# Tibial lengthening with LRS fixator in a pediatric patient with congenital anterolateral bowing: A case report

## TL;DR

A 9-year-old boy with congenital tibial bowing successfully underwent tibial lengthening using an LRS fixator, achieving 3 cm lengthening without complications.

## Contribution

This case demonstrates the safe and effective use of LRS fixator for limb lengthening in pediatric patients with open growth plates.

## Key findings

- 3 cm tibial lengthening was achieved using an LRS external fixator with no complications.
- The External Fixator Index was 50 days/cm, and no neurovascular or infection issues occurred.
- The Paley Multiplier Method accurately predicted limb discrepancy and guided treatment planning.

## Abstract

Congenital anterolateral bowing of the tibia is a rare orthopedic condition that can lead to significant limb length discrepancy (LLD) during growth. Gradual limb lengthening with external fixation remains a reliable method to achieve limb equalization. LRS fixator offers a minimally invasive and adjustable treatment option for pediatric patients considering the growth potential.

We present the case of a 9-year-old boy with a known case of right-sided anterolateral bowing of the tibia, who presented with a 3 cm limb length discrepancy. The patient underwent minimally invasive corticotomy and tibial lengthening using a Limb Reconstruction System (LRS) external fixator. The postoperative period was free of complications with intended lengthening achieved.

Preoperative planning, growth potential and radiological assessment, and precise corticotomy are essential in limb lengthening procedures in pediatric patients. In this case, Paley multiplier method predicted a final discrepancy of about 6 cm at maturity which led to a decision to lengthen 3 cm at this stage and the External Fixator Index (EFI) was 50 days/cm, corresponding to five months of non weight bearing External Fixator use. No complications such as neurovascular compromise, pin tract infection, or joint stiffness were observed post-implant removal or during ROM exercises for rehabilitation.

Tibial lengthening using LRS is an effective method for managing moderate LLD in pediatric patients if the growth potential is adequately kept in account. Early intervention, meticulous surgical technique, and close follow-up are key factors for a successful outcome.

•Congenital anterolateral tibial bowing can cause in progressive limb length discrepancy in pediatric patients.•Gradual tibial lengthening was done with a monolateral LRS external fixator after precise preoperative planning.•Paley Multiplier Method was used to estimate final discrepancy and guide lengthening plan.•3 cm tibia lengthening was achieved with an External Fixator Index of 50 days/cm and no complications.•Case highlights safe application of distraction osteogenesis in pediatric patients with open growth plates.

Congenital anterolateral tibial bowing can cause in progressive limb length discrepancy in pediatric patients.

Gradual tibial lengthening was done with a monolateral LRS external fixator after precise preoperative planning.

Paley Multiplier Method was used to estimate final discrepancy and guide lengthening plan.

3 cm tibia lengthening was achieved with an External Fixator Index of 50 days/cm and no complications.

Case highlights safe application of distraction osteogenesis in pediatric patients with open growth plates.