Induced Membranes—A Staged Technique of Bone-Grafting for Segmental Bone Loss A Report of Two Cases and a Literature Review By Colin Yi-Loong Woon, MBBS, MRCSEd, MMed(Surg), MMed(Ortho), Keen-Wai Chong, MBBS, MRCS(Edin), MMed(Ortho), FRCS(Edin)(Ortho), and Merng-Koon Wong, MBBS, FRCS(Glasg), FAMS Investigation performed at the Department of Orthopaedic Surgery, Singapore General Hospital, Singapore D iaphyseal defects too long to be bridged by cancellous bone graft require complex reconstruction. Distrac- tion osteogenesis requires specialized equipment, has a steep learning curve, and is plagued by attendant pin-site complications and nonunion 1,2 . Vascularized bone, such as from the fibula, requires microsurgical anastomoses (free), or is limited by pedicle length (pedicled), and has attendant donor- site morbidity (both free and pedicled) 1,3 . The French technique of bone-grafting within induced membranes, otherwise known as the Masquelet technique, offers a viable alternative with minimal complications 4,5 . In this technique, a cement spacer is placed in a posttraumatic bone defect. Its presence serves a twofold function of preventing fibrous ingrowth into the bone gap, and inducing the forma- tion of specialized tissue or so-called induced membranes around it. Bone graft placed within this tube of induced membranes incorporates into functioning bone. We present the case of a patient with diaphyseal bone loss and the case of a patient with epimetaphyseal bone loss, both with ongoing bacterial contamination, successfully treated by this procedure. Both patients were informed that data con- cerning the case would be submitted for publication, and they consented. Case Reports C ASE 1. A twenty-year-old woman was struck by an auto- mobile while crossing the road. She sustained an open (Gustilo-IIIB) diaphyseal fracture of the left tibia (AO-OTA 42-C3) with marked loss of the soft-tissue envelope over the medial, anterior, and posterior aspects of the leg 6 . The wound was d´ ebrided on admission, and immobilization was achieved with an external fixator (Fig. 1). Two additional surgical d´ ebride- ments were necessary to ensure complete removal of extensive road debris contamination and to prepare the wound bed for future soft-tissue coverage. The defect was eventually covered with a vascularized rectus abdominis muscle flap six weeks later. Her recovery was complicated by wound infection with Klebsiella pneumoniae and Escherichia coli, both sensitive to imipenem. She was referred to our institution six months after the original injury with an infected tibial nonunion. Radiographs revealed a mid-diaphyseal defect of the left tibia measuring Fig. 1 Case 1. Radiographs showing an open (Gustilo-IIIB) diaphyseal fracture of the left tibia (AO-OTA 42-C3) stabilized with external fixation. Disclosure: The authors did not receive any outside funding or grants in support of their research for or preparation of this work. Neither they nor a member of their immediate families received payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. 196 COPYRIGHT Ó 2010 BY THE J OURNAL OF BONE AND J OINT SURGERY,INCORPORATED J Bone Joint Surg Am. 2010;92:196-201 d doi:10.2106/JBJS.I.00273