Which of the following techniques allows for local anesthetic administration directly into a joint?

The technique that allows for direct local anesthetic administration into a joint is known as the intraarticular block. This method is specifically designed for delivering anesthetic agents directly into the joint space, facilitating pain relief in that area. Intraarticular blocks are commonly used in veterinary medicine for procedures that involve joint manipulation or surgery, helping to manage postoperative pain and discomfort.

In contrast, infiltration anesthesia involves injecting the anesthetic into the tissues surrounding a specific area, rather than directly into a joint. Similarly, a splash block typically refers to the application of anesthetic to a surgical site or wound, often after the incision has been made, but not directly into the joint space. A mental block, on the other hand, is a specific technique used to anesthetize the mental nerve in the jaw area and is not related to joint anesthesia. Therefore, the intraarticular block is the correct choice for administering local anesthetics directly into joints.