Radiographs provide limited information about soft tissue, such as tendons, ligaments, or structures inside the joints, which are often the source of lameness. Diagnostic nerve and joint blocks . These analgesic techniques are perhaps the most important tools used to identify the location of lameness. Working from the foot up, the veterinarian temporarily deadens sensation to specific segments of the limb, one joint at a time, until the lameness disappears. This procedure isolates the area of pain causing the lameness.
Blocks can also help determine whether the condition is treatable.
Radioisotopes injected intravenously into the horse are concentrated in inflamed areas. These areas can be scanned with a gamma camera, providing an image of the trouble site. This procedure allows optical examination of internal joint tissues or tendon sheaths. It requires general anesthesia but may be the only way to define the damage. Some diagnoses can only be made with arthroscopy.