re-

piratory system, and blood clotting factors should be under- w

aken. A stress dose of steroids may need to be given preop-ratively as well as discontinuation of some antirheumaticrugs.

urgical Considerationswide surgical exposure during joint replacement surgery is

ritical considering the significant joint contractures and al-ered anatomy that is normally present in these patients. Aide capsulotomy combined with a soft tissue release ante-

ior and posterior is recommended to limit the risk of fractureuring dislocation. In a series of 75 patients, Ruddlesdin andoworkers15 noted a significant number of cases required ann situ femoral neck osteotomy for bony ankylosis or protru-ion deformities. A percutaneous adductor tenotomy at theime of surgery can improve abduction and decrease the riskf posterior instability. Patients with bilateral arthritis andignificant hip flexion contractures may benefit from simul-aneous bilateral hip replacements (or closely staged apart) torevent recurrence of contractures.Most surgical reports traditionally used a trochanteric os-

eotomy for exposure;14,16 however, it much less commonlysed now. Potential advantages of the osteotomy include ac-ess to the femoral canal and the potential to correct versiont the time of reattachment. The femoral canal is usuallyypoplastic and osteopenic in these patients, increasing theisk of fracture during preparation. Secondary to the chronicontractures and premature closure of the physes, there isften proximal femoral torsion and increased anteversion.here is often a diaphyseal/metaphyseal mismatch present

hat would benefit from the use of a modular femoral com-onent if uncemented fixation is chosen. Colville andaunio17 had three femoral fractures in their series of 41ncemented femoral stems with standard components. Scottnd coworkers18 recommended the use of customized com-onents or congenital dysplasia of the hip-type stems in thisopulation.The challenges on the acetabulum generally fall into two

orms. The acetabulum may have a shallow, dysplastic shapeith a lateral and superiorly subluxated hip that appears

imilar to developmental hip dysplasia. Autogenous bonerafting from the resected femoral head can be used to aug-ent segmental defects. The second more common defor-ity is protrusion with superior medial migration of the hip

enter with loss of medial wall bone. The surgical goal withoth deformities is to obtain stable fixation and to restore thenatomic hip center. In one series, patients with a hip centerlaced �5 mm outside the anatomic location had twice theailure rate as those with an anatomic hip center.16 JRA pa-ients classically have thin bone in the ilium and this willompromise fixation of a high hip center. The surgeonhould ensure availability of small diameter reamers andmall acetabular shells to prepare the socket. Alternate bear-ng surfaces such as metal/metal or ceramic/ceramic couldotentially be very beneficial in this population as polyethyl-ne liners are often thin considering the small acetabularhells. Preoperative computed tomography scans may be

arranted for assessing pelvic bone stock.

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264 R. Gandhi and N. Mahomed

Operating on patients with open growth plates presentsnother technical challenge. Failure rates up to 67% haveeen reported for cemented sockets in those with open phy-es.19 Scott and coworkers18 recommended triradiatepiphysiodesis with bone grafting on the acetabular side andhe use of a longer prosthetic neck on the femoral side toompensate for the loss of height expected from removal ofhe femoral growth plate. Deferring surgery until skeletalaturity would be recommended.

urgical Treatmenturgical management early in the course of the disease in-olves treatment of hip joint contractures. Muscular contrac-ures can contribute to bony structural deformities over time.he evidence for a beneficial clinical effect of early adductornd psoas tenotomies is building. Many authors have shownustained beneficial effects after 4 to 5 years follow up inerms of pain relief and joint mobility.20-22 Poor results fromsolated soft tissue release can be expected if advanced de-enerative changes are present in the joint.23

Open hip synovectomy, once a routine operation per-ormed for early stages of the disease, has since become lessopular. Early literature has shown only modest short-termymptom relief with no change in the natural history of theisease.6,24 In these studies, the benefits were found to notutweigh the potential risks of open hip dislocation. He-mkes and Stotz25 showed a benefit of open synovectomy at 2ears in their case series of only six hips. More recent workas evaluated surgical outcomes with validated scores andtandardized functional evaluations. These authors reportedn 67 hips with a mean 4-year follow up and concluded an5% excellent outcome.26 The use of hip arthroscopy in JRAas first reported in 1981 by Holgerrson and coworkers27

ho reported on its use for diagnostic purposes. This mini-ally invasive technique may allow for a more complete

ynovectomy without the risk of open dislocation.When the joint degeneration becomes severe enough and

he patient’s quality of life is limited, joint replacement sur-ery is an excellent option. With involvement of both theips and knees, Scott28 recommended treatment of the hip

oint arthritis first. Hip fusion is contraindicated in this pop-lation because of the polyarticular nature of the disease andhe potential for involvement of the contralateral hip. Theurgical procedure of choice must consider the complicatingactors in this population of a young age, femoral and acetab-lar dysplasia, and muscular contractures.The results of bipolar hemiarthroplasty have been less than

ncouraging in the past. Yun and coworkers29 reported a8% failure rate at 10 years follow up defined as definite

oosening and/or revision to total hip arthroplasty. The mostommon reason for failure was progressive superomedial ac-tabular migration.29 The patch porous coating design of theemoral stem used in this study likely also contributed to theigh failure rate. Although there exists no matched compar-

son trial in the literature comparing hemiarthroplasty to to-

al hip arthroplasty, the Harris Hip Scores (HSS) of the former e

ption generally fall short of that in the total hip arthroplastyreated patients.

Total hip arthroplasty remains the surgical treatment ofhoice as it has been shown to give reliable improvement inatient pain and function.17,30,31 Lachiewicz and coworkers16

eported a mean postoperative HHS of 78 in their series.aric and Haynes32 and Haber and Goodman33 reported 93

o 100% of patients were pain free at medium term follow up.uddlesdin and coworkers15 showed that, despite achievingxcellent pain relief, 25% of patients still required tworutches to ambulate or remained wheelchair bound. Manyuthors report outcomes based on the HHS score, which is aell recognized and validated scoring system for isolated hipathology, but many of these patients have multiple joint

nvolvement. There remains a need for a validated scoringystem relevant to young JRA patients with multijoint in-olvement whose quality of life is affected by unique mentalealth, social, and physical factors.Moreover, the pelvic osseous anatomy often necessitates

sing an acetabular component with a small outer diameter,hereby resulting in a thinner polyethylene bearing surface.lthough patients with JRA often have low demands of theirips, this is not reflected in long-term survivorship studies.Research on the durability of fixation has shown variable

esults in the literature, with the greatest failure rates re-orted for cemented acetabular fixation (Table 2). Rates ofailure or loosening for cemented cups has been shown to bes high as 25 to 60% in long-term follow up.16,31,34-37 Wrob-ewski and coworkers38 reviewed 195 Charnley low frictionrthroplasties at a mean 15-year follow up and concluded a2% rate of acetabular loosening and a 7 to 8% rate of femoraltem loosening. Lehtimaki and coworkers39 reported someery optimistic 15-year results in 186 patients treated withemented Charnley total hip replacements. The overall fem-ral survivorship at 15 years was 91.9% compared with7.8% for the acetabular component. They concluded thatatient use of systemic steroids was a risk factor for implantailure. It is important to note that many of these studies wereone before the advent of highly cross-linked polyethylene

iners, which may showed improved survivorship results inuture studies.

There exist few reports on cementless fixation of hip ar-hroplasty in this patient population. Kitsoulis and cowork-rs40 reported on 20 hip arthroplasties of which all acetabularups were uncemented and 50% of all femoral stems werencemented. All patients experienced excellent pain reliefnd there were no failures for the femoral stems at a mean0-year follow up. Two acetabular cups (10%) required re-ision due to aseptic loosening.40 Lachiewicz41 reported00% survival in 10 patients at 4.5 years while Maric andaynes32 reported no failures in four uncemented hips at-years follow up.The optimal method of fixation in this population remains

nclear but the issues to be considered are the patient’s func-ional demands, the potential benefits of putting antibioticsn the cement for prophylaxis against infection, and the bonyemodeling that occurs as the patient ages. The bony remod-

ling is affected by factors such as medication use, disuse,

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JRA and THA 265

utritional status, and natural course of the disease itself.40

oreover, many studies do not distinguish the subtype ofRA their patients had and it cannot be concluded if the moreggressive forms of the disease, such as the systemic onset orolyarticular variants, have different long-term outcomeshan the pauciarticular group.

onclusionhe care of the child with JRA involves awareness of both thehysical and psychosocial impacts of the disease. Conserva-ive management with NSAIDS and DMARDs can be effectivet controlling joint synovitis and effusions. Concurrent phys-otherapy is essential to prevent joint contractures that caneverely limit a child’s level of physical function. Surgicalreatment options of joint capsule and muscle contractureelease may be effective at improving patient quality of lifend function; however, it will not alter the natural history ofhe disease.

Total hip arthroplasty is an effective solution to treat end-tage joint degeneration; however, the optimal method ofxation remains yet undecided. Surgical considerations inhese patients include dysplasia and bone stock deficienciesn both the femoral and acetabular sides. Further long-termtudies with strict inclusion criteria and validated outcomeeasures evaluating uncemented fixation are needed.

eferences1. Wallace CA, Levinson JE: Juvenile rheumatoid arthritis: Outcome and

treatment for the 1990s. Rheum Dis Clin North Am 17:891-906, 19912. Beales JG, Holt PH, Keen JH, et al: Children with juvenile chronic

arthritis: Their beliefs about their illness and therapy. Ann Rheum Dis42:481-486, 1983

3. Pugh MT, Southwood TR, Gastron JS: The role of infection in juvenile

able 2 Summary of Studies Reporting Survivorship of Hip ar

N

roblewski et al38 2007Cemented 130

ehtimaki et al39 1997Cemented 186hmell et al34 1997Cemented 66

aber and Goodman33 1998Cemented 10 Fem 2 CupsUncemented 20 Fem 27 Cups

itsoulis et al40 2006Cemented 10 FemUncemented 10 Fem 20 Cups

achiewicz et al41 1986Cemented 34

uddlesdin et al15 1986Cemented 75aric and Haynes al32 1993Cemented 13Uncemented 4

chronic arthritis. Br J Rheumatol 32:838, 1993 1

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asty in JRA

ean Follow Up (years)

Survivorship (%)

Cups Stems

15 78 93.1

15 87.8 91.9

12 65 82

4.5 100 90100 100

9.2 N/A 10090 100

6 74 92

5.4 100 98.7

9.3 82 71100 100

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9. Williams WW, McCullough CJ: Results of cemented total hip replace-

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ment in juvenile chronic arthritis: A radiologic review. J Bone Joint SurgBr 75:872-874, 1993

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2. Witt JD, McCullough CJ: Anterior soft-tissue release of the hip in juve-nile chronic arthritis. J Bone Joint Surg Br 76:267-270, 1994

3. Hyman BS, Gregg JR: Arthroplasty of the hip and knee in juvenilerheumatoid arthritis. Rheum Dis Clin North Am 17:971-983, 1991

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0. Lachiewicz PF: Porous-coated total hip arthroplasty in rheumatoid ar-thritis. J Arthroplasty 9:9, 1994

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5. Witt JD, Swann M, Ansell BM: Total hip replacement for juvenilechronic arthritis. J Bone Joint Surg Br 73:770, 1991

6. Severt R, Wood R, Cracchiolo A 3rd, et al: Long-term follow-up ofcemented total hip arthroplasty in rheumatoid arthritis. Clin OrthopRelat Res 265:137, 1991

7. Learmonth ID, Heywood AW, Kaye J, et al: Radiological loosening aftercemented hip replacement for juvenile chronic arthritis. J Bone JointSurg Br 71:209, 1989

8. Wroblewski M, Siney PD, Fleming PA: Charnley low-frictional torquearthroplasty in young rheumatoid and juvenile rheumatoid arthritis:292 hips followed for an average of 15 years. Acta Orthoped 78:2,206-210, 2007

9. Lehtimaki MY, Lehto MUK, Kautiainen H, et al: Survivorship of thecharnley total hip arthroplasty in juvenile chronic arthritis: A follow upof 186 cases for 22 years. J Bone Joint Surg Br 79:792-795, 1997

0. Kitsoulis PB, Stafilas KS, Siamopoulou A, et al: Total hip arthroplasty inchildren with juvenile chronic arthritis: Long term results. J PediatrOrthop 26:8-12, 2006

1. Lachiewicz PF: Rheumatoid arthritis of the hip. J Am Acad Orthop Surg

5:332-338, 1997