What is the recommended evaluation and treatment for a 2-year-old child presenting with a limp in the right leg, without pain or history of trauma?

Painless Limp in a 2-Year-Old: Urgent Evaluation Required

A 2-year-old with painless limp requires immediate evaluation with thorough physical examination focusing on hip pathology, followed by imaging to rule out developmental dysplasia of the hip (DDH), septic arthritis, or other serious conditions that can present without pain at this age.

Critical Red Flags in This Presentation

• Asymmetric gait in a toddler is a red flag requiring urgent evaluation 1
• Painless limp does NOT rule out serious pathology—young children may not localize or communicate pain effectively
• At 2 years old, this child is beyond the typical age for DDH screening but still within the window where late-presenting DDH can occur 2

Immediate Evaluation Steps

Physical Examination Priorities

• Hip examination is paramount: Check for limited range of motion, particularly abduction and internal rotation 2
• Assess leg length discrepancy (Galeazzi sign) which may indicate hip pathology 2
• Examine for asymmetric thigh or gluteal folds 2
• Evaluate gait pattern carefully—antalgic versus Trendelenburg gait
• Check for fever, warmth, or effusion suggesting septic arthritis 3
• Neurologic examination to rule out foot drop or other nerve involvement 1

Imaging Strategy

• Plain radiographs of the pelvis/hips are the initial imaging study of choice at this age 4
• At 2 years, radiographs are more appropriate than ultrasound (ultrasound is primarily for infants <6 months) 2
• Look for acetabular index abnormalities, Shenton line disruption, or femoral head position 2
• If radiographs are normal but clinical suspicion remains high, consider ultrasound to evaluate for hip effusion or MRI for occult pathology 4

Differential Diagnosis to Consider

Most Serious (Cannot Miss)

• Septic arthritis of the hip—can present with minimal pain in young children, requires urgent surgical drainage 3
• Late-presenting DDH—painless limp with hip instability or subluxation 2
• Occult fracture or stress injury—may not be visible on initial radiographs 4

Other Important Considerations

• Transient synovitis (most common cause of limp in this age group, but typically has some pain)
• Early Legg-Calvé-Perthes disease (though more common 4-8 years)
• Toddler's fracture of tibia (though usually follows minor trauma) 4
• Neurologic causes including tethered cord or peripheral nerve injury 2, 1

Referral Indications

• Immediate pediatric orthopedic referral if: 5, 1

  • Abnormal hip examination findings
  • Radiographic abnormalities detected
  • Concern for septic arthritis (fever, elevated inflammatory markers, refusal to bear weight) 3
  • Asymmetric leg findings or deformity 5, 1

• Pediatric neurology referral if: 1

  • Abnormal neurological examination
  • Foot drop or weakness identified
  • Regression of motor skills 1

Common Pitfalls to Avoid

• Do not assume painless means benign—serious hip pathology can present without significant pain in toddlers
• Do not attribute to normal developmental variants (in-toeing, tibial torsion) without proper evaluation—these typically do not cause limp 6, 7
• Do not delay imaging—waiting for "spontaneous resolution" risks missing time-sensitive diagnoses like septic arthritis or DDH 2, 3
• Approximately 10% of fractures may only appear on follow-up radiographs 7-14 days later 4—if initial films are negative but limp persists, repeat imaging is essential

Management Before Specialist Evaluation

• Limit weight-bearing activities until diagnosis is established
• Avoid empiric bracing or orthotics without diagnosis 5, 7
• Document baseline range of motion and gait pattern for comparison
• If septic arthritis is suspected, obtain inflammatory markers (ESR, CRP, CBC) and blood cultures before antibiotics 3