Limits...
Evaluation of a biodegradable graft substitute in rabbit bone defect model.

Yang X, Li Y, Huang Q, Yang J, Shen B, Pei F - Indian J Orthop (2012)

Bottom Line: There was no significant difference between groups A and B.These findings demonstrated that the novel biodegradable copolymers can repair large areas of cancellous bone defects.With its controllable degradation rate, it suggests that CS/PAA may be a series of useful therapeutic substitute for bone defects.

View Article: PubMed Central - PubMed

Affiliation: Department of Orthopaedics, West China Hospital, Sichuan University, Chengdu, China.

ABSTRACT

Objective: To evaluate a new biodegradable copolymer calcium sulfate/poly amino acid (CS/PAA) as a graft substitute for the repair of the surgically created cancellous bone defects in rabbits and its biological properties in vivo.

Materials and methods: Cancellous bone defects were created by drilling holes in the unilateral lateral aspect of the femoral condyle of New Zealand white rabbits. Three groups were assigned: Group A rabbits were grafted with 80% CS/PAA and group B rabbits were grafted with 95% CS/PAA as two treatment groups; group C was sham-operation control group. To study the osteogenic capability in vivo, specimens were harvested at 4, 8, 12, and 16 weeks after implantation and were evaluated by gross assessment, X-ray, histological examination, and histomorphometry. In order to identify the molecular mechanism of bone defect repair, the expression of bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) was detected using Western blot at 4 weeks.

Results: Group A and group B showed more vigorous and rapid repair leading to regeneration of cancellous bone than sham-operation control group on gross observation, radiology, and histomorphometry. There was no significant difference between groups A and B. Morphological observation and histological examination showed that the copolymers degraded in sync with the new bone formation process. The expression of BMP-2 and VEGF in implantation groups was higher than that in control group by western blot.

Conclusion: These findings demonstrated that the novel biodegradable copolymers can repair large areas of cancellous bone defects. With its controllable degradation rate, it suggests that CS/PAA may be a series of useful therapeutic substitute for bone defects.

No MeSH data available.


Related in: MedlinePlus

X-ray images according to the three groups and time points (a, b, c at 4 weeks and d, e, f at 16 weeks) are presented here. Demonstrate the differences in the cacellous bone defect repair of each group, with group A(80% CS/PAA) and group B(95% CS/PAA) show more vigorous and rapid repair than group C(control group)
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3377135&req=5

Figure 4: X-ray images according to the three groups and time points (a, b, c at 4 weeks and d, e, f at 16 weeks) are presented here. Demonstrate the differences in the cacellous bone defect repair of each group, with group A(80% CS/PAA) and group B(95% CS/PAA) show more vigorous and rapid repair than group C(control group)

Mentions: After 4 weeks of operation, X-ray analysis demonstrated high levels of bone formation in defects grafted with 80% CS/PAA and 95% CS/PAA, obvious high-density spots of regions were observed, and the defect margins became irregular. In the control group, bone defect did not show any appreciable bone formation and the defect margins were smooth. At 8 weeks after the operation, in groups A and B, the representative radiographs revealed signs of bone repairing, while bone defect was clearly visible in the control group. At 12 weeks after surgery, most of the regions with bone defects could not be observed in groups A and B and one specimen of both the treatment groups even showed completely repaired bone defect, while the defect was still visible in the control group. At 16 weeks after surgery, the boundary between the newly formed and normal bone almost disappeared and the bone defects were totally repaired in groups A and B. Whereas in the control group there was only a small amount of new bone formed in the defects and the cavity in bone defect region was still visible in all specimens at 16 weeks [Figure 4]. There was no significant difference between groups A and B in bone repair at each time point after the operation.


Evaluation of a biodegradable graft substitute in rabbit bone defect model.

Yang X, Li Y, Huang Q, Yang J, Shen B, Pei F - Indian J Orthop (2012)

X-ray images according to the three groups and time points (a, b, c at 4 weeks and d, e, f at 16 weeks) are presented here. Demonstrate the differences in the cacellous bone defect repair of each group, with group A(80% CS/PAA) and group B(95% CS/PAA) show more vigorous and rapid repair than group C(control group)
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3377135&req=5

Figure 4: X-ray images according to the three groups and time points (a, b, c at 4 weeks and d, e, f at 16 weeks) are presented here. Demonstrate the differences in the cacellous bone defect repair of each group, with group A(80% CS/PAA) and group B(95% CS/PAA) show more vigorous and rapid repair than group C(control group)
Mentions: After 4 weeks of operation, X-ray analysis demonstrated high levels of bone formation in defects grafted with 80% CS/PAA and 95% CS/PAA, obvious high-density spots of regions were observed, and the defect margins became irregular. In the control group, bone defect did not show any appreciable bone formation and the defect margins were smooth. At 8 weeks after the operation, in groups A and B, the representative radiographs revealed signs of bone repairing, while bone defect was clearly visible in the control group. At 12 weeks after surgery, most of the regions with bone defects could not be observed in groups A and B and one specimen of both the treatment groups even showed completely repaired bone defect, while the defect was still visible in the control group. At 16 weeks after surgery, the boundary between the newly formed and normal bone almost disappeared and the bone defects were totally repaired in groups A and B. Whereas in the control group there was only a small amount of new bone formed in the defects and the cavity in bone defect region was still visible in all specimens at 16 weeks [Figure 4]. There was no significant difference between groups A and B in bone repair at each time point after the operation.

Bottom Line: There was no significant difference between groups A and B.These findings demonstrated that the novel biodegradable copolymers can repair large areas of cancellous bone defects.With its controllable degradation rate, it suggests that CS/PAA may be a series of useful therapeutic substitute for bone defects.

View Article: PubMed Central - PubMed

Affiliation: Department of Orthopaedics, West China Hospital, Sichuan University, Chengdu, China.

ABSTRACT

Objective: To evaluate a new biodegradable copolymer calcium sulfate/poly amino acid (CS/PAA) as a graft substitute for the repair of the surgically created cancellous bone defects in rabbits and its biological properties in vivo.

Materials and methods: Cancellous bone defects were created by drilling holes in the unilateral lateral aspect of the femoral condyle of New Zealand white rabbits. Three groups were assigned: Group A rabbits were grafted with 80% CS/PAA and group B rabbits were grafted with 95% CS/PAA as two treatment groups; group C was sham-operation control group. To study the osteogenic capability in vivo, specimens were harvested at 4, 8, 12, and 16 weeks after implantation and were evaluated by gross assessment, X-ray, histological examination, and histomorphometry. In order to identify the molecular mechanism of bone defect repair, the expression of bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) was detected using Western blot at 4 weeks.

Results: Group A and group B showed more vigorous and rapid repair leading to regeneration of cancellous bone than sham-operation control group on gross observation, radiology, and histomorphometry. There was no significant difference between groups A and B. Morphological observation and histological examination showed that the copolymers degraded in sync with the new bone formation process. The expression of BMP-2 and VEGF in implantation groups was higher than that in control group by western blot.

Conclusion: These findings demonstrated that the novel biodegradable copolymers can repair large areas of cancellous bone defects. With its controllable degradation rate, it suggests that CS/PAA may be a series of useful therapeutic substitute for bone defects.

No MeSH data available.


Related in: MedlinePlus