Tissue‐engineered vascularized bone grafts: Basic science and clinical relevance to trauma and reconstructive microsurgery

Abstract

Bone grafts are an important part of orthopaedic surgeon's armamentarium. Despite well-established bone-grafting techniques, large bone defects still represent a challenge. Efforts have therefore been made to develop osteoconductive, osteoinductive, and osteogenic bone-replacement systems. The long-term clinical goal in bone tissue engineering is to reconstruct bony tissue in an anatomically functional three-dimensional morphology. Current bone tissue engineering strategies take into account that bone is known for its ability to regenerate following injury, and for its intrinsic capability to re-establish a complex hierarchical structure during regeneration. Although the tissue engineering of bone for the reconstruction of small to moderate sized bone defects technically feasible, the reconstruction of large defects remains a daunting challenge. The essential steps towards optimized clinical application of tissue-engineered bone are dependent upon recent advances in the area of neovascularization of the engineered construct. Despite these recent advances, however, a gap from bench to bedside remains; this may ultimately be bridged by a closer collaboration between basic scientists and reconstructive surgeons. The aim of this review is to introduce the basic principles of tissue engineering of bone, outline the relevant bone physiology, and discuss the recent concepts for the induction of vascularization in engineered bone tissue.

Delivery of Mesenchymal Stem Cells in Chitosan/Collagen Microbeads for Orthopedic Tissue Repair

“…Cell-based therapies for enhancing bone regeneration are being actively pursued, due to the limitations of current approaches in treating recalcitrant and poorly vascularized bone wounds (Rahaman et al, 2005; Johnson et al, 2011). However a purely cellular approach is not always appropriate for large bone defects, and as a result there has been increasing interest in using a combination of cells and matrix in these applications (Costa-Pinto et al, 2011; Gloria et al, 2010).…”

Preparation and Characterization of New Nano-Composite Scaffolds Loaded With Vascular Stents

“…Bone tissue engineering has provided a new way to repair, restore or regenerate large bone defects impaired by disease, injury, or age [1]. Constructs are typically created by seeding a scaffold with cells in vitro .…”

“…Finally, good mechanical properties are also essential requirements of an ideal scaffold in bone tissue engineering [2–5]. Currently, vascularization has been the greatest problem in the successful repair of large bone defects by bone tissue engineering [1,6]. Therefore, the construction and mechanical, biological and anti-clotting properties of scaffolds are of crucial importance.…”

Tissue Engineering of a Vascularized Bone Graft of Critical Size with an Osteogenic and Angiogenic Factor-Based In Vivo Bioreactor

“…Endocultivation of such a large bone graft is more feasible than the in vitro way, for vascularization of the large scaffold is technically much easier in vivo, taking advantage of the existing vasculature. 31,32 Endocultivation may be carried out either on bone defect sites or ectopically, for example, in muscles. Bone defect sites seem ideal for osteoprogenitors and bone-related factors may be mobilized from the neighboring bone stumps.…”