Comparative outcomes of Adam Frame and Ilizarov external fixator in pediatric lower limb deformity correction

To compare the clinical and radiological outcomes of the computer assisted octopod external fixator [Adam Frame (AF)] and the conventional Ilizarov external fixator (IEF) in pediatric and adolescent patients undergoing lower limb deformity correction and lengthening.

This retrospective comparative study included 48 patients (< 18 years, 69 extremities) treated between 2009 and 2015 at two tertiary orthopedic centers. Patients were divided into AF (25 patients, 35 extremities) and IEF (23 patients, 34 extremities) groups. Demographic data, deformity characteristics, correction parameters, indices, and complications were analyzed. Primary outcomes included correction angles, external fixation indices, and complication rates.

The mean age at surgery was 12.0 years in both groups (AF range 9-14, IEF range 5-14; p = 0.309). Sex distribution was also similar (AF: 14 males, 11 females; IEF: 13 males, 10 females; p = 1.000). Femoral involvement was more common in the IEF group, while tibial involvement was common in the AF group (p = 0.046). Sagittal plane deformities were more frequent in the AF group (34.29% vs. 5.88%; p = 0.005). The sagittal correction angle (p = 0.034) and daily lengthening rate (0.80 vs. 0.70 mm/day; p = 0.038) were slightly higher in the IEF group.

Both AF and IEF are effective for pediatric deformity correction and lengthening. The IEF technique achieved greater sagittal correction and slightly faster lengthening. However, AF facilitates multiple adjustments, which can improve outcomes in complex tibial or sagittal-dominant deformities.