Thoracic trauma in newborn foals

Abstract

Summary In a report describing life ending fractures (255 horses) from the Livestock Disease Diagnostic Center, Kentucky (1993 and 1994), 32 foals had rib fractures. The purpose of our study was to examine the incidence of rib fractures in newborn foals on a Thoroughbred studfarm by physical and radiographic examination, to determine factors which may contribute to the problem and to document any clinical consequences. All foals (263) included were examined within 3 days of birth. The thoracic cage was palpated externally for abnormalities and all foals were placed in dorsal recumbency to evaluate thoracic cage symmetry. Radiographs were used to diagnose foals with thoracic cage asymmetry (TCA) and rib fracture (RF). A diagnosis of costochondral dislocation (CD) was made when no radiographic evidence of fracture was present but there was severe TCA. Fifty‐five foals (20.1%) had TCA (9 RF). One to 5 ribs were fractured on 9 of 40 radiographic studies. No consequences of the thoracic trauma was detected clinically, radiographically or ultrasonographically in this group of foals or at a 2‐ and 4‐week follow‐up examination. The percentage of foals with a history of abnormal parturition was higher in the TCA foals (15%) compared to the normal foals (6.8%). There were more primiparous dams in the TCA group than in the normal foal group. Fillies (56.6%) had a higher incidence of birth trauma than colts (43.4%). This study demonstrates that thoracic trauma is often present in newborn foals and may not always be of clinical significance. Dystocia foals and foals from primiparous mares should be considered high risk for thoracic trauma.

Rib osteomyelitis in three foals

“…Rib fractures in foals commonly occur at or near the costochondral junction of the cranial ribs, in particular ribs 3 to 8, with a left‐sided bias often documented 9–11,23 . Complications are usually related to laceration of organs by displaced fracture ends 11,12 and secondary osteomyelitis is uncommon.…”

“…The most frequently affected bones are the femur, tibia and third metacarpal/metatarsal bones, 5,6 with costal osteomyelitis infrequently reported 5–8 . Fracture of one or more ribs is a common pathological feature of thoracic trauma in neonatal foals 9 . Although such fractures may not be clinically significant, 9,10 rib fractures have been established as a significant cause of morbidity and mortality in foals 11,12 .…”

Respiratory disease in the neonatal foal

“…Costochondral dislocation was reported in 20% of foals at an Irish Thoroughbred farm (Jean et al 1996). Costochondral dislocation was reported in 20% of foals at an Irish Thoroughbred farm (Jean et al 1996).…”

Ultrasonographic Examination of the Equine Neonate

“…Rib fractures are a significant source of morbidity and fatality in some practices 9 and appear to be most common in thoroughbred foals, foals born to a primiparous mare, and foals delivered with human assistance, with or without dystocia. [10][11][12] The soft tissue structures inside the thorax are viewed in the spaces between the ribs. In neonates, thoracic contents are sensitively surveyed with a microconvex linear transducer operating at frequencies of 4 MHz to 8 MHz.…”

“…The author prefers to use a transducer with a microconvex footprint for surveying the organs inside the thorax and a linear transducer operating at 6 MHz to 10 MHz for imaging the ribs and other superficial structures. When a fracture is found, a higher frequency (8)(9)(10)(11)(12) can be used to view the site with maximal detail. Because of the tradeoff between detail and depth, the overarching principle of sonographic imaging is to use the highest available frequency that will penetrate to the depth necessary for any given tissue.…”