Results of screw epiphysiodesis for the treatment of limb length discrepancy and angular deformity.

The purpose of this study was to evaluate the technique of screw epiphysiodesis for effectiveness, predictability, and reversibility. We reviewed the cases of our first 60 patients (105 physes) treated with percutaneous screw epiphysiodesis or hemiepiphysiodesis. All cases were followed up to maturity or screw removal if growth remained after full correction. A total of 30 patients underwent the procedure for limb length inequality. Final inequality was compared with the predicted epiphysiodesis effect. A total of 30 patients (66 physes) underwent screw hemiepiphysiodesis for the correction of angular deformity. The degree of correction per month was calculated, the reversibility of the procedure was analyzed, and complications were evaluated. In the length group, at the end of treatment, the final limb length difference in the femur averaged 0.15 cm (SD, +/-0.37 cm) from the epiphysiodesis effect predicted by using the multiplier method. In the tibia, this difference was 0.05 cm (SD, +/-0.57 cm). In the angular group, the average correction in the distal femur was 6.91 degrees (SD, +/-3.75 degrees) or 0.75 degrees per month (SD, +/-0.45 degrees per month). In the proximal tibia, the average correction was 3.88 degrees (SD, +/-3.57 degrees) or 0.37 degrees per month (SD, +/-0.34 degrees per month). In all 13 cases where the screws were removed at the time of angular correction with significant growth remaining, growth resumed. Complications were minor and were related to incorrect placement of screws or minor hardware irritation. Percutaneous screw epiphysiodesis is a reliable, minimally invasive method with reliable results in both length and angular correction, with minimal morbidity, and with an acceptable complication rate.