REASONS FOR PERFORMING THIS STUDY: Intra-articular ethanol has been described to promote distal tarsal joint ankylosis. Its use and results in clinical cases affected by osteoarthritis (OA) have not been reported.
To describe and evaluate the results of treatment of distal tarsal joint OA by facilitated ankylosis stimulated by intra-articular ethanol injection.
Twenty-four horses met the inclusion criteria of tarsometatarsal and centrodistal joint OA diagnosed by a positive response to intra-articular analgesia, radiographic evaluation and recurrence of lameness ≤ 4 months after intra-articular medication with a corticosteroid. Horses were sedated and, following a radiographic contrast study of the tarsometatarsal joint, medication with 2-4 ml of either 100% pure ethanol (G100) or a 70% ethanol (G70) solution was applied. Horses were classified as improved based on a 50% reduction from initial lameness grade combined with an increase in exercise level.
Of the 24 horses included in this study, 20 had the treatment performed bilaterally and 4 unilaterally. All horses were available for initial follow-up examination and 21 for a second one 6-9 months after treatment. This represented a total of 44 treated limbs and 35 available for long-term follow-up. Of these, 21/35 (60%) were considered improved, which corresponds to 11/21 horses (52%). Of 21 horses, 4 (19%) deteriorated and 2 of these developed significant complications related to treatment.
Ethanol should be considered in the treatment of certain cases of distal tarsal joint OA. The importance of performing an adequate radiographic contrast study of the tarsometatarsal joint prior to treatment is highlighted.
Distal tarsal joint ankylosis with ethanol should be considered a safe and economic treatment in cases of distal tarsal joint OA that fail to show long-term improvement with intra-articular corticosteroid treatment.