Dr / Hytham Dr / Hytham NafadyNafady

Congenital tibia vara Congenital tibia vara Osteochondrosis tibiae deformansOsteochondrosis tibiae deformans

DefinitionDefinition

Progressive tibial bowing related to Progressive tibial bowing related to growth suppression of the growth suppression of the posteromedial proximal tibial physis.posteromedial proximal tibial physis.

EtiologyEtiology

Compressive stress on the Compressive stress on the posteromedial proximal tibial physis.posteromedial proximal tibial physis.

Predisposing factors:Predisposing factors: Early walking.Early walking. Overweight.Overweight. African American (more lax African American (more lax

ligaments).ligaments).

DistributionDistribution

Bilateral > unilateral.Bilateral > unilateral.

TypesTypes

Infantile form.Infantile form. Adolescent form.Adolescent form.

Metaphyseal diaphyseal Metaphyseal diaphyseal angle:angle:

It is an angle between a line drawn It is an angle between a line drawn through the widest portion of the through the widest portion of the proximal tibial metaphysis and proximal tibial metaphysis and another line drawn perpendicular to another line drawn perpendicular to the long axis of the tibial shaft.the long axis of the tibial shaft.

Normally 0 Normally 0 –– 11 11 > 11 = Blount disease.> 11 = Blount disease.

DDx of Blount disease DDx of Blount disease

Developmental (physiological) bowing:Developmental (physiological) bowing:

Developmental bowing Developmental bowing Blount diseaseBlount disease

Disappear after 2 years.Disappear after 2 years. Progressive.Progressive.

Bilateral and symmetric.Bilateral and symmetric. Unilateral or bilateral asymmetric.Unilateral or bilateral asymmetric.

Metaphyseal diaphyseal angle < 11Metaphyseal diaphyseal angle < 11 Metaphyseal diaphyseal angle > 11Metaphyseal diaphyseal angle > 11

Surgical treatment of Blount Surgical treatment of Blount diseasedisease

High tibial osteotomy (either curved High tibial osteotomy (either curved or wedged osteotomies).or wedged osteotomies).