Background: Segmental long bone defects remain a formidable treatment challenge. All the existing standard treatment options have major limitations and often culminate in limb amputation or permanent functional deficits. We developed a novel, one-stage alternative treatment for segmental bone loss that utilizes the cylindrical titanium mesh cage (CTMC) in combination with bone graft, and have established its clinical merits in an initial clinical series. Shortly thereafter, Masquelet reported another new defect reconstruction technique that involves two-stage approach: first inducing biomembrane formation with a cement spacer, and subsequent spacer removal and bone grafting. Both the Masquelet and the CTMC techniques are based on the principle of graft containment to render optimal potential for graft to heal the defect; however, they differ in primary biological versus biomechanical functions provided by the containment. The Masquelet biomembrane containment, being a rich source of vascular supply and growth factors, creates an excellent biological milieu for graft, but requires an additional surgery and is associated with prolonged protected weight bearing until graft consolidation occurs. Conversely, the benefit of the CTMC technique is primarily the biomechanical support it provides for graft and the reconstructed extremity, thereby permitting immediate functional restoration without mobility or weight bearing restrictions during the bone healing process. Although both Masquelet and the CTMC techniques have been effective in the treatment of large segmental bone defects, there is no prospective, well-controlled study comparing their therapeutic efficacies for specific clinical indications.