Objectives. The development of
We describe three cases of infantile tibia vara
resulting from an atraumatic slip of the proximal tibial epiphysis
upon the metaphysis. There appears to be an association between
this condition and severe obesity. Radiologically, the condition
is characterised by a dome-shaped metaphysis, an open growth plate
and disruption of the continuity between the lateral borders of
the epiphysis and metaphysis, with inferomedial translation of the
proximal tibial epiphysis. All patients were treated by realignment
of the proximal tibia by distraction osteogenesis with an external
circulator fixator, and it is suggested that this is the optimal
method for correction of this complex deformity. There are differences
in the radiological features and management between conventional
infantile Blount’s disease and this ‘slipped upper tibial epiphysis’
variant.
A total of 25 children (37 legs and 51 segments) with coronal plane deformities around the knee were treated with the extraperiosteal application of a flexible two-hole plate and screws. The mean age was 11.6 years (5.5 to 14.9), the median angle of deformity treated was 8.3° and mean time for correction was 16.1 months (7 to 37.3). There was a mean rate of correction of 0.7° per month in the femur (0.3° to 1.5°), 0.5° per month in the tibia (0.1° to 0.9°) and 1.2° per month (0.1° to 2.2°) if femur and tibia were treated concurrently. Correction was faster if the child was under 10 years of age (p = 0.05). The patients were reviewed between six and 32 months after plate removal. One child had a rebound deformity but no permanent physeal tethers were encountered. The guided growth technique, as performed using a flexible titanium plate, is simple and safe for treating periarticular deformities of the leg.
