Though equine veterinarians routinely radiograph fetlocks when diagnosing lameness, there is not a significant correlation in the severity of changes in the fetlock and lameness in Western performance horses, according to Gabrielle Solum, DVM, a third-year Sports Medicine Resident at Colorado State University.
In her presentation at the 2023 American Association of Equine Practitioners Convention, Solum stated that pathology in the fetlock leads to lameness in Thoroughbreds but less is known about that link in Western performance horses.
To explore the connection between radiographic changes and lameness, Solum reviewed radiographs from a single private practice over a 10-year period, according to EquiManagement. If a horse’s baseline lameness improved more than 70% after intra-articular blocking of the fetlock joint, the case was included in the study. Ultimately, 173 horses were included.
“Lameness, flexion and effusion grades were recorded, and radiographs were evaluated for the presence, severity and location of pathology,” reports EquiManagement. “A boarded equine radiologist assigned each case an overall radiographic score, which Solum’s team compared to the lameness grade to find significant correlations.”
Out of 101 complete radiographs, only 90 were considered acceptable. Out of those 90, the average lameness score was 2.2 out of five. The most common radiographic abnormalities observed were distal cannon bone sclerosis, periarticular osteophytes, soft tissue swelling, P1 sclerosis and subchondral bone defects, says EquiManagement.
Though Solum found that the severity of the radiograph score did not correlate with the degree of lameness, certain pathologies were associated with increased lameness, such as joint space narrowing, subchondral bone cysts and P1 demineralization.
“Western performance with lameness localized to the fetlock likely have radiographic changes, especially chronic exercise-induced remodeling. Although degree of lameness did not correlate with severity of radiographic changes, lameness grade was significantly higher when certain radiographic findings are present,” Solum says.
Learn more about Solum’s presentation on EquiManagement.
