https://www.oarsijournal.com/article/S1063-4584(02)90801-0/pdf

Articular cartilage repair: basic science and clinical progress. A review of the current status and prospects.

Autograft is considered ideal for grafting procedures, providing osteoinductive growth factors, osteogenic cells, and an osteoconductive scaffold. Limitations, however, exist regarding donor site morbidity and graft availability. Allograft on the other hand, posses the risk of disease transmission. Synthetic graft substitutes lack osteoinductive or osteogenic properties. Composite grafts combine scaffolding properties with biological elements to stimulate cell proliferation and differentiation and eventually osteogenesis. We present here an overview of bone grafts and graft substitutes available for clinical applications.

Bone substitutes: an update.

Several growth factors are expressed in distinct temporal and spatial patterns during fracture repair. Of these, vascular endothelial growth factor, VEGF, is of particular interest because of its ability to induce neovascularization (angiogenesis). To determine whether VEGF is required for bone repair, we inhibited VEGF activity during secondary bone healing via a cartilage intermediate (endochondral ossification) and during direct bone repair (intramembranous ossification) in a novel mouse model. Treatment of mice with a soluble, neutralizing VEGF receptor decreased angiogenesis, bone formation, and callus mineralization in femoral fractures. Inhibition of VEGF also dramatically inhibited healing of a tibial cortical bone defect, consistent with our discovery of a direct autocrine role for VEGF in osteoblast differentiation. In separate experiments, exogenous VEGF enhanced blood vessel formation, ossification, and new bone (callus) maturation in mouse femur fractures, and promoted bony bridging of a rabbit radius segmental gap defect. Our results at specific time points during the course of healing underscore the role of VEGF in endochondral vs. intramembranous ossification, as well as skeletal development vs. bone repair. The responses to exogenous VEGF observed in two distinct model systems and species indicate that a slow-release formulation of VEGF, applied locally at the site of bone damage, may prove to be an effective therapy to promote human bone repair.

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Vascular endothelial growth factor stimulates bone repair by promoting angiogenesis and bone turnover

A critical review of recombinant human bone morphogenetic protein-2 trials in spinal surgery: emerging safety concerns and lessons learned

Understanding and controlling the bone-implant interface

Many approaches are used to repair skeletal defects in reconstructive orthopaedic surgery, and bone grafting is involved in virtually every procedure. The type of bone graft used depends on the clinical scenario and the anticipated final outcome. Autogenous cancellous bone graft, with its osteogenic, osteoinductive, and osteoconductive properties, remains the standard for grafting. However, the high incidence of morbidity during autogenous graft harvest may make the acquisition of grafts from other sources desirable. The clinical applications for each type of bone graft are dictated by the structure and biochemical properties of the graft. An elegant cellular and molecular cascade follows bone transplantation. Bone graft incorporation within the host, whether autogenous or allogeneic, depends on many factors: type of graft (autogenous versus allogeneic, vascular versus nonvascular), site of transplant, quality of transplanted bone and host bone, host bed preparation, preservation techniques, systemic and local disease, and mechanical properties of the graft.

The biology of bone grafting.

Study design A retrospective chart review was conducted for 112 patients who underwent revision posterior lumbar spine decompression, fusion, and segmental instrumentation. Objective To ascertain factors predicting hospital stay, operative time, blood loss, and transfusion in patients undergoing revision posterior lumbar spine decompression, fusion, and segmental instrumentation. Summary of background data Posterior lumbar spine decompression and fusion with segmental instrumentation is a common procedure in the treatment of degenerative lumbar spine disorders. Many patients undergoing this procedure have had previous lumbar spine surgery, yet little is known about the factors predicting hospital stay, operative time, blood loss, and transfusion. Methods The charts of 112 patients (53 men and 59 women) with degenerative lumbar spinal stenosis who underwent revision surgery from March 1992 to June 1999 were reviewed. Their average age was 54 years (range, 27-84 years). All the surgeries included decompression and fusion with segmental instrumentation. The patients' demographics, comorbid conditions, factors related to previous lumbar spine surgery, diagnosis, number of levels fused, and preoperative hemoglobin and hematocrit were collected and used as the independent variables. Multiple regression analysis was used to ascertain factors predicting length of hospital stay, operative time, intraoperative blood loss, and transfusion. Results The mean length of hospital stay was 6 +/- 2.4 days, the operative time 280 +/- 62 minutes, the estimated intraoperative blood loss 1073 +/- 716 mL, and the total volume of blood transfused 1.04 +/- 1.17 U. For 63% of the patients, a blood transfusion was needed. Increasing age was the significant predictor for hospital stay (P Conclusions Number of levels fused and age seem to be the most significant factors predicting hospital stay, operative time, intraoperative blood loss, and transfusion in patients undergoing revision posterior lumbar spine decompression, fusion, and segmental instrumentation.

Factors predicting hospital stay, operative time, blood loss, and transfusion in patients undergoing revision posterior lumbar spine decompression, fusion, and segmental instrumentation.

https://www.orthopedic.theclinics.com/article/S0030-5898(05)70157-7/pdf

Bone growth factors.

https://www.orthopedic.theclinics.com/article/S0030-5898(03)00105-6/pdf

Safdar N. Khan

Papers

The biology of bone grafting.

Factors predicting hospital stay, operative time, blood loss, and transfusion in patients undergoing revision posterior lumbar spine decompression, fusion, and segmental instrumentation.

Bone growth factors.

Piriformis syndrome and low back pain: a new classification and review of the literature.

Clinical applications of bone graft substitutes.