Nova proposta de bloqueio anestésico dos nervos metatársicos plantares medial e lateral de equinos

Abstract

This study introduces a new approach for perineural block anesthesia of the medial and lateral plantar metatarsal nerves in horses, aiming to improve diagnostic accuracy while minimizing excessive handling and the risk of iatrogenic injury. Pelvic limbs from six mixed breed Equus caballus specimens were used. Based on a topographic anatomical study of the plantar nerve distribution, two cadaveric techniques for nerve blocks were developed. When the horse is standing, the recommended technique involves inserting the needle bilaterally, 1.5 cm perpendicular to the foot, starting from the distal ends of the II and IV metatarsal bones. Alternatively, with the limb lifted and the metatarsophalangeal joint flexed, the needle can be introduced obliquely, 1.5 cm proximally from the distal ends of the II and IV metatarsals, at a 45° angle relative to the foot’s longitudinal, approximately 0.5 cm lateral to the II metatarsal and 0.5 cm medial to the IV. Based on the above, the proposal to adopt the blockade of the medial and lateral plantar metatarsal nerves distally (with the limb bearing weight or suspended), between the tendon of the deep digital flexor muscle and the metatarsal interosseous muscle (metatarsal suspensory ligament), represents a contribution to the diagnosis and treatment of hoof disorders in horses.