DE-EPIPHYSIODESIS OR CHONDRODIASTASIS

Abstract

Purpose: Physeal distraction can be used for the treatment of the consequences of epiphysiodesis bridges, correcting simultaneously angular deformations and length discrepancy.

Material and methods: Chondrodiastasis was performed in six children aged 13.1 years (range 10.4–15.7). The cause of the epiphysiodesis was trauma in three children (2 distal tibia, 1 distal radius), osteomyelitis in two (distal femur), and surgical sequela of a clubfoot (distal tibia). Mean follow-up was two years (18 months – 4 years). An Ilizarov device was used in four cases and an Orthofix in two.

Results: Limb length discrepancy was corrected in all cases. Angular correction was insufficient in two. Distraction was continued for four months (1–9) and total duration of treatment was 7.5 months (4–13). Minor complications were pin track infection (n=2) and joint stiffness (n=3). Major complications were one fracture of the femur on a pin site and premature closure of the growth cartilage treated by callotasis and one fracture after removal of the external fixator, treated by plaster cast immobilisation. The final outcome was good in both of these children.

Discussion: De-epiphysiodesis with surgical resection of the bony bridge can only be performed before a certain age (10–11 years) and the outcome in uncertain. The principle advantages of physeal distraction applied for angular deformation in growing patients is that it avoids the need for osteotomy and allows progressive correction. This noninvasive method allows angular correction in the upright patient, concomitant lengthening is also achieved. Chondrodiastasis makes an exact correction of the deformation without resection of the bony bride which can be ruptured by simple distraction. The fertility of the growth cartilage after distraction must be considered as lost so the amount of correction must be calculated on the basis of a complete and definitive postoperative epiphysiodesis.

Conclusion: Chondrodiastasis allows correction of acquired and predictable epiphysiodesis bridges at the apex of the deformation and without direct access. This method can be used for partial epiphysiodesis (less than 50%) in children who have not reached maturity. After distraction, the growth cartilage must be considered as definitively closed.