Delivering a growth factor in a dissolvable carrier at the site of a bony fracture results in accelerated healing when compared to untreated horses, and it is as effective as treating horses with a bone graft post-fracture, researchers recently reported.

Fractures are an important problem in athletic horses. According to a group of researchers from the University of Wisconsin-Madison, fractures account for more than two-thirds of fatal musculoskeletal injuries in Thoroughbred racehorses and are associated with huge economic losses due to prolonged recovery periods. As such, novel techniques for fracture repair resulting in accelerated healing are of particular interest.

The growth factor in this study, recombinant human bone morphogenetic protein-2 (rhBMP-2), is known to initiate bone formation. When combined with a dissolvable carrier such as calcium phosphate, rhBMP-2 can be delivered directly to the fracture site and will maintain sufficiently high concentrations for a long enough period to signal the migration and multiplication of bone-forming cells at that site.

To study the effect of rhBMP-2 on bone healing, researchers created a fracture in either the second or fourth metatarsal bones. The bones were treated with injection of rhBMP-2, an autogenous bone graft from the horse’s own tibia, or were left untreated