Lamellar Pathology with Cushing’s

This investigation examined hoof tissues from horses affected by pituitary pars intermedia dysfunction (PPID or Cushing’s disease) with the hypothesis that pathologic changes consistent with laminitis would be found whether or not the animals showed clinical signs of laminitis. Tissues from 26 horses were examined including PPID affected horses with and without laminitis and controls. The length, width and appearance of primary and secondary epidermal lamellae were compared between the affected and the control horses.

The PPID animals with laminitis all had signs of insulin resistance and abnormal lamellar pathology including increased length and width of the lamellae, abnormal keratinization, epidermal bridging between lamellae, acute lamellar tearing and cell death. The horses with PPID but not laminitis didn’t have these changes. The authors concluded that regardless of the relationship between PPID and insulin resistance, it may only be the very high insulin levels not the PPID itself that are associated with the lamellar pathology and laminitis.

— Karikoski et al. 2014 EVJ;in press.

X-Rays of Sidebones

A retrospective case series characterized the radiographic appearance of sidebones of 386 feet of 271 horses with foot pain presenting to a referral equine hospital. Ossification of the cartilages was graded from 0 to 5 (only those scoring ≥ 2 were included in the study) and the presence of modeling, “adaptive changes” and fractures were recorded.

Fractures, modeling, adaptive changes and an abnormal shape of the ungular cartilages were all associated with an increased degree of ossification, which seems to…