INTRAARTICULAR ANESTHESIA OF THE DISTAL INTERPHALANGEAL JOINT ALLEVIATES LAMENESS ASSOCIATED WITH THE NAVICULAR BURSA IN HORSES

Objective- To determine if intra-articular anesthesia of the distal in terphalangeal joint could alleviate lameness associated with the navic ular bursa in horses. Study Design- Experimental investigation. Animal s- Six clinically normal horses. Methods- Lameness was induced in each horse by injecting either the left or right front navicular bursa wit h 5 mg of amphotericin-B. Forty-eight hours later each horse was video taped walking and trotting before, and 5, 30, and 60 minutes after inj ecting the distal interphalangeal joint of the treated limb with 5 mL of 2% mepivacaine hydrochloride. All video recordings were then rereco rded onto master tapes in a random sequence. Four clinicians, unaware of the animal identity related to observation time or limb treated, in dependently viewed these tapes and graded the lamenesses. Results- The re was a significant reduction in lameness 5 and 30 minutes after anes thetic was injected into the distal interphalangeal joint. Lameness sc ores 60 minutes after anesthetic administration were not significantly different than baseline values. Gross pathological examination confir med marked inflammation of the treated navicular bursae and normal app earance of the distal interphalangeal joints. Conclusions- Intra-artic ular anesthesia of the distal interphalangeal joint can alleviate lame ness associated with the navicular bursa. Clinical Relevance- Intra-ar ticular anesthesia of the distal interphalangeal joint is not specific only for lameness originating in the distal interphalangeal joint. (C ) Copyright 1997 by The American College of Veterinary Surgeons.