Scintigraphy is an advanced imaging modality used to evaluate certain abnormalities of the skeleton. It uses radioactive tracers that allow the identification of changes in bone metabolism before they become visible on radiographs – for example, for identifying hairline fractures. It can identify problems in any part of the skeleton, but is especially useful in areas where clinical examination including diagnostic analgesia is often difficult, such as the pelvis and back.
How it works
The horse receives an intravenous injection of the radioactive substance Technetium, which acts as a ‘bone tracing’ agent. The bone scan camera is positioned next to the horse and is able to detect areas of increased bone turnover known as ‘hot spots’. It is the most sensitive method for the detection of fractures, inflammation, and infection and it shows pathology earlier than any other method.
Horses of any age and size can have a bone scan, including foals, broodmares and stallions. The dose of radiation is harmless to the horse's general health. The scan takes between 1-3 hours, depending on the area of interest, and does not require a general anaesthetic, though the horse cannot be discharged until the following day, when it is no longer radioactive.
When is scintigraphy indicated?
In most cases a bone scan forms part of a wider orthopaedic evaluation. Our clinicians will review the case history, the results of other tests and clinically examine your horse prior to the scan. Scintigraphy is useful in cases where:
- An area of lameness has been localised but no abnormalities have been detected using radiography or ultrasound
- Nerve blocks have not revealed the site of lameness
- There is multi-limb lameness
- In severe lameness where a fracture is suspected
- Screening the whole skeleton is indicated in poor performance cases with no overt lameness
- An area cannot be easily penetrated by radiography (e.g. the back and pelvis)
What happens after the bone scan?
Our specialist clinicians will discuss the bone scan findings with the client and the referring veterinary surgeon. We will also discuss if further tests or treatments are necessary prior to discharge from Rossdales. Following a bone scan horses commonly undergo:
- Nerve and joint blocks
- Joint medications
The complex nature of many bone scan cases means horses are usually resident with us for 2-3 days, sometimes longer. We understand that it can be stressful for the client having their horse away from home and our staff will provide frequent updates.