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