The use of flexible intramedullary nails in limb lengthening.

INTRODUCTION: Lower and upper limb length discrepancy and deformity, congenital or acquired, are amongst the most common conditions in children for orthopaedic referral. Over the last twenty years, surgical techniques have evolved in an attempt to decrease Healing Index and minimise these complications. Areas covered: The flexible intramedullary nailing (FIN) is a minimally invasive intramedullary osteosynthesis. In combination with an external fixator, it is appropriated for pediatric bone lengthenings and lengthening of bones of small diameter in adults. In the study the Scopus and/or PubMed indexed publications about this combined technique were analyzed. Expert commentary: The use of titanium or stainless steel or hydroxyapatite-coated bent elastic nails is appropriate in limb lengthening for congenital and acquired limb length discrepancy. Hydroxyapatite-coated FIN should be applied for long-term reinforcement of lengthened bone in patients with metabolic bone disorders, skeletal dysplasias with compromised bone formation. Osteoinductive surface of nails is favorable for bone formation and as well as for stable position of nails without risks of migration in long-term follow-up. The FIN is an unique intramedullary fixation which respects the bone biology which is mandatory for a good bone consolidation.