Malposition of the Resorbable Sheet in Medial Orbital Wall Fractures: Frequency and Techniques for Prevention

The aim of this report is to discuss malposition of the resorbable sheet in medial orbital wall fractures and how to prevent this problem. After making an incision through the skin and orbicularis oculi muscle, a skin-muscle flap was elevated just superficial to the orbital septum, extending to the arcus marginalis. Dissection was extended just below the anterior lacrimal crest to increase the exposure. Fracture site in medial orbital wall was visualized. A resorbable sheet (poly- l -lactide, d -lactide sheet, 0.5-mm thickness) was trimmed and molded in an L shape, with the vertical portion used to cover the medial wall defect and the horizontal portion for stability in the orbital floor. An extended part, measuring roughly 1 cm, was bent across on the infraorbital rim, and this part was fixed with absorbable screws to prevent the sheet from crumpling. After the molded plate was put in position, the periosteum and skin were closed. From 2011 to 2021, the authors operated on 152 orbital floor or medial wall fractures. Among 152 patients who underwent surgery to reconstruct orbital floor or medial wall fracture, of whom 27 patients had both floor and medial wall fractures, the authors experienced 2 cases of medial orbital wall fractures where the resorbable sheet was malpositioned, requiring reoperation. To prevent malposition of the sheet in medial wall reconstruction, the inferomedial angle of the vertical portion and the horizontal portion of the sheet should be about 135°. Before fixing the sheet on the bony part, a complete tension-free forced-duction test is mandatory.