FAQs on CCL: Cranial Cruciate Ligament Injuries in Dogs

a dog jumps in the  air at a park
Although a traumatic injury can cause a CCL rupture in dogs, rupture is thought to be the result of degeneration of the ligament over time, is most likely to occur through normal activity.

I frequently speak with pet owners whose dog has a suspected CCL injury. Here are the most common questions these owners have.

What is a CCL (cranial cruciate ligament)?

The cranial cruciate ligament is a ligament inside the knee of dogs that provides stability of the knee when a dog runs and walks. This ligament is very similar to the anterior cruciate ligament (known as the ACL) in people. These ligaments in dogs and people have nearly identical anatomy but different names because dogs walk on four limbs and people on two. CCL ligaments are only found in dogs’ back legs.

How is an injury to this ligament diagnosed?

In most cases, dogs present to the veterinary clinic with a back leg lameness or limp. Veterinarians will examine the dog, trying to isolate the source of pain. Veterinarians use two techniques to test the stability of the knee: cranial tibial thrust and cranial drawer. If there is thrust and/or drawer present in a dog’s knee, this indicates there is a CCL injury. X-rays are often recommended to help rule out any other causes of pain or lameness, but the ligament itself cannot be seen on x-rays. There are some x-ray findings that make veterinarians suspicious of underlying CCL injury, but true diagnosis is made from physical exam and laxity in the knee joint.

How did this rupture happen?

In dogs, cranial cruciate ligament injury and/or rupture is thought to be due to degeneration of the ligament over time. Unlike people, where a traumatic injury – often sports-related – causes ACL injuries, in dogs the cause is usually degeneration, which leads to injury or even rupture through normal activity. Although a traumatic injury can cause a CCL rupture in dogs, it is less common.

What can we do to help our dog feel better?

When a dog experiences a CCL injury, anti-inflammatory pain medications and rest are recommended. Human pain medications are not safe for dogs, so be sure to consult your veterinarian to discuss appropriate medications for your dog. In addition to rest and medications, surgery is the gold standard for treatment of a CCL injury. Various surgical techniques are available, and your veterinarian will discuss the best option for your dog.

How much does surgery cost?

I recommend that owners see a board-certified surgeon for their pet’s orthopedic surgery. These veterinarians have had additional training to specialize in advanced surgical techniques. As previously mentioned, there are multiple different surgical stabilization techniques for CCL injuries. The most-performed technique in the Chicago area is the Tibial Plateau Leveling Osteotomy (TPLO). These procedures cost between $4,000 to $6,000 in Chicagoland.

Can we use a brace like in humans?

Unfortunately, braces and/or wraps are typically not beneficial in dogs. This is because dogs walk on their tiptoes, so their knee is always bent. (Try it: If you stand on your tiptoes, your knee will be bent too). We humans walk flat-footed, so our weight can transfer from our hip to heel. Since this weight transfer cannot occur in dogs, braces are ineffective.

What if surgery is not an option?

In many cases, surgery is not financially feasible, or it may not be in the best interest of the dog due to other underlying health issues. In these cases, I recommend multi-modal therapy. This includes strict rest for 4 to 8 weeks, long-term non-steroidal anti-inflammatories (NSAIDs), high-quality omega-3 supplements, and glucosamine/chondroitin supplements, along with weight loss. After the period of rest, physical therapy can be very beneficial as well.

With time, the knee will stabilize, but with the stabilization comes more arthritis formation. The body develops arthritis to try to stabilize the knee joint. Surgery on the knee reduces instability, so the body does not form as much arthritis in that joint. However, even with arthritis, dogs are able to compensate well. Many dogs do well without surgery, although the injured leg may always cause some discomfort. The dogs that typically do not do well without surgery are very large dogs that already have joint disease, such as advanced hip dysplasia.

One exception to the surgery rule is toy breed dogs and cats. We do not commonly see CCL injuries in these pets, but when we do, they typically do really well with cage rest and medications and surgery is not often needed.

What about the other leg?

Unfortunately, over 50% of dogs will rupture their other CCL within a year of the first rupture. This can be explained by the fact that both ligaments are typically degenerating at a similar rate. I like to always warn owners of this because they may be faced with the decision to pursue surgery again soon.

How can we prevent a CCL injury?

Unfortunately, there seems to be a hereditary component. We do not have a good method of determining which dogs that will have CCL injuries in their life. However, maintaining an ideal weight is key to joint health. I would also recommend considering pet insurance prior to any issues. Insurance does not cover pre-existing conditions, so don’t wait until your pet starts limping. I have seen CCL injuries in dogs as young as 6 months old, but most commonly we see them in medium to large breed, active, overweight dogs aged 2 to 6 years old.

Dr. Drew Sullivan

COVID and Pets: An Update from the Frontline

dog lying on bed with box of tissues
We believe that transmission to pets is from contact with a positive human within the household. Transmission from pets to humans is considered extremely low. The occurrence of severe illness in pets is rare.

After two long years of this pandemic, we still do not know much about pets and SARS-CoV-2 (COVID-19), but over the last few months I have learned a lot. I am writing this blog as I am isolated in my basement with COVID-19. I am thankful for the protection I have received from vaccines as I am only experiencing very mild signs.

I hope to tell you what I have learned working firsthand with the first Illinois COVID positive dog over the past few months. According to the USDA there have only been 39 Polymerase chain reaction (PCR) positive dogs within the United States. The first dog in Illinois confirmed to be positive was a patient at Medical District Veterinary Clinic and was first tested in January 2022. He was positive on PCR, and viral sequencing information was obtained at the National Veterinary Services Laboratories in Ames, Iowa.

Since that time, I have had multiple other patients that are presumptive positives. A presumptive positive is when there is detection on a PCR test, but it is not confirmed positive with either virus sequencing or evidence of virus neutralizing antibodies. Obtaining sequencing data is challenging, most likely because the dogs have low viral load and very mild clinical signs.


We believe that transmission to pets is from contact with a positive human within the household. Transmission from pets to humans is considered extremely low. Due to the risk of transmission to pets, the CDC recommend avoiding close contact with pets if you are ill. The occurrence of severe illness in pets is rare, but transmission is possible. Pets presumed positive should remain isolated from other pets until clinical signs have resolved.

Clinical Signs

It is important to remember this is a human pandemic. We know that by comparing the large number of human cases of COVID 19 and the very few cases documented in pets.

I truly believe that most pets do not acquire the virus. If they do, they are typically asymptomatic or have very mild symptoms. The clinical signs I observed in these presumptive positive cases were upper respiratory signs: nasal congestion, sneezing, reverse sneezing, and gag-like cough. These signs were odd and did not fit with classic tracheobronchitis (canine cough). When I examined these dogs, they did not cough when I touched their neck to palpate their trachea, which is the typical response during a physical exam when the patient has classic canine cough.

We have seen patients with clinical signs suspected to be secondary to SARS-CoV-2 in the past 2 to 4 weeks.


Unfortunately, there is no approved or documented treatment for COVID in dogs or cats, but in most cases, they do not need treatment. For those pets with more severe clinical signs, I have found that corticosteroids seem to provide the most relief. The brachycephalic breeds seem to have more nasal congestion and difficulty breathing. In these pets, I have started anti-inflammatory doses of steroids and they seem to respond well.

In a few of these cases, chronic rhinitis (irritation/swelling of the mucous membrane in the nose) and sneezing has lasted for weeks to months. Home care for pets is similar to home care for most human COVID-19 cases. The virus needs to run its course. Be sure your pets continue to eat and drink. You can also put the pets in the bathroom with the shower running; the warm humid air can be soothing for the upper airway.


SARS-CoV-2 testing is not widely available for dogs or cats, but most large veterinary laboratories are offering PCR testing. Antibody testing is not widely available at present. If you feel you dog or cat has signs of SARS-CoV-2 after exposure to an infected person, I recommend contacting your veterinarian.

If you are a client at Medical District Veterinary Clinic, feel free to reach out to me and I may be able to assist in testing as I am collaborating with Dr. Ying Fang, a virologist, at the University of Illinois College of Veterinary Medicine.

– Dr. Drew Sullivan

Salty Paws Make Salty Dogs

Rock Salt Is the Real Culprit

There comes a point at the end of every year when you can no longer just grab the leash and causally head out for a walk with your dog. (That is, unless you have a Bernese mountain dog like my brother’s dog, Ruby, who would live in the snow if she could.)

Instead, you have to determine how many layers of clothing you and your dog need to go for a walk. I’ve been doing this dance for years with Emmie. Eventually she complies, thankfully. But, just once, I wish she would remember that when we don’t put the booties on and there is salt out, she ends up crying out and her paws hurt.

As cold as our Chicago winters are, there are really only a few days in any calendar year where it is so cold you have to truly worry about a dog’s paws. The real culprit that is causing dogs to lift up their paws and look at you like they’re auditioning for an ASPCA commercial is the rock salt. I’ve definitely had to carry Emmie a few hundred feet through a heavily salted sidewalk stretch when we were caught off guard.

So here are two ways to help protect your pet’s paws, plus what to do if you forget:


Yes, they are annoying to put on. Yes, they can sometimes fall off. And yes, most dogs don’t like putting them on. But booties are by far the best way to protect your dog’s paws, and when she’s outside she’s much happier.

The key is to find a brand that fits your dog well. Put in the extra effort to measure the size of your dog’s paws for best fit and look for waterproof options, if they are in your budget.

I’m a fan of Muttluks. They have a measuring guide to help ensure the best fit. Remember: Never use a rubber band or any other band that can be constricting to hold up the booties.


These can be used to try to prevent ice balls from forming between the toes. Balms also help keep small amounts of salt from bothering their paws. The base ingredient for most of these balms is beeswax, but sometimes you can use coconut oil as well.

The most common brand I see is called Musher’s Secret, though a lot of other brands are out there. The upside is that most of these can be licked or ingested with no concerns. The downside is that they tend not to work as well as booties.


If you are like me, sometimes you forget. (Or, TBH, are too lazy and depressed about how dark it is at 6:30 in the morning. Even after we go back to standard time, ugh! Which if any of you have a toddler like me, does not mean an extra hour of sleep!)

When you forget and your dog gets salt on her paws, rinse them off with cool water once you’re home. A warm water Epsom salt soak for 5 to 10 minutes will usually fix the problem if her paws are still irritated after everyone has warmed up from the outing. If the paws are still irritated or seem painful after a soak, give us a call.

What Food Is Best for Your Dog or Cat?

This is a question and a discussion that I have with clients daily. And to be honest, it’s a very difficult question to answer. I am going to give you a few tips on how to pick out a food that is best suited for your dog or cat.

From the American Association of Feline Practitioners: https://catvets.com/guidelines/practice-guidelines/life-stage-guidelines

Life Stages

I recommend feeding a food based on the life stage of your pet. The four life stages include growth, young adult, mature adult and senior. The below picture helps illustrate the life stages of cats. Canine life stages are pretty similar, but with more variation due to the vast size difference we see in the canine species. The growth life stage is typically done by 6-12 months of age. For cats the growth phase is typically finished by 6-10 months of age and I recommend transitioning to adult food around that time. If you have a puppy or kitten it is very important for proper growth and development to feed a puppy or kitten food. In the same manner as your pet is aging feeding a senior diet is important as they have different nutrient profiles.

You may ask what about an “All Life Stages” dog or cat food. For a company to market their food as “All Life Stages” the food must meet the nutritional requirements for all life stages. Therefore, most of these foods are formulated as a puppy/kitten food because puppies and kittens have the highest nutritional requirements of the four life stages. These foods can be good foods and well balanced, but they typically have a high caloric density. Therefore, in my experience, dogs are more likely to become overweight than if they were fed some other diets.

Medical Conditions

Does your pet have any health conditions that require a special diet? Prescription diets can play a vital role in management of many health conditions, including kidney disease, diabetes, obesity, allergies, and feline lower urinary tract disease.

If your pet suffers from a medical condition, diet can manage and help many conditions, so I always recommend considering a prescription diet if you pet has one of the above conditions.

More Expensive Does Not Mean Better

Many pet food companies are great at marketing but might not be as good at formulating diets. You can always look for the Nutritional Advocacy AFFCO (Association of American Feed Control Officials) Statement on each bag or can of food. These statements will tell you if the food has been through a food trial or formulated to meet particular feeding guidelines. The ingredient list should also list all ingredients in decreasing amounts by weight.

Labels are very confusing and often misleading to consumers. For example, if I made up a food with the following labels, the variation in ingredients can be drastic.

  • If the term “All” is used, then the ingredient must make up 100% of product minus preservatives and water. So, this treat would be 100% beef
  • If the listed ingredient is used, then the ingredient must make up 95% of product minus water. So, this Beef Dog Chow would be 95% beef on a dry matter basis.
  • If the term “dinner,” “platter,” or “recipe” is used, then the ingredient must make up only 25% of product. So, this Beef Dinner is likely only 25% beef.
  • If the term “with” is used, then the ingredient must make up only 5% of product. So, this Dog Chow with Beef is likely only 5% beef.

I hope this illustration helps demonstrate how confusing pet food labels can be to both consumers and veterinarians. I recommend visiting the AAFCO website if you want to be better educated about what’s in your pet’s food.

Say No to ‘Grain Free’

Does my pet need grain-free food? The answer is NO. There little to no research showing the true benefit of grain-free food. In fact, grain-free food has been shown to cause heart disease in some dogs. The exact cause is still being researched. Visit this site for more information. https://www.fda.gov/animal-veterinary/animal-health-literacy/questions-answers-fdas-work-potential-causes-non-hereditary-dcm-dogs

What About Raw Food?

Some dogs do really well on raw food, but I do not recommend it. That’s because I see too many owners who try to feed raw but who are not feeding a balanced diet because they are solely feeding raw meat and limited other nutrients.

In the wild canines and felines will consume entire animals. Eating meat, skin, ingesta, organs, and bone makes up a balanced diet.

Raw can be balanced and can be a good diet for some animals, but there is also a public health risk with feeding these diets. This is a statement from the CDC:

“Germs like Salmonella and Listeria bacteria have been found in raw pet food, even packaged ones in stores. These germs can make your pet sick. Your family can also get sick by handling the food or by taking care of your pet.”

Centers for Disease Control and Prevention

Therefore, if there are young children or anyone who is immune-compromised in your house, I highly advise against feed raw pet foods.

Each Pet Is Different

I hope this information has been helpful and informative. I recommend discussing your pet’s daily calorie needs with your veterinarian as each pet is different, just like people. Two people that have ideal weights of 180 pounds may be able to eat very different diets to maintain their weight, and the same goes for cats and dogs. All 10-pound cats do not need the same daily calories.

The recommendations on the bag or can of food should only be a guide. Some animals may need more calories, but most will need less than the recommended amount to maintain an ideal weight. And always remember to factor in all treats and table scraps into their daily calories. Most pets are overweight these days.

—Dr. Drew Sullivan

Fear Free Practices for Furry Friends

For many people, the doctor’s office can be a scary place. So it is no surprise that many pets view going to the vet with a similar fear.

Our clinic truly believes in Fear Free practices. Our goal is to limit your pet’s stress and fear and make visits with us as pleasant as possible. There are various ways that we do this, which I would like to share with you.

Treats, Teats, and More Treats!

During your pet’s visit you will notice that we like to offer treats. We have biscuits, cheese, peanut butter – like a candy store for dogs and cats! This is not only because we think your pet is adorable and we want to spoil them, but this is also a main way we like to bond with them.

Imagine if you are at the doctor and you are anxiously waiting, and then the doctor walks in and immediately offers you your favorite treat (for me, that would be some delicious baked goods) and socializes with you. You would likely feel much calmer and connected to them. This is the equivalent of what we do with your pets.

Although we have lots of treats, if you have a dog or cat that is pickier with food, please feel free to bring whatever your pet likes best. This is not uncommon, as I have seen many patients that would eat only one food.

We encourage owners to offer treats as well during visits to help make the entire experience as positive as possible. We joke that visits go best when our patients come hungry, so you may want to consider bringing your pet to see us with an empty stomach so there is plenty of space for treats!

Getting on Their Level

We want our patients to feel comfortable, so we often will sit on the ground with them. We hope that by sitting on their level they feel less intimidated and fearful, and that they see us as their “friend.” I have noticed that when I sit on the ground and spend time in the room before even beginning my exam, my patients generally seem more at ease.

Please do not feel obligated to sit with us, but if you would like to you are totally welcome!

Limit Stress from Other Pets

Many cats never leave the home except to go to the vet. They may be stressed by traveling before they even arrive.

The smells and sounds of dogs can be very scary for them, too, which is why we recently created a separate feline waiting room and exam rooms. We use all separate supplies, have tasty treats and fun toys, and have nice feline-friendly smells. In the months since we have started using this new space, I have noticed that cats overall seem much calmer and happier. 

Dogs can be become upset from other pets as well. Some of the sweetest and most affectionate dogs that I have met do not get along well with other dogs. Being around other dogs is stressful for them. I personally have a dog-reactive dog, and while she loves people, other dogs make her highly anxious.

To reduce this anxiety, we have multiple tactics, such as choosing specific exam rooms and trying to limit time in the clinic and exam room, when other pets are a trigger for the patient. We also perform exams outside in an isolated area if needed.

Fear Free for Your Pet

Please let us know if your pet is reactive with other pets, or there are any other behavioral concerns, and we will work with you to formulate a plan for their visits.

I hope you can see how much we at Medical District Veterinary Clinic truly care about our amazing patients! We look forward to continuing to make their time with us as fun and enjoyable and fear free as possible!

Amber Slaughter, DVM

Tips for Parenting a Puppy

[Dr. Sullivan's puppy, Winnie]
Meet Winnie.

Life as a new pet parent can be challenging, and to be honest, you never really know what to expect. After losing Oskee, our dog of 14 years, last fall, I knew our family would get a new dog, but we just didn’t know when. We were not in any rush, but over the past few months, we were discussing it more and more.

This past month we adopted a puppy from a rescue in Central Illinois called Hudson’s Halfway Home. I had the privilege of working with this rescue group before moving to Chicago, and they do amazing work. Our family was lucky enough to adopt a 6-month-old puppy, and she has been a great addition to our family.

Even though I see puppies daily, it had been more than 15 years since I had a puppy at home, so I had a lot to think about before bringing Winnie into our family. Here is my list of ways you can help set a puppy up for success.


Most important is creating consistency among all family members to avoid confusion for new puppies. Having a routine that everyone follows around housetraining, feeding, basic commands, and so on will help your new dog catch on quickly.


When it comes to housetraining, it is very important to be proactive early on. Puppies initially will not ask to go outside to go to the bathroom. Anticipating when they may need to go and then providing a small reward once they go outside is key. Additionally, do not confuse puppies by trying to teach them both potty pads and grass early on. I always tell owners if your goal is to train to go to the bathroom outside, that should be started from Day 1. After they are puppy pad trained, they can still be trained to go outside, but it may be more challenging.

Consistent diet

Puppies commonly have intestinal parasites and are also known for eating/chewing on everything. Keeping puppies on a consistent diet will help keep their bowel movements regular and predictable. Feeding an overabundance of treats and/or human table scraps will likely lead to soft stool/diarrhea. When puppies have diarrhea, the frequency of defecation increases, so accidents inside are common, further delaying potty training. Not to mention that a poor diet could make puppies very sick. I always say avoid the human food. It is not a good habit to start at such a young age.

House safety

Be sure you puppy-proof your house and have limitations for your new puppy. I highly recommend crate training. Crates are not to be used as a source of punishment, but a place where puppies feel safe and secure. The training may take time, and you may need to sleep next to the crate initially, but once puppies realize it is their safe place, it is wonderful. Having a dog crate trained also keeps dogs safe when you are away. If crate training is not for you and your puppy, then using baby gates to create boundaries can be used similarly. In addition to boundaries, make sure all garbage cans have lids or are in cabinets. Be sure electrical cords are placed where puppies can’t chew them. Keep all cleaning products away from the puppy. Puppies love socks, so use caution to prevent your puppy from eating your socks.

Preventive care

It is very important to take your new puppy to the vet as soon as possible for an overall health check and vaccines, if needed. Typically, puppies receive vaccines at 8, 12, and 16 weeks of age. Additionally, puppies should have an intestinal parasite screen for worms (very common in puppies) and need to be started on heartworm, flea, and tick prevention as young as 6 to 8 weeks of age.


It is very important to socialize puppies with both dogs and people. Puppies mature so quickly that it is important to start socialization very early on.


If you are considering insurance, the best time to purchase is when you have a puppy with, hopefully, no pre-existing problems. Once a problem occurs, most companies will consider it pre-existing and insurance will not cover treatment of that problem the remainder of that pet’s life (allergies and ear infections, for example). There are many insurance companies, so to find one that’s right for you consider whether you are looking for coverage for accidents and illness or full coverage that includes wellness/preventive care.

Over the past three weeks, our family has made changes to our routines to accommodate Winnie. She is adjusting well and, luckily, our house is somewhat puppy-proof because it is somewhat kid-proof (minus all the kids’ toys).

We are crate training her, and she is doing great. She loves her crate and goes in willingly at bedtime. During the day, she prefers never to go in, but when we leave the house, she does great in her crate. When we are home, she goes outside to pee every few hours, and she can make it through the night without an accident. So overall, housetraining is going very well, though there have been a few accidents.

We are both trying to figure each other out. Since she had lived in a kennel setting for 4 months, the grass and leash walking were brand new to her. Now that she is catching on and is gaining confidence outside, she is doing well. She still does not alert us when she needs to go out, so we try to stay proactive in telling her it’s time to go “potty.” With a continued consistent routine, I’m confident we will be accident-free in a short time.

Like many of you, we are thrilled to have a new dog in our home. We love having Winnie in our family. Start early and stay consistent to set your puppy or new dog up for success.

Dr. Drew Sullivan, Medical Director

The ‘Why’ Behind Common Dog Vaccines

You bring your dog to the vet every year for a physical examination and vaccinations. But do you recall why your dog is receiving her shots and how her doctor has decided which ones she needs? The following is a summary of the vaccinations we offer and the diseases they prevent.


Rabies is a virus that is contracted through the saliva (usually a bite) from an infected animal. Because rabies is always fatal and can be transmitted to humans, it is required by law that pet dogs be vaccinated. The first rabies vaccine your pet receives can be given as young as 12 weeks of age and must be re-administered one year later. Subsequent vaccines are given at either one- or three-year intervals.

DAPP, aka Distemper

This combination vaccine protects your dog from four respiratory, neurologic, and gastrointestinal viruses (distemper, adenovirus, parvovirus, and parainfluenza) that are in the environment and easy to contract through contact with an affected dog or contaminated feces. It is especially important that puppies receive this inoculation at appropriate intervals. The immune system of puppies is immature and not ready to battle these diseases. We administer this vaccine starting at 6 to 8 weeks of age, and continue every 2 to 4 weeks until your dog is at least 16 weeks of age. As your dog gets older, this vaccine will be given less frequently since his immune system is armed with antibodies to fight illness.


A bacteria found in standing water, leptospirosis is transmitted through the urine of infected rodents. A dog can contract the bacteria by drinking out of, or even walking through, a contaminated puddle. Symptoms range from mild gastrointestinal signs to liver and/or kidney failure. This potentially fatal disease is communicable to humans, so we strongly recommend all dogs receive the vaccine once a year.

There are several vaccines we give to dogs based on their lifestyles, which determines their risks.


Bordetella is the bacteria implicated in “kennel cough,” a respiratory illness that is easy to transmit through contact with an infected dog or through nasal or oral secretions. If your dog has contact with dogs you don’t know at a park or kennel, she should receive this vaccine. Puppies can get this vaccine as young as 6 weeks of age. It requires annual boosters.


The Lyme disease vaccine protects dogs against the spirochete Borrelia burgdorferi, which is transmitted by ticks. Lyme disease is characterized by arthritis, lameness, fever, and rarely, a serious kidney disease. If your dog spends any time in the woods and has exposure to ticks, this vaccine is recommended. It’s worth noting that protection against ticks is an essential part of disease prevention, since Lyme is not the only disease ticks can transmit.

Canine Influenza virus

Canine flu causes fever, cough, and fatigue and can lead to life-threatening pneumonia. It’s transmitted through oral or nasal secretions or through contact with a contaminated surface. If your dog spends time around dogs you don’t know at a park or a kennel, this vaccine is an important part of disease prevention.

Vaccinations can protect your dog from contagious diseases, some of which are fatal. As your pet’s caregiver, you should understand the preventable diseases your dog is at risk for contracting. Please call our office if you have any questions about these vaccines.

Barrie Yallof, DVM

Image by Rajesh Balouria from Pixabay