Bilateral Medial Femoral Condyle Flaps for Management of Secondary Robin Deformity: A Case Report

Abstract

Introduction:

Pierre-Robin Sequence (PRS) is characterized by micrognathia, glossoptosis, and airway obstruction, often requiring early surgical intervention. Multiple techniques have been described to treat the associated mandibular deformities, including mandibular distraction osteogenesis, bone grafting, and orthognathic surgery. In severe mandibular deficiency at skeletal maturity, a free vascularized bone transfer, most commonly a fibular flap, is often utilized. The medial femoral condyle (MFC) flap has been applied to mandible reconstruction but is thought to be limited in size and ability to confer cortical strength and structure. This report describes a case involving the use of 2 exceptionally large medial femoral condyle (MFC) flaps containing long cortical bone segments for bilateral reconstruction of the mandibular rami and condyles in a patient with severe micrognathia and PRS.

Methods:

We present a case of large (75 and 80 mm) MFC flaps and conventional orthognathic surgery in a 15-year-old patient with non-syndromic PRS, a history of multiple failed mandibular reconstructions, and bilateral congenital below-the-knee amputations.

Results:

The staged procedure was performed successfully with minimal donor-site morbidity. The patient tolerated the surgery well, with resolution of airway obstruction and improved mastication, swallowing, and speech. Initial postoperative imaging noted improved dentofacial and mandibular arch form. Over time, however, the patient developed a relapse of malocclusion, and subsequent imaging showed substantial resorption of bone, necessitating revision surgery.

Conclusion:

We describe the first reported case of bilateral (MFC) flaps containing long segments of cortical bone used for reconstruction of bilateral mandibular rami and condyles. While the patient experienced symptomatic improvement, recurrence of Class II occlusion and bone resorption was observed radiographically. Additional research is necessary to evaluate the viability of this technique as a potential option for large segment reconstruction of the mandibular ramus and condyle.