Surgical Technique for Revision of the Distally Migrated Fassier–Duval Femoral Rod in Osteogenesis Imperfecta: A Case Report

<b>Background/Objectives</b>: Managing long bone fractures and deformities in osteogenesis imperfecta (OI) with telescoping rods is a common but challenging procedure. A rare complication is the distal migration of the rod's proximal female component, which complicates standard revision surgery. This article aims to describe a surgical technique for the revision of a distally migrated Fassier-Duval (FD) femoral rod. <b>Methods</b>: We present the case of an 8-year-old girl with OI type IV who experienced distal migration of her right femoral FD rod-the surgical technique involved extracting the rod retrogradely through the fracture/osteotomy site. We used a trephine to remove surrounding bone within the canal, thereby preserving the critical bone stock in the greater trochanter needed for secure fixation of the revision implant. <b>Results</b>: The distally migrated female component was successfully removed through the trephined canal with a combination of axial traction and rotational force. The proximal bone stock was preserved, allowing for the stable placement of a revision FD rod. <b>Conclusions</b>: The retrograde trephine technique is a viable and effective strategy for revising a distally migrated telescoping rod in patients with OI. This approach prioritizes the preservation of proximal bone stock, which is crucial for the stability and longevity of the revision implant.