Comparison of treatment indices associated with the correction and lengthening of deformities along various lower limb frontal plane directions.

PURPOSE: The Taylor spatial frame (TSF) provides higher precision in the dimensional correction of some lower limb deformities. However, no study to date has compared the osteogenesis outcome of correction and lengthening among various directions in the frontal plane. We examined the relationship between the external fixation index (EFI) and the direction of correction in the frontal plane.

METHODS

We classified 25 patients undergoing correction with the TSF into three groups: Group A (8 patients, varus deformity), Group B (6 patients, valgus deformity), and Group C (9 patients, non-correction in the frontal plane). We excluded patients who underwent chemotherapy, were converted to internal fixation, had infection or pseudarthrosis, and in whom the corrected gain was <2.4 cm.

RESULTS

No significant differences in age, sex, etiology of deformity, complication due to deformity in another plane, osteotomy distribution, TSF use duration, and correction distance were found. The average EFI was 83.4, 60.5, and 51.2 days/cm in Groups A, B, and C, respectively, with the EFI being significantly higher in Group A than in Group C (P < 0.05).

CONCLUSIONS

Osteogenesis of varus deformities was more prolonged than that of non-correction in the frontal plane. These results provide useful insights that can aid in minimizing complications due to external fixation and improving our understanding of the mechanism of osteogenesis in the tibia.