Transient (toxic) synovitis

Background

  • Self-limiting inflammatory process of the hip
  • Most common cause of acute hip pain in children <10yr
    • Peak incidence 3-8yrs, with a mean of 6 yrs
  • Male:Female is 2:1
  • Usually unilateral
  • 32-50% present after recent viral URI
  • Possible posttraumatic or allergic pathologies

Clinical Features

  • Abrupt onset of unilateral hip pain, limp, and restricted hip motion
  • Nontoxic appearance
  • May have a low grade fever

Differential Diagnosis

Pediatric hip pain

Evaluation

Work-up

  • X-ray if suspicious for fracture
  • Plain films or ultrasound can show effusion
    • If effusion found consider arthrocentesis
    • Presence of effusion does not rule in or out transient synovitis as bilateral effusions can occur in 25% of children

Evaluation

Must distinguish from septic arthritis

  • Transient Synovitis favored by:
    • Temperature <38.5
    • ESR <20
    • WBC <12,000
    • CRP <2
  • Septic arthritis favored by:
    • Temperature >38.5
    • ESR >40
    • WBC >12,000
    • CRP >2
    • severe pain with ROM

Kocher Criteria for septic arthritis of the hip

  • ESR > 40 mm/hr
  • WBC > 12,000/microliter
  • Refusal or inability to weight bear on affected joint
  • Fever 38.5° C or greater
Number of Kocher Criteria Chance of Septic Joint
1 3%
2 40%
3 93%
4 99%

Management

  • Return to full activity as tolerated
  • NSAIDs

Disposition

  • If diagnosis is certain, follow up with primary care provider within 1 week as needed

See Also

References