Common long bone fracture in small animal practice--part 2.

Abstract

The small animal practitioner can expect to see many long bone fractures over the course of a career. For those who are equipped to manage these surgically, the challenge is to select the appropriate fixation hardware and surgical technique. For many who may be prepared to tackle some intramedullary pin and wire applications or feel comfortable with external coaptation, the trick is to identify which cases will lend themselves to these techniques and which need to be referred. For those who refer most or all such cases, an understanding of what fractures are commonly seen, how they can be managed, and what prognosis goes along with them can be helpful in counseling clients. An analysis of patient records from 282 long bone fractures managed surgically in our practice from September 1983 to December 2002 yielded some valuable information on the location and types of fractures seen most often. The femur is, by far, the bone that is fractured most often in the dog and cat, comprising almost half of all long bone fractures in some surveys (1,2). Forty-five percent (128/282) of our long bone fractures were femoral fractures, 26% (74/282) were tibial fractures. It is interesting to speculate why almost 3 of every 4 long bone fractures in small animals occur in the hind limb. It may be that these represent only those patients that survived the traumatic episode, so as to be treated surgically. It is likely that trauma significant enough to fracture bones in the cranial half of the animal would more frequently cause lethal trauma to the head or chest. Similar trauma to the caudal half of the animal would be less likely to produce life-threatening injury. It may also be that animals see impending trauma coming (automobiles) and, in their effort to flee, they expose their hindquarters to the major force of the impact. Fractures of the radius, ulna, or both were considered together since, concurrent fractures of both bones are seen in the vast majority of cases. These fractures accounted for 16% (46/282) of our cases. The humerus is the long bone that is fractured least often by all accounts (2) and was involved in 13% (36/282) of our cases. Parts 1 and 2 of this topic review the “top 5” categories of long bone fractures recorded in our survey. They are presented in reverse order of frequency of occurrence; nearly 80% of the long bone fractures fell into 1 of the 5 categories.