Abstract
Blount's disease is by far common cause of significant genu varum in paediatric age group. The deformity can range from simple varus deformity to significant varus, shortening of tibia and internal torsion of tibia, depending up on type and stage of Blount's disease. Several studies have shown excellent correction with the use of circular frame. The trend has moved from Ilizarov circular frame to Taylor Spatial Frame. The most accepted method of achieving correction of all components is by performing proximal tibial osteotomy and gradual correction of mechanical axis. Traditionally two additional procedures – fibular osteotomy and fixation of distal tibio-fibular syndesmosis are also added. However, the role of these additional procedures, which are not without their complications, is not well evaluated. A recent study had shown that correction of tibia vara without lengthening can be achieved without fibular osteotomy. However, use of distal tibio-fibular syndesmosis fixation (either with a wire or a screw) remains controversial. We present our experience in treating Blount's deformity with circular frame without stabilization of distal tibio-fibular syndesmosis.
10 patients were treated at our tertiary referral centre between 2000 to 2010. There were 7 boys and 3 girls. Age at surgery ranged from 8 yrs – 15 yrs. The mean patient age was 11.5 yrs. Two patients were treated with Ilizarov frame and 8 with Taylor Spatial Frame. Indications for surgery were unacceptable deformity (varus and internal rotation), with or without shortening. Varus deformity ranged from 10 degrees to 40 degrees. All tibiae were lengthened and the range of lengthening was from 1cm to 3.5cm. Fibular osteotomy was carried out in all patients. Tibio-fibular syndesmosis was never stabilized distally. All the patients were encouraged to mobilise full weight bearing as soon as tolerated and all of them had gradual correction of deformity usually starting a week following the surgery.
We achieved target correction of varus, internal rotation and leg length discrepancy in all patients. The commonest hurdle was superficial pin tract infection which resolved with short courses of oral antibiotics. Follow up ranged from 6 months to 10 yrs. Clinical and radiological evaluation of ankle did not show any abnormality in all these cases.
Satisfactory correction of Blount's disease (tibia vara and leg length discrepancy) can be achieved with circular frame without the stabilization of distal tibio-fibular syndesmosis.
