What area is targeted when performing a hanging drop technique for an epidural?

• A. A lumbar joint
• B. The last movable joint of the tail
• C. The sacroiliac joint
• D. The middle of the spine

Answer: (B)

The hanging drop technique for epidural placement is specifically aimed at the last movable joint of the tail. This technique involves the use of a syringe filled with anesthetic and a drop of fluid that is hung above the animal's body, allowing gravity to create tension on the spinal cord. By targeting the last movable joint of the tail, the veterinarian can access the epidural space more accurately, as this area corresponds to the sacral region of the spine where the spinal canal is more accessible, particularly in ruminants and other large animals.

This location is ideal for epidural anesthesia because the epidural space is typically located near the caudal end of the vertebral column in these animals, making it a suitable site for achieving anesthesia of the pelvic and hind limb regions. The anatomical landmarks around the tail's joint assist in ensuring proper needle placement and effective anesthetic delivery, thus enhancing the success rate of the procedure.