A technique for creating critical-size defects in the metatarsus of sheep for use in investigation of healing of long-bone defects.
OBJECTIVE
To develop a technique for use in investigation of healing of long-bone defects by creation of a critical-size defect in the left metarsal III and IV bone (metatarsus) of sheep.


METHODS
18 healthy adult sheep.


METHODS
Sheep were allocated to 4 groups (3, 3, 5, and 7 sheep in groups 1 to 4, respectively). An ostectomy with various segmental length-to-diaphyseal diameter ratios (0.5, 1.0, 2.0, and 2.0 for groups 1 to 4, respectively) was performed on the left metatarsus of each sheep. The defect was left empty in sheep of groups 1, 2, and 3, whereas the defect was filled with a massive corticocancellous bone autograft in sheep of group 4.


RESULTS
All sheep tolerated the surgical procedure well and were able to use the affected limb the day after surgery. Radiographic and histologic examinations conducted 16 weeks after surgery revealed nonunion in all sheep of groups 1, 2, and 3, whereas consistent bone healing with abundant bone formation was observed in all sheep of group 4.


CONCLUSIONS
Analysis of these findings suggests that the sheep metatarsal model is a critical-size defect model with low morbidity. It should allow the assessment of new technologies for bone regeneration in conditions closely mimicking the clinical setting.


CONCLUSIONS
Use of this technique in sheep should be of benefit for the preclinical study of osteoconductive, osteoinductive, or osteogenic biomaterials for use in humans.
Viateau
Véronique
V
Laboratoire de Recherches Orthopédiques, Centre National de la Recherche Scientifique-Sciences pour l'Ingénieur, Faculté de Médecine Lariboisière Saint-Louis, Université Denis Diderot, Paris, France
Guillemin
Geneviève
G
Yang
Yu Chien
YC
Bensaid
Wassila
W
Reviron
Thierry
T
Oudina
Karim
K
Meunier
Alain
A
Sedel
Laurent
L
Petite
Hervé
H
D000818:Animals; D001861:Bone Regeneration / Q000502:physiology*; D018483:Diaphyses / Q000503:physiopathology / Q000601:surgery*; D004195:Disease Models, Animal; D005260:Female; D017102:Fracture Healing / Q000502:physiology*; D008682:Metatarsal Bones / Q000000981:diagnostic imaging / Q000502:physiology*; D008684:Metatarsus / Q000000981:diagnostic imaging / Q000293:injuries*; D008852:Microradiography / Q000662:veterinary; D012756:Sheep / Q000293:injuries* / Q000502:physiology; D013522:Surgery, Veterinary / Q000379:methods