GRADUAL CORRECTION OF PERIARTICULAR LOWER LIMB DEFORMITIES IN CHILDREN USING THE 8-PLATE: THE ALDER HEY EXPERIENCE

Abstract

Gradual correction of periarticular deformities has necessitated the application of external fixators to accomplish the task. By contrast, such deformities when treated by acute correction are most often stabilised using internal fixation. Hemi-epiphyseal arrest, by stapling or transphyseal screw is a disadvantage by being an irreversible process which has to be delayed until later childhood. This study describes the preliminary results of using an alternative internal device which corrects angular deformity by acting as a tension band on one side of the growth plate.

Twenty nine consecutive patients with significant coronal plane deformities in the lower limb were treated using the guided growth technique. This was accomplished through the extra-periosteal application of a 2-hole plate and screws (the 8-plate, Orthofix SRL, Verona). The plate was left in-situ and the patient monitored at regular intervals until the desired correction of the mechanical axis was accomplished. Plate removal was undertaken if the child was not skeletally mature at completion of treatment.

Eighteen males and 11 females completed treatment and had their plates removed. The age of patients ranged from 5 to 14 years (average 11.5 years). There were 23 patients with genu valgum deformity with an average deformity of 9.8 degrees, and 6 patients with genu varum deformity with an average deformity of 29.9 degrees. The follow up period averaged 12.5 months from plate removal. The average duration of correction was 15.8 months. The overall rate of correction was 0.87 degrees per month. Two complications were recorded: plate migration in one patient and deep infection in another patient. We had one case of rebound deformity.

The guided growth technique using the 8-plate is a simple and safe procedure for the treatment of lower limb angular deformity which produces temporary physeal arrest.