Autografts and Bone Graft Substitutes
DNB Orthopaedics • May 2024 • Paper I • 10 Marks
Introduction
Bone grafting is used to promote bone healing, fill osseous defects, restore structural continuity and augment fusion. A successful graft may provide one or more of three important biological properties:
Osteogenesis
Living osteogenic cells within the graft directly produce new bone.
Osteoinduction
Growth factors recruit and differentiate host mesenchymal cells into osteoblasts.
Osteoconduction
A three-dimensional scaffold permits vascular and cellular ingrowth.
Autologous cancellous bone remains the biological benchmark because it possesses osteogenic, osteoinductive and osteoconductive properties.
A. Autograft
An autograft is bone harvested from one site and transplanted to another site in the same individual.
It may be used as:
- Cancellous graft
- Corticocancellous graft
- Cortical structural graft
- Vascularized bone graft
- Bone marrow aspirate / aspirate concentrate as a cellular adjunct
Possible Sites of Autograft Harvest
| Site | Type of Graft | Common Use / Pearl |
|---|---|---|
| Anterior iliac crest | Cancellous / corticocancellous / tricortical | Common and versatile; good quantity and structural graft possible |
| Posterior iliac crest | Large-volume cancellous / corticocancellous graft | Often provides greater volume than anterior crest |
| Proximal tibia | Cancellous graft | Useful for lower-limb procedures; avoids separate pelvic donor site |
| Distal femur | Cancellous graft |