Abstract
Introduction
Congenital posteromedial bowing of tibia (CPMBT) is characterized by a decreasing deformity and an increasing limb shortening. Our series compares the duration and complications of lengthening in younger vs older children.
Materials and Methods
We studied 28 tibial lengthenings in 23 patients, divided into two equal groups of 14 segments: group-A ≤5 years (preschool) and Group-B >5 years. We measured preoperative (bo) and postoperative (po) sagittal, coronal, and oblique plane deformities, limb length discrepancy (LLD), amount of lengthening (AmtL), percentage lengthening (%L), external fixator duration (EFD) and external fixator index (EFI). Complications were graded by Lascombes’ criteria, results by ASAMI Bone score.
Results
Mean age= 8.8 ± 7.1 years; mean follow-up= 7.9 years. Group-A had significantly greater bo-sagittal, coronal, and oblique plane deformities. LLD (3.4 cm in group-A vs. 4.1 cm in group-B) was similar in both. LLD at maturity (LLDM) by multiplier method ranged 4.4–9.5 cm in group-A and 2.5–9.7 cm in group-B. Though AmtL (3.5 cm and 4.1 cm) was similar in both, %L was 24% in group-A and 15.7% in group-B (p=0.002). EFD (116.6 days) and EFI (33.7 days/cm) were lesser in group-A vs group-B (200.3 days, p=0.001; 50.2 days/cm, p=0.01). Lascombes’ criteria were fulfilled in 11/14 lengthenings in group-A vs. 3/14 in group-B. ASAMI bone score was good and excellent in both groups (p=0.44).
Conclusions
Younger children with large deformities and LLDM could be safely lengthened with lesser external fixator duration and complications than in older children.