Hip replacements in dogs have improved through years
Q I have not owned a dog for the past 10 years. I lost my golden retriever, back then, to severe hip dysplasia. She was 9 years old and very overweight. I share the blame for that, but she really could not exercise because her hips had become so painful.
We considered a hip replacement then but because the risk of complications was so high, we decided against that. It was a very difficult decision to let her go. Now I have a Labrador retriever puppy.
So far so good on the hips, but if they do become a problem, has the procedure changed in the past decade that makes it a better option?
A: Fortunately, the answer to your question is yes. Improvements in the technique have provided far more flexibility, and customization to the individual patient, than ever before. These same changes have also dramatically reduced short- and long-term post-surgical complications. The time interval since you last investigated this procedure has allowed long-term observations, and statistical analysis, comparing various aspects of the procedures. This has allowed refinements and fine tuning, which has further improved outcomes.
I (Henri Bianucci) remember the first time I was scrubbed in on a hip replacement, and they were fairly new at that time, was when I was an intern at the University of Missouri.
In 1995. The stress surrounding the entire procedure was oppressive. So much so, that a student hit the deck mid-way. She fainted and fell onto the table, contaminating the entire field. To make matters worse, there were two veterinarians visiting from Japan, who were observing the procedure.
For posterity, they gad their video cameras set up, recording every aspect of the procedure, including the fainting episode.
These early procedures were, primarily, what are known as "cemented" hips. This means that the metal implants were secured into the bone with an acrylic bone cement.
The hip is a "ball and socket" joint. The ball was part of a metal stem, which was inserted into the thigh bone. Next, a plastic cup, or socket, was placed where the original hip socket was located, and it was secured with cement as well. The positioning of the implants is critical to the success of the procedure.
The most stressful points in the surgery are when positioning the implants in the cement. This is because the cement hardens quickly, so the implants had to be placed accurately, and quickly. If they were in the wrong position after the cement had solidified, you had real problems.
In the same procedure where the student fainted, the cement was inserted into the thigh bone (femur) and the surgeon then asked for the metal stem. It was nowhere to be found.
A frantic search ensued, finally determining that the stem was inadvertently thrown into the trash can. The cement hardened in place before a replacement could be located. It seemed a disaster.
"Who put this in the trash!" Roared the surgeon. Silence followed. Until finally, one of the Japanese students exclaimed from the other side of the room, "Here it is. I have it on video!" It would have been better if he had not, because the tape revealed the surgeon mistakenly dropping the implant into the garbage.
For the next four hours or so, the hard cement was extracted and the procedure was completed. Not a single word was spoken.
The greatest improvement since that time is that the materials used in the implants are what are known as biocompatible. Usually made of titanium, these implants are secured with either screws or are "pressed fit" into the bone. Later, bone grows in and around the implants, securing them without cement.
Furthermore, the implants are now part of what are known as modular systems. This means that the socket, the ball and the stem are all separate and of various sizes, thus can be mixed and matched to a custom fit for each individual patient. The flexibility of these systems lies in the fact that they are not secured with cement, so if positioning is not perfect at first, it can be easily corrected. Eliminating cement also reduces infections and implant loosening.
Our complication rates have been extremely low with these newer systems, and they are much more easily managed when they do occur. Of the surgical options for hip dysplasia, and degenerative hip arthritis, total hip replacements are the least painful, provide the best biomechanical function, nearing 100 percent of normal, and the most rapid recovery.
Once healed, they should last for the life of the dog, providing a lifetime of pain-free function. I would say, with the improvements in this procedure, it is definitely worth a second look, should the need arise.
Dr. Henri Bianucci and Dr. Perry Jameson are with Veterinary Specialty Care LLC. Send questions to firstname.lastname@example.org.