The ovariectomised sheep as a model for testing biomaterials and prosthetic devices in osteopenic bone: a preliminary study on iliac crest biopsies.
A histomorphometric and ultrastructural evaluation on sheep iliac bone was performed. Six sheep were ovariectomised (OVX Group) and 6 were left intact (Sham-aged, Control Group). An iliac crest biopsy was performed randomly in 6 animals at the beginning of the study, then, in all the animals, after 12 and 24 months. A significant decrease in trabecular bone volume, trabecular thickness (p<0.0005) and cell volume (p<0.005) was observed in OVX animals. A modest decrease in trabecular number and osteoid thickness together with an increase in trabecular separation were observed in OVX animals at 12 and 24 months. The osteoid volume showed a significant difference (p<0.05) between the groups. In OVX animals, at 12 months, Scanning Electron Microscopy revealed an enlargement of the trabecular space and a progressive replacement of bone matrix with adipose tissue. These signs were accentuated at 24 months. In conclusion, OVX sheep showed a loss of trabecular bone starting at 12 months after ovariectomy. The developed osteopenic state may be considered as a useful tool when doing research on biomaterial osteointegration.
Fini
M
M
Experimental Surgery Department, Rizzoli Orthopaedic Institute, Bologna, Italy. milena.fini@ior.it
Pierini
G
G
Giavaresi
G
G
Biagini
G
G
Mattioli Belmonte
M M
MM
Nicoli Aldini
N
N
Rocca
M
M
Martini
L
L
Giardino
R
R
D000704:Analysis of Variance; D000818:Animals; D001672:Biocompatible Materials; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D007085:Ilium / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning; D016348:Osseointegration; D015663:Osteoporosis, Postmenopausal / Q000473:pathology*; D010052:Ovariectomy; D019736:Prostheses and Implants; D012756:Sheep
D001672:Biocompatible Materials