What is the appropriate evaluation and management for a 1 year and 7 month old patient (pt) presenting with acute onset bilateral leg pain and a transient episode of refusal to walk, with previously normal X-rays (radiographs)?

Evaluation and Management of a 1-Year-7-Month-Old with Bilateral Leg Pain and Refusal to Walk

For a 1-year-7-month-old child presenting with bilateral leg pain and transient refusal to walk, the initial evaluation should include targeted radiographs of the tibia/fibula, as these are the most common sites of occult fractures in this age group, even when previous radiographs were reported as normal.

Key History Elements to Obtain

• Timing and pattern of pain episodes:

  • When did the pain start? How long did each episode last? 1
  • Is the pain intermittent or constant? 1
  • Does the pain occur at night or wake the child from sleep? (concerning for more serious pathology) 1

• Trauma history:

  • Any known or witnessed falls or injuries? 1
  • Any changes in activity level or new physical activities? 1

• Associated symptoms:

  • Presence of fever or recent illness (suggests infectious etiology) 1
  • Refusal to bear weight (duration and consistency) 1
  • Changes in appetite, energy level, or behavior 2

• Developmental milestones:

  • When did the child start walking? 1
  • Any recent regression in motor skills? 1

Physical Examination Focus

• Observation of gait (if child is willing to walk):

  • Look for limping pattern, antalgic gait, or refusal to bear weight 1
  • Assess symmetry of movement 1

• Lower extremity examination:

  • Inspect for swelling, redness, or deformity 1
  • Palpate for areas of tenderness along bones and joints 1
  • Assess range of motion of hips, knees, and ankles 1
  • Look for asymmetric hair growth, skin changes, or muscle atrophy 1

• Neurological assessment:

  • Muscle strength testing (as tolerated in this age group) 1
  • Deep tendon reflexes 1
  • Response to light touch and pain 1

Diagnostic Approach

• Initial imaging:

  • Focused radiographs of tibia/fibula (most common site of occult fractures in this age group) 1
  • Consider radiographs of other areas if examination suggests localized pathology 1

• Laboratory studies (if infectious or inflammatory process suspected):

  • Complete blood count (CBC) 1
  • Erythrocyte sedimentation rate (ESR) 1
  • C-reactive protein (CRP) 1

• Advanced imaging (if initial evaluation is negative and symptoms persist):

  • MRI of the lower extremities (sensitive for soft tissue, cartilage, and bone pathology) 1
  • Ultrasound of hips (if hip pathology suspected) 1

Differential Diagnosis

• Trauma-related:

  • Occult or toddler's fracture (spiral tibial fracture) - most common cause 1
  • Stress fracture 1, 3
  • Soft tissue injury 1

• Infectious/inflammatory:

  • Transient synovitis (most common cause of acute hip pain in children) 4
  • Septic arthritis 1
  • Osteomyelitis 1

• Developmental:

  • Developmental dysplasia of the hip 1
  • Growing pains (typically in older children) 5

• Neurological:

  • Cerebral palsy 1
  • Spinal cord abnormalities 1

Management Recommendations

• For normal radiographs with improving symptoms:

  • Observation and reassurance 1
  • Consider mild analgesics (acetaminophen) for pain control 4
  • Follow-up in 1-2 weeks if symptoms persist 1

• For normal radiographs with persistent symptoms:

  • Repeat clinical examination 1
  • Consider follow-up radiographs (some fractures only become visible on follow-up imaging) 1
  • Consider advanced imaging (MRI or ultrasound) 1

• For abnormal findings:

  • Orthopedic consultation for fractures or joint abnormalities 1
  • Infectious disease consultation for suspected infection 1

Important Pitfalls to Avoid

• Assuming normal radiographs rule out fracture - approximately 10% of tibial fractures are only visible on follow-up radiographs 1

• Focusing only on the site of reported pain - young children may not accurately localize pain, and hip pathology can present as knee or thigh pain 1

• Missing signs of infection - always assess for fever and inflammatory markers when evaluating unexplained limping 1

• Inadequate follow-up - ensure appropriate follow-up for persistent symptoms, as serious conditions like spinal discitis have been missed on initial evaluation 1