Outcomes of diode laser-facilitated ankylosis of the distal tarsal joints in horses: A retrospective study of 64 cases.

Objective: To evaluate the outcomes of diode laser-facilitated (DLF) ankylosis using different surgical techniques to treat distal tarsal osteoarthritis (OA) in horses.

Study design: Retrospective cohort study.

Animals: A total of 64 client-owned horses with distal tarsal OA treated with DLF ankylosis between 2011 and 2021 in a referral hospital were included.

Methods: DLF ankylosis techniques included: intra-articular diode laser (L), diode laser with periarticular drilling (L + D) and diode laser with cuboidal bone fenestration (L + F). Horses requiring a second surgery formed a fourth group (T). Outcome was assessed through client telephone surveys. Preoperative variables and surgical technique were assessed using logistical regression and OR models.

Results: A total of 64 horses met the inclusion criteria, and data was collected at a median follow-up time of 5 years (interquartile range [IQR]: 3-8 years). Improvement in lameness was observed in 83% (53/64) of horses, with 64% (39/61) returning to their previous level of athleticism. Sex significantly influenced outcome with males more likely to return to athleticism (p = .03, OR: 4.25). The return to previous level of athleticism for L, L + D and L + F was 67.9%, 50% and 66.7%, respectively. A smaller proportion of horses treated with L + D and L + F required additional surgical intervention compared to L (0%, 0%, and 20.8%, respectively).

Conclusion: DLF ankylosis offered a reliable treatment for distal tarsal OA in horses. Incorporating cuboidal bone fenestration provided good athletic outcomes while reducing the need for reintervention.

Clinical significance: DLF ankylosis offers a less invasive alternative to treat distal tarsal OA in horses with good athletic outcomes.