Peroneus brevis tendon ‘turn down lengthening’ for reconstruction post resection of right lateral foot fibromyxoid sarcoma for child in early childhood – a case report and surgical technique

Abstract

Background: Low grade fibromyxoid sarcoma is rare in the paediatric age group. It is usually painless and slow growing but may display a relatively higher and atypical risk of metastasis. We describe such a case in the right foot involving part of the 5th metatarsal, cuboid, and peroneal tendons. We share a technique for reconstructing the peroneus tendons to restore normal gait and balance the hindfoot in a child. Case report: This is a child who presented with a painless right lateral border foot lump since 6 months of age. Open biopsy found this to be a low-grade fibromyxoid sarcoma. The child underwent wide resection of the lesion. Reconstruction to balance the hindfoot was done by peroneus brevis tendon ‘turn down lengthening’. At 5 years post-operation, he is able to walk, run and jump with no issues. He plays football and basketball without trouble. Conclusion: In conclusion, fibromyxoid sarcomas are rare tumours. In a growing child, the reconstruction of the peroneus brevis tendon by ‘turn down lengthening’ is a possible option to restore normal gait and maintain hindfoot balance.