Bone void filler materials for augmentation in comminuted fractures: a comprehensive review

Comminuted fractures, characterized by multiple bone fragments, present significant challenges in orthopedic surgery. Effective treatment often requires augmentation techniques to enhance fixation stability and promote bone regeneration. This review explores the application of bone void filler materials, including autografts, allografts, polymethyl methacrylate (PMMA), and synthetic bone substitutes such as calcium phosphate ceramics and bioactive glass, in managing comminuted fractures. Autografts are the gold standard due to their superior osteogenic potential but are limited by donor site morbidity and availability. Allografts mitigate these issues but face concerns regarding immunogenicity and reduced biological activity. PMMA, widely used for structural augmentation, provides immediate stability but suffers from thermal necrosis, polymer shrinkage, and cytotoxic risks. Synthetic bone substitutes, including calcium phosphate cement and bioactive glass, offer promising alternatives by promoting bone integration while reducing complications associated with traditional grafts. However, their mechanical limitations and their artificial nature leave room for improvement. The review highlights recent advancements in biomaterial modifications to improve degradation rates, osteointegration, and mechanical resilience, such as composite materials and ion-doped bio ceramics. Despite these innovations, a gap remains in developing an ideal augmentation material that combines structural integrity with bioactivity. Future research should focus on integrating bioactive elements with load-bearing capabilities to optimize patient outcomes in comminuted fracture management.