Flat Chest & Concave Chest in Newborn Puppies: Treatment, Info & Common Misconceptions
- Sabrina Martin
- Aug 18, 2022
- 5 min read
Updated: Feb 5
Chest deformities are a common occurrence in many mammals, including puppies. The most common types are flat chest and concave chest. These are the most prevalent and discussed by breeders as the conditions have taken many puppies' lives unexpectedly. We, at FrenchiExotics, are beyond happy and proud to have introduced a proper solution that has saved many puppies in the past 4 years - The Flat Chest Kit - discussed in more detail towards the end of this blog post. But first, let's review each chest deformity and the risks they pose to newborn puppies.

Flat Chest
Flat Chest is a condition in which a puppy is born with or develops a flat chest due to congenital and/or environmental factors. This could be caused by a number of things, such as but not limited to:
laying on a flat surface
overeating
Swimmer's Syndrome
The condition is typically noticed in puppies that are newborn to 5 weeks old, with the majority of the cases occurring between 7-14 days old.
One of the most common causes of flat chest is laying on a flat surface. Specifically, a hard surface with no traction or bumps. This type of surface encourages puppies to lay flat on their bellies 24/7. It's recommended to have puppies lay on egg crate foam or rolled up towels instead. The flat surface starts becoming a big problem when the puppies are at the stage where they are quickly gaining weight and consequently applying excessive pressure on their chests. This and overeating are the most common causes of a flat chest in a newborn puppy.
As mentioned, there is such a thing as overfeeding a puppy. It's vital for them to gain weight daily, but overdoing it may do more harm than good. The extra weight of their big bellies creates too much pressure for their chests to handle, resulting in a flat chest. We very often see that puppies with a flat chest are being fed every 2 hours, as much as they will eat, for weeks. This creates puppies that are highly susceptible to developing this condition.
Thirdly, one of the biggest misconceptions with respect to chest deformities is that "flat chest" and "Swimmer's Syndrome" are synonymous. This information, which is widely flooding the internet, is extremely dangerous and potentially fatal to a puppy at the hands of a worried whelper browsing through Google for help. We were in those shoes, ourselves, at one point. The top search results for "flat chested puppy" all suggested tying our 10 day old puppy's legs together. We did this and almost lost our puppy 2 days later when the condition worsened.
Swimmer's syndrome typically occurs when a puppy is 3 weeks and older, when they are trying to walk but cannot seem to get their legs underneath them. If the muscles in their hind legs lack strength, you may notice a puppy dragging itself on its chest. Overtime, this applies excessive pressure on the chest bones, which may result in a "flat chest". At this point it would be advisable to tie the puppies hind legs to fix the swimmer legs & place a Flat Chest Kit cast on the puppy to fix the deformed chest (if applicable). Please note that it is normal for newborn puppies to drag themselves prior to 3-4 weeks of age! You should not be tying their legs at that point. Flat chest that occurs prior to this time is most likely caused by one of the other factors listed above. Remember: Swimmer's Syndrome can cause a flat chest, but flat chest is usually not caused by Swimmer's Syndrome.
Concave Chest
Concave chest, more commonly known as "Pectus Excavatum", and flat chest are very similar. With this condition, the chest dips inward. The puppy will exhibit very similar symptoms to a regular flat chest but tend to be more aggressive, as a concave chest is exerting a lot more pressure on the puppy's vital organs. This type of deformity is typically congenital and may be attributed to genetics.


Symptoms
Here are some symptoms to look out for in a flat chested puppy:
lethargy
not nursing/eating
difficulty breathing
increased aspirations or regurgitations
A chest that is compromised enough makes it extremely uncomfortable for puppies to perform essential activities for the continuity of their own life. The little nourishment they get in their bellies becomes more likely to be aspirated or regurgitated. This all leads up to the puppy's death if not addressed on time.
Always consult your veterinarian as a flat chested puppy is susceptible to developing conditions due to its flat chest, such as aspiration pneumonia.
Diagnosis
It's usually relatively simple to diagnose a puppy with a chest deformity by carrying it and feeling its chest. You can check for the following:
flat center of chest with sharp bends at the ribs, creating a sharp angle
chest dips inward when the puppy breathes
compare to littermates' chests for abnormalities
If you are unsure, you can always get the puppy checked out by a vet for a proper diagnosis. We are also available to help with the diagnosis.
The Solution
Yes, there is a simple and noninvasive solution to treating these chest deformities! The Flat Chest Kit is an invention that was created when we faced the same issue thousands of breeders face with their litters every single day. The kit comes with 6-9 different sizes depending on which kit is purchased. Our original kit (sizes 0-5) was created for smaller breeds, while our expanded kit (sizes 0-8) was created keeping all canine breeds in mind. It's always recommended to use our sizing chart prior to purchasing a kit and keep in mind that this is a treatment, so your puppy may need to grow into multiple sizes for a full recovery.


The Flat Chest Kit works by taking pressure away from the center of the chest and forms your puppy's chest to its optimal shape. This alleviates some of the symptoms that come with an untreated chest deformity. The casts should never squeeze the puppy. If a size is too small & the next size up is too big, always use the bigger size. You can make up for the extra space with some padding. You can watch our tutorial on how to properly place a cast on your puppy here!
Ultimately, our goal is to spread the word about these conditions and how they are, in fact, treatable. We especially want to target veterinarians, as they often recommend euthanizing puppies that have a flat chest. Every puppy should be given the opportunity to live and fight for its life. Putting down a puppy with flat chest is absolutely absurd & infuriating considering there is a cure and it does not require surgical intervention. If you are dealing with this, I hope we can help you save your puppy. If you have never dealt with this, I highly recommend having a kit on hand as chest deformities can develop at any time and progress very quickly.
Please feel free to reach out anytime should you have any questions about our product. Thank you for the trust!
Supporting Equipment & Tools
If your puppy is suffering from a flat chest, it is crucial to place your puppy in one of our casts first and foremost. It's also recommended to have the following equipment & tools on hand:
tube feeding kit (be sure to use the correct size FR)
feeding bottle
syringes with Miracle Nipple
incubator for isolation
My list of recommended products goes on and on, but these are just a few of the top items we suggest having on hand to properly treat a puppy with a flat chest. You can also check out our Amazon storefront for other products that we deem to be essential!
used it for 4 weeks. went to the biggest one size 5. noticeable difference within days. he was walking and playing with others while wearing it. it was a wonderful result!
Just received the kit. How long should you leave the brace on. 24/7 I assume but how long does the process typically take? Day? Weeks? Months?
Hello. I received the expanded flat chest kit in the mail today, I knew it probably wouldn't fit our little guy for long but am desperate to find a solution. He is now 5 weeks old and the largest brace, in the expanded kit, sadly is too tight once I put the padding in. I do not plan on returning it as I now know how crucial early treatment is and never want to put a puppy or myself thru such a heartbreaking ordeal. We started multiple types of physiotherapy about a week and a half ago. Including: taping / hobbling, built a stabilizing shoot for him to walk in, massage, put him in a sling, changed bedding/ flooring …