What is the recommended evaluation and management of joint pain in children?

Evaluation and Management of Joint Pain in Children

The recommended approach to evaluating and managing joint pain in children includes a systematic assessment for infectious, inflammatory, traumatic, and neoplastic causes, followed by targeted treatment based on the underlying etiology, with NSAIDs and intra-articular glucocorticoid injections as first-line therapy for juvenile idiopathic arthritis. 1, 2

Initial Evaluation

History - Key Elements

• Duration of symptoms (acute vs. chronic)
• Pattern of joint involvement (monoarticular, oligoarticular, polyarticular)
• Morning stiffness (suggestive of inflammatory arthritis)
• Constitutional symptoms (fever, weight loss, fatigue)
• Recent trauma or infection
• Family history of autoimmune conditions

Physical Examination

• Complete joint examination focusing on:
  • Swelling, warmth, tenderness, erythema
  • Range of motion limitations
  • Joint stability
  • Extra-articular manifestations (rash, lymphadenopathy, hepatosplenomegaly)

Red Flags Requiring Urgent Evaluation

• Fever >38.5°C with joint pain (highly specific for septic arthritis) 3
• Inability to bear weight
• Severe pain or night pain
• Systemic symptoms (weight loss, night sweats)
• Joint effusion with limited motion

Laboratory Testing

First-Line Tests

• Complete blood count (CBC)
• Erythrocyte sedimentation rate (ESR)
• C-reactive protein (CRP)

The combination of CRP >7 mg/L and ESR >12 mm/hr provides the best positive likelihood ratio (6.26) for identifying orthopedic infections 4

Second-Line Tests (Based on Clinical Suspicion)

• Joint fluid analysis if effusion present (cell count, culture, Gram stain)
• Blood cultures if fever present
• Throat culture if pharyngitis present

Tests to Avoid in Primary Care

• "Rheumatological/autoimmune disease screen" has no diagnostic role in juvenile idiopathic arthritis 5
• Antinuclear antibodies (ANA) and rheumatoid factor (RF) should not be ordered routinely as they have low diagnostic utility in primary care settings 5, 6

Imaging

Plain Radiographs

• Indicated for:
  • Suspected fracture
  • Slipped upper femoral epiphysis
  • Bone tumors
  • Baseline assessment in chronic arthritis

Ultrasound

• Superior for detecting:
  • Joint effusions
  • Synovial thickening
  • Soft tissue inflammation

MRI

• Indicated for:
  • Suspected osteomyelitis
  • Early inflammatory changes not visible on radiographs
  • Complex joint pathology

Management Algorithm

1. Infectious Arthritis

• If suspected (fever >38.5°C, elevated CRP, high WBC count) 3:
  • Urgent orthopedic referral for joint aspiration
  • Empiric antibiotics after cultures obtained
  • Hospitalization for IV antibiotics and possible surgical drainage

2. Juvenile Idiopathic Arthritis (JIA)

Initial Therapy for Oligoarticular JIA

• NSAIDs are conditionally recommended as part of initial therapy 1, 2
• Intra-articular glucocorticoid injections (IAGCs) are strongly recommended 1
  • Triamcinolone hexacetonide is the preferred agent 1
• Oral glucocorticoids are conditionally recommended against as part of initial therapy 1

For Inadequate Response to Initial Therapy

• Conventional synthetic DMARDs are strongly recommended 1
  • Methotrexate is conditionally recommended as the preferred agent over leflunomide, sulfasalazine, and hydroxychloroquine 1
• Biologic DMARDs are strongly recommended if inadequate response to NSAIDs, IAGCs, and at least one conventional synthetic DMARD 1

3. Non-Inflammatory Causes

• Mechanical/overuse pain:
  • Rest, activity modification
  • Physical therapy
  • NSAIDs for symptomatic relief

4. Pain Management

• Use validated pain assessment tools appropriate for age 1:
  • Faces Pain Scale-Revised (FPS-R) for children 4-12 years
  • Visual Analog Scale (VAS) for children 6 years and older
  • Numerical Rating Scale (NRS-11) for children over 6 years

Monitoring

For NSAIDs

• CBC, liver function tests, and renal function tests are conditionally recommended every 6-12 months 1

For Methotrexate

• CBC, liver function tests, and renal function are strongly recommended within the first 1-2 months of usage and every 3-4 months thereafter 1
• Folic/folinic acid supplementation is strongly recommended in conjunction with methotrexate 1

Referral Criteria

Emergency Referral

• Suspected septic arthritis
• Inability to bear weight
• Severe pain with systemic symptoms

Urgent Referral (1-2 weeks)

• Persistent joint swelling >4 weeks
• Multiple joint involvement
• Significant functional limitation

Routine Referral

• Chronic joint pain without clear diagnosis
• Suspected inflammatory arthritis
• Poor response to initial management

Adjunctive Therapies

• Physical and occupational therapy are conditionally recommended regardless of concomitant pharmacologic therapy 1
• A healthy, age-appropriate diet is strongly recommended 1
• Specific diets to treat JIA are strongly recommended against 1
• Supplemental or herbal interventions specifically to treat JIA are conditionally recommended against 1

Remember that early diagnosis and treatment are crucial to prevent long-term joint damage and disability in children with inflammatory arthritis.