DefinitionCongenital posteromedial bowing of tibia.
EpidemiologyAssociated with leg length discrepancy, calcaneovalgus foot, and tight anterior structures.
- It is not associated with other anomalies such as neurofibromatosis or with tibial fractures or pseudoarthrosis.
PathoanatomyUsually affects the middle and distal thirds of the tibia.
EtiologyThought to be due to intrauterine positioning.
SignsInspection: Posteromedial bowing and leg length discrepancy. It is often associated with a calcaneovalgus foot. The dorsum of the foot may be in contact with the anterior tibia in this condition.
- Leg length discrepancy: The limb is usually shortened 1-1.5 cm at birth. Some of the children will have limb length discrepancies that average 4.0 cm at maturity. The growth inhibition usually remains as a constant percentage over time.
X-rayWill show posteromedial bowing of tibia.
OverviewThere is usually spontaneous correction in the first years of life, but it rarely resolves completely. The patient should be monitored to evaluate leg length discrepancy.
Nonoperative TreatmentIndication: Most cases.
Method: Observation. No orthotics are necessary. Angular deformity corrects spontaneously, but medial bowing may persist. Calcaneovalgus foot resolves gradually.
Operative TreatmentLeg length discrepancy (LLD):
- Method: The growth inhibition usually remains as a constant percentage over time, thus allowing future equalization procedures can be planned. LLD can be treated with casting, contralateral epiphysiodesis or ipsilateral limb lengthening. Tibial osteotomies are usually not indicated.