TIBIAL LENGTHENING AND CORRECTION DEFORMITY IN CHILDREN USING SHEFFIELD RING FIXATOR.

Abstract

Aim: To review the results of tibial lengthening and deformities correction in children using the Sheffield Ring Fixator.

Materials and methods: We have reviewed, retrospectively, 25 patients (average 12.2 years old) who underwent predominantly lengthening of the tibia using the Sheffield Ring fixator.

The average follow up was 25.7 months. For logistic regression analysis the patients were binary coded into two groups: those with a good outcome (BHI< 45 days/cm) and those with a poor outcome (BHI> 45 days/cm). Various factors which may influence the out come were then analysed.

Results: The most common indication for tibial lengthening in our series was for fibular hemimelia in 6 patients and achondroplasia in 4 and growth arrest secondary to trauma in 3. The mean lengthening of 48.1 mm (25–76). The mean accuracy of lengthening achieved was 85%.

11 patients had foot plate extension, and 5 had cross knee extension for unstable knee. 10 patients had bifocal osteotomy, and 8 patients had spontaneous SLR for femoral lengthening or correction.

The mean bone healing index was 49 days/cm (20–95). The mean maximum correction in any one plane was 150 (3–40), the site of the osteotomy was mainly metaphyseal at an average of 25% of the tibial length.

There were 5 grade II complications, 9 grades I complications and one type III complication. Thirteen patients had grade I pin site infection, three had grade II and 12 had no pin site problems.

A moderately strong relationship was identified between the BHI and a number of variables such as complications, maximum correction and pin site infection grade.

The analysis of the factors which may influence the BHI suggested a correlation between increasing angular correction and poor out come BHI.

Conclusion: In tibial lengthening in children there is a correlation between increasing angular correction and poor out come BHI