Palmar-plantar axial sesamoidean approach to the digital flexor tendon sheath in horses

A palmar-plantar axial sesamoidean (PAS) approach to the digital flexor ten don sheath in horses is described and compared with a more conventional pro ximolateral (PL) approach to the tendon sheath. The number of successful te ndon sheath injections, number of attempts required to access the tendon sh eath, time required to complete the injection, evidence of gross injury to the soft tissues, and number of limbs With subcutaneous deposition of contr ast material were recorded and compared between the PAS approach and the PL approach to the digital flexor tendon sheath. The PAS approach provided re liable access to the tendon sheath and took fewer attempts and significantl y less time than the PL approach. Anatomic landmarks for the PAS approach i nclude the neurovascular bundle and the palmar border of the midbody of the lateral proximal sesamoid bone. The PAS approach offers a rapid, reliable, and technically simple option for synoviocentesis of the digital flexor te ndon sheath in horses.