Novel microhydroxyapatite particles in a collagen scaffold: a bioactive bone void filler?
Frank G Lyons1, John P Gleeson, Sonia Partap
1Tissue Engineering Research Group, Department of Anatomy, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland.
Clinical Orthopaedics and Related Research
|January 4, 2014
Summary
A novel collagen-hydroxyapatite scaffold effectively heals bone defects, matching autograft performance without safety concerns. This bone graft substitute offers a promising alternative for segmental bone loss treatment.
Area of Science:
- Orthopaedic Surgery
- Biomaterials Science
- Regenerative Medicine
Background:
- Segmental bone loss presents a significant challenge in orthopaedic surgery.
- Current treatments like autografts have limitations, and recombinant human bone morphogenetic protein-2 (rhBMP-2) raises safety concerns.
- There is a critical need for effective, safe osteoinductive bone graft substitutes.
Purpose of the Study:
- To evaluate collagen-glycosaminoglycan (CG) scaffolds alone and with hydroxyapatite (HA) for bone defect healing in rabbits.
- To assess the efficacy of these scaffolds with and without low-dose rhBMP-2.
- To compare scaffold performance against autografts and empty controls.
Main Methods:
- A 15-mm radius defect model was used in New Zealand White rabbits.
- Treatments included collagen-hydroxyapatite (C-HA) and collagen-glycosaminoglycan (CG) scaffolds, with and without rhBMP-2.
- Radiographs, micro-CT, and histological analyses were performed at multiple time points up to 16 weeks.
Main Results:
- C-HA scaffolds with rhBMP-2 demonstrated the highest healing levels, completely filling defects with dense callus.
- CG scaffolds with rhBMP-2 and CG scaffolds alone showed significant healing, with nearly complete medullary canal formation at 16 weeks.
- C-HA scaffolds alone showed greater defect filling than CG scaffolds at 6 weeks.
Conclusions:
- The C-HA scaffold provides comparable healing to autografts and is a viable alternative to rhBMP-2 loaded scaffolds, addressing cost and safety issues.
- CG scaffolds may be suitable for low load-bearing defects, while C-HA scaffolds are indicated for load-bearing defects.
- rhBMP-2 loaded scaffolds show potential for treating established nonunion defects.
