A comparative study of the correction of femoral deformity between the Ilizarov apparatus and Ortho-SUV Frame.

Purposes: This study compared the six-axis external fixator Ortho-SUV Frame (OSF) and the Ilizarov apparatus (IA) in femoral deformity correction. Our specific questions were: (1) which of the fixators (OSF or IA) provides shorter period of femoral deformity correction, and (2) which of the fixators (OSF or IA) provides better accuracy of correction.

Methods: We retrospectively analysed 123 cases of femoral deformities (127 femora): 45 (47) treated with OSF (20 male and 27 female) and 78 (80) with IA (53 male and 27 female). The average age in the OSF group was 34.6 (range, 18-66) and in the IA group 35.8 (range, 18-76). All the deformities were categorized according to the number of planes and deformity components as simple, middle and complex deformities.

Results: Elimination of simple deformities in the IA group took 58.3 ± 21.4 days, EFI 58.8 ± 39.8 days/cm, and lengthening was 4.6 ± 1.98 cm. Middle deformities were 71.3 ± 26.2, 61.9 ± 30.3 and 4 ± 2, respectively. In complex deformities we had 105.2 ± 21.8, 79.3 ± 35.4 and 3.2 ± 1.45, respectively. Normal alignment was achieved in 55.0% of cases in IA. In 45.0% of cases we had residual deformity. Elimination of simple deformations in the OSF group took 55.3 ± 12.8 days, EFI 47.5 ± 23 days/cm, and lengthening 4.5 ± 1.1 сm. Middle deformities were 43.6 ± 18.9, 59 ± 14.6 and 3.6 ± 2, respectively. In complex deformities we had 44.9 ± 11.5, 57.5 ± 9.4 and 3.6 ± 1.7, respectively. In the OSF group normal alignment was achieved in 85.1%. In 14.9% there was residual deformity.

Conclusion: Using OSF simplifies deformity correction and reduces its period by 2.3 times in complex deformities and by 1.6 times in middle deformities. Accuracy of correction with OSF was significantly higher than correction with IA.