Equine scintigraphy: basic principles and interpretation

Abstract

Bone scintigraphy is the only imaging technique able to demonstrate organ function rather than anatomical details. It involves intravenous injection of a radiopharmaceutical that binds to the bone structures and display alteration in osteoblastic activity. It is commonly used in horses presented for lameness investigation or poor performances, although the sensitivity of the technique in identifying the lesion causing lameness in poor performing sport horses was demonstrated to be low. Conversely, scintigraphy shows high sensitivity in detecting remodelling related to stress-related bone injury and stress fractures, which often occur in racehorses. It must be remembered, however, that the presence of increased radiopharmaceutical uptake does not necessarily indicate a lesion causing pain, and lameness and scintigraphy should be always used in conjunction with in-depth lameness investigation and, when possible, diagnostic analgesia.