Severity, distribution and postoperative therapy are not predictors of return to work in western performance horses...

(1) To evaluate the ability of western performance horses diagnosed with chondromalacia to return to performance; Specifically, the relationship between the grade of chondromalacia and the horses' ability to resume work; (2) To determine the impact of postoperative therapy on clinical outcomes.

Retrospective case series.

Horses (n = 34).

Records of western performance horses with lameness localized to the stifle that underwent subsequent arthroscopy with chondromalacia as the most significant diagnosis were reviewed. Chondromalacia was surgeon-graded as slight, mild, moderate, or marked. Three evaluated categories of postoperative intra-articular therapy included: (1) bone marrow derived mesenchymal stem cells, (2) equine amniotic allograft product or (3) none. Outcome was defined as returning to previous level of work on a numeric scale (1-10).

Chondromalacia and its degree of severity and focal vs. diffuse distribution identified arthroscopically did not show a significant association (p = .54, .40, respectively) or correlation (p = .18; R-value: 0.27) with the ability to return to athletic performance. The type of postoperative intra-articular therapy did not have any association with the horse returning to athletic work (p = .53).

A statistically significant association between severity, distribution or subsequent postoperative therapy for stifle chondromalacia and the ability to return to work was not observed.

Compared to previously published reports, this study demonstrated a 74% more favorable prognosis for returning to some level of athletic work despite only 44% of horses returning to their previous level of performance.