Biologic adjuvants and bone: current use in orthopedic surgery

Abstract

Normal bone healing is a complex process that eventually restores original structure and function to the site of trauma. However, clinical circumstances such as nonunion, critical-sized defects, systemic bone disease, and fusion procedures have stimulated a search for ways to enhance this normal healing process. Biologics are an important part of this search and many, including bone marrow aspirate concentrate, demineralized bone matrix, platelet-rich plasma, bone morphogenic proteins, and platelet-derived growth factor, are currently in clinical use. Many others, including mesenchymal stem cells, parathyroid hormone, and Nel-like molecule-1 (NELL-1) will likely be in use in the future depending on the results of preclinical and clinical trials.

Application of platelet-rich plasma with stem cells in bone and periodontal tissue engineering

“…As PRP is a good cell proliferator and BMPs are good osteogenic differentiators, it makes it feasible to administer them in conjunction with each other in order to increase the formation of bone in critical-sized defects. 252 Furthermore, PRP with the GF beads can be double encapsulated with cements like Nano calcium sulfate. The slow degradation rate of Nano calcium sulfate would enable the PRP to be released at the peak of bone formation thus increasing its efficiency for bone formation greatly in clinical studies.…”

Biologic Augmentation of Tibiotalocalcaneal Arthrodesis With Allogeneic Bone Block Is Associated With High Rates of Fusion

“…In addition, we sought to improve the osteoinductive and osteogenic properties of the allograft through the use of demineralized bone matrix cortical fibers and pelvic bone marrow aspirate concentrate, which stimulate the differentiation of pluripotent mesenchymal cells into mature osteoblasts and serve as a source of proteinaceous growth factors naturally present in bone (eg, BMP, TGF-β, VEGF, PDGF, IGF). 42,47 Hernigou et al 20 found that allografts charged with pelvic bone marrow–derived mesenchymal stem cells yielded superior bony growth when compared to uncharged allografts and even autografts, the gold standard. Moreover, charged allografts not only demonstrated histologic evidence of new bone formation at the periphery but also in the centroid region, suggesting that de novo osteogenesis was occurring throughout the entirety of the graft and not merely at the interface with recipient bone.…”

“…Given the significant morbidity and related patient dissatisfaction, surgical refinement and various biophysical agents have been explored as reconstructive adjuncts to TTC arthrodesis, with the goal of decreasing incidence of nonunion and lowering complication rates. 42 Structural allografts, when placed in osseous defects, have been shown to increase bone-on-bone contact and act as cellular scaffolds, enhancing TTC fusion via osteoconduction. 12,34,35 In addition, osteoinductive agents, such as demineralized bone matrix, bone marrow aspirate, and bone morphogenic proteins, promote healing by stimulating differentiation of mesenchymal progenitor cells into mature osteoblasts.…”

(ii) An update on fracture healing and non-union

“…Either bone marrow aspirate or platelet-rich plasma can be harvested and then injected around fracture sites, or mixed with other media to stimulate normal bone-healing biology. 55 Synthetic bone substitutes These are predominantly osteoconductive void fillers and include hydroxyapatite, tricalcium phosphate, calcium phosphate and calcium carbonate alone or in varying combinations. They show increased potential for use when combined with osteoinductive agents and when mixed with autograft or bone marrow aspirate.…”