Updated: March 26, 2012 at 12:00 am
Izzy the kitten came in as an emergency with her owner and the owner’s 5-year-old daughter, Clarissa. They had had the kitten for about a month and the girl was so enamored of the little cat that she wanted to pick her up and haul her around everywhere.
Clarissa’s parents could see that having a small, somewhat uncoordinated child haul the kitten around in her arms was likely to lead to trouble, so they made the rule that Clarissa was only to pet and play with the kitten when sitting down, and she was not to carry the kitten in her arms and walk around.
Clarissa tried to follow the rules, but the temptation was just a little too much at one point, and as she was struggling to hoist a wiggling Izzy and walk up the stairs at the same time, she got her feet tangled up and fell down on the cat, breaking Izzy’s font leg just below the elbow.
Every fracture is a unique entity and presents it’s own challenges for repair. Due to advances in orthopedic surgery, we now have the option to surgically repair all sorts of fractures with plates and screws or pins and wires or even more complicated forms of fixation like external skeletal fixators. Not all general practitioners have the equipment or experience for these repairs, but everyone will know where to send their more-complicated fracture repairs when needed. Often surgical repair is the best option, but the cost could run into the thousands of dollars.
The one type of fracture stabilization that almost all veterinarians will have available is the good, old-fashioned cast. A cast can be an effective and comparatively inexpensive way to get some fractures to heal, but what casts may save in expense they sometimes cost in headaches for maintenance and management.
Casts are appropriate only for certain simple types of fractures. To stabilize a broken bone, the cast has to immobilize the joint above and below the break. That means that casts are used only on fractures below the elbow on front legs and below the stifle (knee) on hind legs. Even then, not all fractures in those locations are suitable for treatment with a cast.
Fractures of the femur (thigh bone) and humerus (upper arm bone) cannot be stabilized with a cast because it is impossible to get a cast up high enough to immobilize the hip or the shoulder. The top of the cast will end up at about the level of the fracture and the rest of the cast will act as a fulcrum to bend the bone at the fracture site. All that motion will make sure that the bone will never heal. A broken femur or humerus will have a better chance of healing if you do nothing to it than if you place a cast or splint on it.
Even though they are technically below the elbow, broken forelegs on tiny dogs are notorious for not healing in a cast, so primary surgical repair — like a plate — is usually a better choice.
In veterinary medicine, we ask our casts to do a lot more than they were really designed to handle. Our patients have to walk on them, and they are often allowed to run around like knuckleheads chasing squirrels with them, even when the instructions were to keep the animal quiet.
Many cats will stop at nothing to figure out how to hook the edge of a cast on the leg of the couch and yank their leg out of the horrible contraption. Dogs seem to think that casts are a new type of chew bone that has been affixed to their leg for hours of uninterrupted gnawing pleasure.Our patients can develop pressure sores from slipping casts and rashes from dirt that has gotten down into the cast while the patient was being “kept quiet” outside. All of this activity leads to much higher maintenance, more frequent replacement of casts, and a higher rate of complications then your average human doctor has to deal with.
Izzy got a cast, which she didn’t appreciate very much. But because she was young, and because cats are such good healers, her broken bone was well mended at the six-week mark, about two weeks earlier than we usually take a cast off. It was a good thing for all of us, because she had just figured out how to pry the cast off by hooking the top on the edge of the refrigerator and pulling as hard as she could — and she was certainly ready to put that new skill to use on any future casts that might be applied to her.
Anne Pierce is a Colorado Springs veterinarian and co-owner of High Plains Veterinary Hospital, a Colorado Springs small-animal clinic. Reach her at