Page 175 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

150 CHAPTER 1

VetBooks.ir 1.275

Fig. 1.275 Bone scintogram of an eventer that presented with a bilateral forelimb lameness and sore cannon
bones on palpation. Note the marked radiopharmaceutical uptake down the dorsal aspects of both dorsal third
metacarpal bones on the lateral and dorsopalmar views. (Photo courtesy Graham Munroe).

PALMAR CORTICAL STRESS FRACTURES Clinical presentation
The horse presents with an overt lameness often of
Definition/overview moderate nature. Heat/pain may be present, partic-
Stress fractures caused by abnormal bone loading in ularly on direct pressure over the medial head of the
the palmar aspect of the proximal third metacarpus/ suspensory ligament.
metatarsus (usually forelimb).
Differential diagnosis
Aetiology/pathophysiology Avulsion fracture.
Palmar cortical stress fractures usually occur in the
proximal third metacarpus/metatarsus in the region Diagnosis
of the attachment of the suspensory ligament (usu- Clinical signs may suggest injury in the proximal
ally medial side). Abnormalities range from stress metacarpal region. Diagnostic analgesia is impor-
reactions to a fulminant cortical fracture. tant in localizing lameness to this region but may