Background: Autogenous bone graft is the gold standard bone graft material. However, due to limitations of supply and morbidity associated with autograft harvest, various bone substitutes have been considered. This article aims to review the properties of the bone graft and various bone substitutes currently available in orthopedic surgery. Main body: Synthetic bone substitutes consist of hydroxyapatite, tricalcium phosphate, calcium sulfate, or a combination of these minerals. Synthetic porous substitutes share several advantages over allografts, including unlimited supply, easy sterilization, and storage. However, they also have some disadvantages, such as brittle properties, variable rates of resorption, and poor performance in some clinical conditions. Recently, attention has been drawn to osteoinductive materials, such as demineralized bone matrix and bone morphogenetic proteins. Conclusion: Despite tremendous efforts toward developing autograft alternatives, a single ideal bone graft substitute has not been developed. The surgeon should understand the properties of each bone graft substitute to facilitate appropriate selection in each specific clinical situation.

Objectives: To introduce a modified operative technique for minimally invasive plate osteosynthesis (MIPO) for acute displaced humeral shaft fractures and to evaluate the clinical and radiological outcomes. Design: Prospective clinical series study. Setting: University hospital. Patients: Twenty-one patients with acute displaced humeral shaft fractures were treated by MIPO with a modified fracture reduction technique. Intervention: A narrow 4.5/5.0-mm locking compression plate was applied to the anterior aspect of the humerus. Fracture reduction and manipulation were performed using a plate and drill bits. Main Outcome Measurements: The operating time, time to union, humeral alignment, and functional outcome of the shoulder and elbow joints were evaluated using the University of California Los Angeles shoulder score and Mayo elbow performance score. Results: No patient experienced a neurological complication. Bony union was obtained in 20/21 patients at a mean 17.5 weeks postoperatively. Eighteen patients had excellent and 3 patients had good results in the University of California Los Angeles score. The average Mayo elbow performance score was 97.5. Two patients were converted to an open reduction during operation due to a failure of MIPO. There was 1 nonunion and 1 malunion in this series. Conclusions: Although the MIPO technique for humeral shaft fractures is technically demanding, satisfactory clinical outcomes in terms of bony union and shoulder and elbow function can be obtained using the modified fracture reduction method. Potential postoperative complications, such as malreduction and nonunion, must be considered. Appropriate surgical indications, a thorough understanding of the neurovascular anatomy and skillful surgical technique, are needed to reduce potential complications. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.