Juvenile Rheumatoid Arthritis

- Discussion:
    - JRA is a persistent non infectious arthritis lasting more than 6 wks to 3 months after other possible etiologies have bee ruled out;
    - most common chronic childhood rheumatoid dz;
    - affects girls more than boys;
    - synovial proliferation leads to joint destruction (chondrolysis) & soft tissue destruction;
    - severe joint destruction is seen in only 5% of patients;
    - differential diagnosis:
          - leukemia
          - septic arthritis
          - sarcoidosis
    - in order to confirm the diagnosis, one of the following is required:
          - rash, presence of RF, iridocyclitis, C-spine dz, pericarditis, tenosynovitis, intermittent fever, or AM stiffness;
    - sub-types:
          - pauciarticular: 4 or less joints in > 6 mo.
          - polyarticular: 5 or more joints in > 6 mo.
          - systemic JRA: begins w/ high spiking fevers ( > 39.3) & rash;

- Labs:
     - synovial fluid exam:
     - antinuclear antibody test:
            - positive antinuclear antibody test is diagnostic of JRA;
            - most often positive in younger females with oligoarticular disease and has increased risk for anterior uveitis

- Radiographic Changes: radiographs can show rarefeaction of juxta articular bone;

- General Clinical Findings:
    - cervical spine in JRA:
         - atlantoaxial instability makes intubation potentially hazardous (consider lateral flexion and extension radiographs);
         - children w/ seronegative JRA tend to have stiff necks 2nd to spontaneous fusion of the posterior fascets;
         - reference: Changes in the cervical spine in juvenile rheumatoid arthritis.
    - upper extremity: JRA
    - lower extremity:
         - flexion contractures (hip and knee flexed, & ankle dorsiflexed), subluxations & other deformities (hip protrusio, valgus knees, & equinovarus feet);
         - growth deformities of the limbs:
                - JRA may either cause lower extremity overgrowth (in patients less than age 9) or may lead to physeal arrest (in patients older than age 9);
                - generally, when the disease develops before age 9, will have overgrowth of involved extremity, but overgrowth will not exceeded 3.0 cm;
                       - major discrepancy developed within the first 3-4 yrs and will then either increase very slowly thereafter, will remain level, or will decrease;
                - reference:
                       - Leg-length discrepancies in monoarticular and pauciarticular juvenile rheumatoid arthritis.
         - hip:
                - references:
                       - Total hip arthroplasty in juvenile rheumatoid arthritis. Two to eleven-year results.
                       - Total hip and knee arthroplasty in juvenile rheumatoid arthritis.
                       - Involvement of the hip in juvenile rheumatoid arthritis. A longitudinal study.
         - knee:
                - this joint is affected most often in JRA (66%) followed by ankle in 25%;
                - reference:
                       - Total hip and knee arthroplasty in juvenile rheumatoid arthritis.
         - foot:
                - in polyarticular JRA, simultaneous involvement of ankle & subtalar joints & remainder of the joints in the foot is common;
                - ankle contracts into equinus (talipes equinus);
                - subtalar joint may develop a varus or valgus deformity;

- Treatment:
    - includes night splinting, salicylates, and rarely, synovectomy (for chronic swelling refractory to medical management);
    - arthrodesis and arthroplasty may be required for severe JRA:
          - note: mortality rate for JRA pts undergoing arthroplasty is approx 18%, w/ death occurring before the third decade


Late results of synovectomy in juvenile rheumatoid arthritis.

Disorders of the sacro-iliac joint in children.

Methotrexate in resistant juvenile rheumatoid arthritis. Results of the U.S.A.-U.S.S.R. double-blind, placebo-controlled trial. The Pediatric Rheumatology Collaborative Study Group and The Cooperative Children's Study Group.

Radiographic changes in juvenile chronic polyarthritis

The radiology of juvenile rheumatoid arthritis. A review of the English language literature.

Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Tuesday, August 21, 2012 4:21 pm