Fetlock region block sites, horse

Sites for intra-articular and perineural blocks of the fetlock region in a horse. 1. Fetlock joint, intra-articular block: A 21‑gauge, 3.8‑cm (1½‑inch) needle is inserted to its hub directly perpendicular to the long axis of the limb, through the collateral sesamoid ligament, into the space between the condyle of the third metacarpal/tarsal bone (MT/MCIII) and the articular surface of the sesamoid bone. The limb must be held and the fetlock flexed to create enough space to insert the needle. The joint can be accessed more easily by inserting a needle into the dorsal pouch or palmar/plantar pouch of the joint; however, a needle inserted into the joint at these sites is not as stable and can be dislodged during injection. 2. Low six-point nerve block: This image shows the lateral three sites; the medial three sites are mirror images of these. In the forelimb, the two most dorsal injection sites are always omitted, and many clinicians also omit them in the hindlimb.