SUPPLEMENT ARTICLE Segmental Bone Defect Treated With the Induced Membrane Technique Sanjit R. Konda, MD,*† Mark Gage, MD,*† Nina Fisher, BS,*† and Kenneth A. Egol, MD*† Purpose: Posttraumatic bone defects in the setting of severe open injuries of the lower extremity present a signiﬁcant challenge for orthopaedic trauma surgeons. The induced membrane technique, also known as the Masquelet technique, has been shown to be generally successful in achieving bony union. This video demon- strates the use of the Masquelet technique for a large (18 cm) femoral defect. Methods: The Masquelet technique is a 2-stage process. The ﬁrst stage involves debridement of all devitalized tissue, using open reduction and internal ﬁxation, and placement of a cement spacer with or without antibiotics. In the second stage, which is performed at least 6 weeks after the ﬁrst, the spacer is removed and the resulting void is ﬁlled with bone graft. Results: This surgical case video reviews the relevant patient injury presentation, initial management, and indications for the Masquelet technique. The second stage of the Masquelet technique is featured in this video. Conclusions: The Masquelet technique is a generally reliable method for treating large segmental bone defects. In addition, this relatively simple technique is suitable for both infected and non- infected cases. Key Words: Masquelet, induced membrane, bone defect Video available at: http://links.lww.com/JOT/A35. (J Orthop Trauma 2017;31:S21–S22) C ritical-sized bone defects after musculoskeletal trauma can be challenging to adequately treat. However, the Masquelet technique represents a limb-salvaging technique with a relatively high success rate. 1 The Masquelet technique, also known as the induced membrane technique, is a 2-stage procedure. The ﬁrst stage requires stabilization of the defect and placement of a cement spacer, and for the second stage, which is performed 4–6 weeks later, the spacer is removed and bone grafting is performed. 2,3 During the time between the ﬁrst and second stage, a periosteal membrane will form around the cement spacer and will be ﬁlled with bone graft during the second stage. 4 The formation of the periosteal membrane will help prevent bone resorption after graft place- ment and secrete growth factors to promote bone formation. 4 This Supplemental Digital Content 1 (see video, http:// links.lww.com/JOT/A35) will demonstrate the second stage of the Masquelet technique. The patient is a 34-year-old man who sustained an open 3A right femur fracture after a motor vehicle collision. The patient was initially debrided multiple times and placed in an external ﬁxator. He was left with a large segmental defect of his femoral shaft, approximately 18 cm in length, extending into his distal metaphysis. Injury radiographs demonstrate segmental bone loss with extensive comminution. For reconstruction, the patient is indicated for the Masquelet procedure. After multiple debridements of the open fracture site, it was felt that the wound bed was clean. At approximately 2 weeks after the injury, the patient underwent the ﬁrst stage of the induced membrane technique. At this time, his femoral shaft fracture was treated with a locking condylar plate and intramedullary ﬁxation with a retrograde nail. Given the large segment defect, it was felt that combining a nail and plate ﬁxation at this stage would provide sufﬁcient stability to the construct to allow immediate weight-bearing after the second stage of the induced membrane technique. At this setting, a cement spacer made of polymethyl methacrylate was placed into the segmental defect and around the intramedullary nail. The cement spacer will both inhibit ﬁbrous tissue growth and maintain dead space volume until the reconstruction stage of the procedure. 5 Before the second stage, serum markers for inﬂamma- tion had normalized. To begin the second stage, iliac crest bone graft is collected from the patient’s contralateral hip. 2 Iliac crest bone graft is considered the gold standard in non- union treatment, and its osteogenic and osteoconductive prop- erties are important for promoting bone formation in large defects. 6 The skin and subcutaneous tissue is incised and the interval between the hip abductors and abdominal wall musculature is developed. Once the iliac wing is exposed, osteotomes are used to create a trapdoor conﬁguration of the inner table, allowing for ease of access to the cancellous autograft. Iliac crest bone graft is collected using Accepted for publication May 9, 2017. From the *Department of Orthopaedic Surgery, NYU Hospital for Joint Dis- eases, New York, NY; and †Jamaica Hospital Medical Center, Queens, NY. None of the authors have ﬁnancial or institutional disclosures to report related to this video. K. A. Egol is a consultant to, and receives royalties from, Exactech. He receives royalties from Slack Inc & Lippincott. He receives grant support form Orthopaedic Research and Education Foundation. There was no source of funding for this video. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www.jorthotrauma.com). Reprints: Kenneth A. Egol, MD, 301 East 17th St, New York, NY 10003 (e-mail: Kenneth.Egol@nyumc.org). Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved. DOI: 10.1097/BOT.0000000000000899 J Orthop Trauma  Volume 31, Number 8 Supplement, August 2017 www.jorthotrauma.com | S21 Copyright Ó 2017 Wolters Kluwer Health, Inc. Unauthorized reproduction of this article is prohibited.