Equine Veterinary Journal Early View October 2015
By Heather Ferguson
Association between sesamoiditis, subclinical ultrasonographic suspensory ligament branch change and subsequent clinical injury in yearling Thoroughbreds
Plevin, S., McLellan, J. and O’Keeffe, T.
This prospective study aimed to investigate the associations between radiographic signs of sesamoiditis, ultrasonographic signs of suspensory ligament branch desmitis and subsequent clinical suspensory ligament branch injury (SLBI).
Before commencing training, 50 yearling Thoroughbreds from a single training facility were evaluated. Radiographic changes in sesamoid bones were graded on a scale of 0 to 5: Changes of Grades 2-5 were considered as possibly significant sesamoiditis. Ultrasonographic changes in the forelimb suspensory ligament branches were graded from 0 to 3, with Grades 2-3 considered as possibly significant. Further imaging was performed only if clinical SLBI occurred over the course of the subsequent 9 months.
The prevalence of Grade 2-5 sesamoiditis in initial radiographs was 20.5% (Observer 1) and 23% (Observer 2) of all 200 sesamoid bones assessed. The prevalence of Grade 2-3 suspensory ligament branch change was 18.5% (Observer 1) and 23% (Observer 2). Once adjustments were made for interobserver differences, there was a significant association between Grade 2-5 sesamoiditis and Grade 2-3 suspensory ligament branch injury.
28% of sesamoids with Grade 2-5 sesamoiditis also had Grade 2-3 suspensory ligament branch change of Grade 2-3, compared with 4% of sesamoids considered to be normal. Eight horses developed clinical SLBI, of which 5 had Grade 2-5 sesamoiditis and Grade 2-3 suspensory ligament branch change at initial imaging assessment. When considered separately from each other, both Grade 2-5 sesamoiditis and Grade 2-3 suspensory ligament branch change were significant risk factors for subsequent SLBI. When these occurred concurrently, there was a significantly increased risk of clinical SLBI.
There is an association between sesmoiditis and suspensory ligament branch changes. There is also a relationship between these conditions and subsequent clinical suspensory ligament branch injury, especially when these findings occur concurrently.