• Physiology
  1. Genu Varum is a normal finding in the newborn
    1. Nearly all newborns start with Genu Varum
    2. Neutral position by age 2 years
    3. Genu Valgum by age 3-6 years
    4. Returns to neutral or slightly valgus position (esp girls), by age 7-11 years old
  2. Physiologic bowing of the lower extremities
    1. External rotation of femur
    2. Internal rotation of tibia
  • Risk Factors
  1. Osteogenesis Imperfecta
  2. Rickets
  3. Renal Osteodystrophy
  4. Skeletal Dysplasia
  5. Klinefelter Syndrome
  • Symptoms
  1. Noted first at walking age
  • Signs
  1. Knees bow apart
  2. Typically symmetric and bilateral
  3. Measuring degree of Genu Varum
    1. Child stands with medial malleoli touching
    2. Measure distance between medial femoral condyles
    3. Normal intercondylar distance (abnormal if >2 SD outside normal values)
      1. Birth: 0 to 5 cm
      2. Age 13 to 18 months: 0 to 2 cm
      3. Age >=8 years: 0 to 3 cm
  • Differential Diagnosis
  1. Rickets
  2. Skeletal dysplasia
  3. Blount's disease
    1. Obesity-related abnormal growth of medial proximal tibial Physis
  4. Tibial Bowing
    1. Anterolateral bowing
      1. Neurofibromatosis association
    2. Posteromedial bowing
      1. In utero calcaneovalgus foot (will correct)
  5. High impact sports
    1. May generate Genu Varum in teens
  • Management
  1. No management (bracing, connective bars, Orthotics) needed in most cases
  2. Surgical osteotomy may be considered in severe, non-resolving cases
  • Course
  1. Persistence after age 2 years is atypical
    1. Pediatric orthopedic referral is indicated in these cases
  2. Often transitions to Genu Valgum (Knock-Knees)
    1. Occurs between ages 18 months to 3 years
    2. Corrects spontaneously by ages 6 to 10 years
  • Complications
  1. Premature Osteoarthritis