Retrospective Analysis of Suspensory Ligament Branch Injuries in 70 Dressage Horses

There are no studies that have investigated factors influencing the outcome of dressage horses with suspensory ligament (SL) branch injuries. The aim was to determine if age, breed, work level, injury severity, anatomical localisation of injury, number of injured branches, periligamentous fibrosis, persistence of power Doppler signal or coexistent osteoarthritis of a metacarpophalangeal (MCP) or metatarsophalangeal (MTP) joint influenced the prognosis of 70 dressage horses. Outcome was defined as good (return to pre-injury level of work or higher), poor (return to a lower level of work) or retirement. Chi-squared or Fisher's exact test and the Kruskal-Wallis test were used to identify relationships between variables of interest and follow-up outcome. Follow-up outcome was good in 44/70 horses (62.9%), poor in 13/70 (18.6.%) and 13/70 horses (19.1%) were retired due to no response to treatment. Ultrasonographic lesion grade (p = 0.07), cross-sectional area (CSA) of the SL (p = 0.96), CSA of the lesion (p = 0.28) and the lesion CSA as a percentage of the SL CSA (p = 0.40) were not associated with outcome. Power Doppler signal was present in 75.8% of injured branches at the initial examination. The severity of power Doppler signal was not associated with outcome (p = 0.20); however, persistence of power Doppler signal was negatively associated with outcome (p < 0.001). Other variables did not influence the follow-up outcome. Early recognition of SL branch injury is likely to result in a more favourable outcome with appropriate treatment and management.