Recombinant human bone morphogenetic protein-2 in absorbable collagen sponge enhances bone healing of tibial osteotomies in dogs.
OBJECTIVE
To compare the efficacy of 2 doses of recombinant human bone morphogenetic protein-2 (rhBMP-2) on tibial osteotomy healing in dogs.


METHODS
Experimental, randomized complete block (n=7).


METHODS
Adult female dogs (n=21).


METHODS
Right midshaft tibial osteotomies were created and stabilized with a 1-mm gap using type I external fixators. Seven dogs were untreated controls and 14 with osteotomies were treated with either 0.05 or 0.2 mg/mL rhBMP-2 delivered in an absorbable collagen sponge (ACS). At 8 weeks, dogs were euthanatized and bones were mechanically tested and examined by microscopy.


RESULTS
Bone healing based on radiographic scoring, was significantly improved in dogs treated with 0.2 mg/mL of rhBMP-2 compared with the other groups; these tibiae were also significantly stronger and stiffer than 0.05 mg/mL rhBMP-2 and control osteotomized tibiae. Histologic scores were significantly better for 0.2 mg/mL rhBMP-2 group than 0.05 mg/mL rhBMP-2 group, but neither was significantly different from control.


CONCLUSIONS
rhBMP-2 in ACS at a concentration of 0.2 mg/mL improves healing of tibial osteotomies in dogs compared with untreated controls and 0.05 mg/mL rhBMP-2 based on force plate analysis and radiographic evaluation. This was not confirmed histologically but treated bones had improved mechanical properties at 8 weeks.


CONCLUSIONS
After a long bone fracture, dogs may face a long recovery period before full return of limb function. rhBMP-2, in association with good fracture fixation principles, may enhance bone healing in dogs with diaphyseal fractures.
Faria
Maria L E
ML
Comparative Orthopaedic Research Laboratory, Department of Medical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA.
Lu
Yan
Y
Heaney
Kathleen
K
Uthamanthil
Rajesh K
RK
Muir
Peter
P
Markel
Mark D
MD
D000818:Animals; D001672:Biocompatible Materials / Q000008:administration & dosage; D001843:Bone Cements; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000008:administration & dosage*; D003094:Collagen / Q000008:administration & dosage; D004285:Dogs / Q000601:surgery*; D005260:Female; D017102:Fracture Healing; D006801:Humans; D010027:Osteotomy / Q000295:instrumentation / Q000662:veterinary*; D011994:Recombinant Proteins / Q000008:administration & dosage; D013977:Tibia / Q000601:surgery*; D016212:Transforming Growth Factor beta / Q000008:administration & dosage*; D016896:Treatment Outcome
C525718:BMP2 protein, human; D001672:Biocompatible Materials; D001843:Bone Cements; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; D003094:Collagen