The bone scan reveals the changes in the metabolism of the bone more than actual changes in the bone structure. Bone scintigraphy compliments but does not replace survey radiography. The changes in scintigraphy usually proceed the changes noted on the x-rays since the bone's metabolism usually changes before the bone's structure changes. Scintigraphy is useful in the evaluation of patients with poorly localized lameness especially when x-rays are inconclusive. Small lesions can result in significant changes in the metabolism of the bone which is assessed through the images.
Bone scans are useful for diagnosing conditions such as infections, tumors, and arthritis.
The changes caused by these conditions are often seen on bone scans before they show on x-rays. Earlier diagnosis means earlier treatment, and increases the probability that the treatment will be more successful. Bone changes may be apparent on a bone scan, but the cause of the lesion may not be. In these instances, other diagnostic tests may be necessary. Its major value is in determining the extent of the gland involvement.