Equine distal limb diagnostic anaesthesia: (2) Intrasynovial anaesthesia

Intrasynovial anaesthesia is appropriate when trying to localise lameness further following perineural anaesthesia, or if localising signs implicate the synovial cavity as the source of lameness. A thorough understanding of the complex interactions of intrasynovial local anaesthetic between neighbouring synovial structures, particularly between the distal interphalangeal joint and navicular bursa, is important when performing the procedure, as are skin preparation and personal hygiene when introducing a needle into a synovial cavity. This article, the second in a two-part series on diagnostic anaesthesia of the distal limb in horses, reviews the basic techniques for intrasynovial distal limb anaesthesia. The first article (Barker 2016) discussed the basic principles of diagnostic anaesthesia and perineural techniques.