with a simultaneous increase in bone biomarkers [91, 92]. It has also been shown to have analgesic properties in some studies, but not in others [93]. There are some indications that ESWT can promote osteogenesis in horses [94] and that the mechanism may be induction of bone microfracture [95]. However, there is no evidence that ESWT can enhance fracture healing in horses.
Vibration therapy has been introduced to the equine market. In humans and experimental animals, the tendency is for bone healing to be improved in individuals with osteoporosis [96]. Although it has been suggested for equine rehabilitation purposes (Chapter 15) [97], its use to stimulate bone healing is questionable.
Hyperbaric oxygen therapy has been advocated to stimulate bone healing, but systematic reviews of the therapy have been inconclusive [98]. Considering the cost and need to transport the animal, it is unlikely to be clinically viable.
Conclusions
Bone healing is a complex paradigm, and thorough understanding of the process is necessary in order to make sound clinical judgements when managing fracture cases. An understanding of the healing process is also necessary as new techniques and medications become available. In human medicine, the ‘diamond concept’ has been proposed as a means to follow fracture healing (Figure 6.4). This addresses all the various factors that influence fracture healing, including the osteogenic cell population, osteoinductive stimulants, osteoconductive matrix, mechanical stability, vascularity and host factors. These guidelines should all be considered when managing fractures in horses.
Figure 6.4 The diamond concept for fracture repair demonstrating the key elements involved in the complex organization of bone healing.
Source: Based on Giannoudis et al. [23].
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