NM (Nuclear Medicine / Scintigraphy / Bone Scan)

Scintigraphy provides a full-body view of the horse’s skeleton. After a warm-up period, the horse is injected with a radiopharmaceutical (Tc99m-HDP) that binds to the mineral phase of bone (hydroxyapatite). A high-resolution gamma camera then captures areas of increased radiopharmaceutical uptake, known as “hotspots” or IRU (Increased Radiopharmaceutical Uptake), indicating heightened bone activity.

• Common indications include:
• Performance issues
• Neck, back, or pelvic concerns
• Unlocalized or shifting lameness
• Suspected stress fractures (e.g., pelvic fractures)
• Evaluation of multiple limb regions

Scintigraphy is performed with the horse standing and is especially valuable in identifying hidden or early-stage injuries that may not yet be visible via other imaging methods. However, because IRU only indicates an area of increased activity and not the specific underlying cause, additional targeted imaging—such as radiography, CT, or MRI—is often necessary to further characterize the lesion.

Following the administration of the radiopharmaceutical, a mandatory 24-hour isolation period is required for safety and regulatory reasons, in accordance with radiation protection guidelines.