Carpal Laxity Syndrome is a more general term, used for both hyperextension and hyperflexion deformity - the cause is not known (no matter what someone on the internet says) but may be related to unbalanced growth, poor muscle tone (as expected in babies), or weakness between the flexor and extensor muscle groups. In some puppies who didn't have a great start and come into rescue underweight seem to be affected when they start on higher-quality diets. Sometimes it seems to be related to well-meaning foster carers pushing too many calories into the puppies to get them to a normal weight and this pushes their growth too fast. In other cases, the puppies were already on their way to the condition and the change in diet triggered it. Flooring is important, we need to get them off slippery surfaces which might include tiles, floorboards, and newspaper, they need something for their toes to grip. Genetics have also been implicated because certain breeds such as Shar pei's and Dobermann's seem to be more affected. The good news is that most dogs come through this unscathed in their own time (typically in 1-2 months) as long as they're on a balanced diet, suitable flooring and not crate rested.
Male puppies seem to be more affected due to their more rapid growth and that has been our direct experience with foster puppies.
The age of presentation is usually 6 to 16 weeks; dogs may be unilaterally or bilaterally affected. While all breeds can be affected, large breeds tend to be affected more often than small breeds - fat puppies also are going to be a trigger, we want the babies to be a healthy lean weight, not fat which can be seen in affected bull breeds such as XL & pocket Bullies who are very prone to this condition.
The degree of bending can be very minor or very pronounced, the more pronounced, generally, the longer it is going to take to rectify and may need other supportive measures. The photo directly below of the merle and white puppy is a Great Dane, they grow very fast and can be prone to knuckling no matter how great the breeder is.
The first red flag is often the twisting of toes - this is the ligament laxity beginning and whilst some puppies will not advance past this stage, this is your opportunity to do some tweaking. Toe twisting can be seen around 3 weeks when puppies are being introduced to weaning foods but may occur later as well.
Balanced diets are very important for these puppies, whether that be a puppy kibble or a balanced commercially available fresh food diet.. Puppies on the cheapest and also the most expensive foods can knuckle, unfortunately, we don't have a great understanding of the whys and hows of this condition yet. It is important you see your Vet so they can monitor your puppy, it is unlikely your Vet will recommend anything too different from what we are but your Vet is an important partner in your dog's recovery. Your Vet also may not know how to go forward with this as they may not be experienced, so you can list the things we recommend and make sure they're ok with it. There are also some very dramatic people on the internet who don't actually know much about this condition and demand you get a referral to an Ortho specialist or Physiotherapist...we can keep calm in the initial stages and for most, this will be complete overkill, your Vet will know when it's time to refer you on.
Online advice will give you conflicting information, one of the most common pieces of advice is to slow down growth by reducing protein in their diet, this isn't a terrible idea but if you decide to go down this track, be sure the diet you're giving is still a balanced diet. The minimum protein for puppies is around 23% Dry Matter (DM), so do not go under this, it's not healthy and is terrible for muscle development - 24% in dry food would be fine and you'll find that in many large/giant puppy formulas and you can give to dogs of all breeds and sizes - contrary to popular belief, different breeds don't need special dry food.
While the condition is generally self-limiting, affected puppies should only ever be on surfaces they can grip, this means they should not be slippery surfaces such as floorboards, tiles, smooth decking, newspaper, etc. Taking an affected puppy on a walk is not appropriate nor is physical play with non-littermates. Puppies should be kept on surfaces such as carpets, rubber mats, pebbles/gravel & grass. Whilst penning/crating a puppy may seem appropriate when the puppy struggles to walk, it is generally recommended that the puppy still moves about on these appropriate surfaces – caretakers should take a common sense approach and follow the advice of their Vet.
Puppies who are knuckling over should be kept in warm environments as cold weather can worsen the condition.
Should splints be used in more severe cases?
There is no right, or wrong answer here - there are 2 studies looking at both options and both options were successful. Many Vets will ask for the dogs to be left without splints but restricted to a safe area (not a crate or pen) with appropriate flooring with the hope that within 2-4 weeks the condition will rectify.
Whereas other Vets will want to splint for anywhere between 7-10 days to get on top of the condition quickly. Long-term use of splints is not appropriate unless absolutely necessary as it will lead to muscle atrophy.
Splints can sometimes be tricky to keep on and some dogs may object and bite at the bandages keeping the splints in place. The puppy may also start to knuckle again after the splints come off.
Dogs with secondary carpal contractures (the inability to extend the carpal {wrist} joint) that are not wearing splints require stretching sessions two to three times daily. The families Vet can show them how to do this or a referral to an Animal Physiotherapist can be given.
Adopting/selling puppies with the condition
Ideally, puppies should stay with their foster carers/breeders until fully recovered, however, it would be deemed appropriate for puppies to start their journey with their new families and start socialisation if the knuckling over is minor/on the mend and the family understands what to look for and how to manage the puppy.
In an exceedingly small amount of serious cases, the dog may need minor surgery to correct the contractures and this should also be discussed with new families so they know what they're getting into.
New families should ensure they are not overfeeding their puppy, growing their puppy in a lean state is the goal. Choosing a high-quality diet is imperative. For families wanting to stay with a dry food diet, I would recommend an Australian brand called Stay Loyal and select their Large Breed puppy formula even if the dog is small as it has appropriate protein fat, calc & phos amounts to encourage slow growth. We recommend you try and keep to below 26% protein. For families who want to feed a fresh food diet, I recommend Prime100 / Big Dog Puppy OR Vets All Natural Complete Mix Puppy that you add fresh meat to and offer edible raw meaty bones around 4 times per week such as chicken necks, chicken frames, chicken wings etc. – whatever is an appropriate size and style for your dog. Supervise your dog when they are eating bones. Learn more about bones here.
Supplements We recommend the following supplements for these puppies, starting off with the most important so if you can only do one, start there. It's important to start supplementation at the first sign of knuckling.
Sure Grow 100
This is our go-to, Australians, Amazon is typically the only place you'll find this American product, grab yourself 2 bottles so when one runs out, you order the next so you're not without. Double dosing this for 1-2 weeks with your Vets ok is the general recommendation and then keep on a maintenance dose until you are at least a couple months passed rectification. If you cannot get Sure Grow, grab yourself some Virbac Calci-D, you can double dose this for 1-2 weeks with your Vet's ok and then keep on the normal labeled dose. For non-Australians, find yourself a dog Calcium supplement, you can find them online or at your Vet - the recommendations are the same as the above.
MSM Powder Supports connective tissues such as collagen, ligaments, and tendons. We make My Doggie Support which is the highest quality MSM available paired with vitamin C for further bioavailability. If you are not in Australia, below is the dosage for MSM, try and find OptiMSM being the most pure version. 1-10 kilos of body weight: 1/4 teaspoon 10 - 20 kilos of body weight: 1/2 teaspoon 20 – 40 kilos of body weight: 3/4 teaspoon over 40 kilos: 1 teaspoon and then 1/4 teaspoon for every 10 kilos over that These doses can be doubled when there are joint disease/challenges. When not giving My Doggie Support, add Vitamin C to increase the absorption of MSM. Use a ratio of 4 parts MSM to 1-part Vitamin C. Ester C is much gentler on the tummy than standard Vitamin C and comes in a powder.
Vitamin C Look for Ester C as it's more gentle on the tummy. Your Vet will be able to confirm the dosage, generally 250mg for a large breed puppy is enough, you can read more about vitamin C and dosage here.
Zinc PAW by Blackmores Coat, Skin + Nails Multivitamin Chews
Glucosamine and Chondroitin PAW by Blackmores Osteo Advanced
Anitone
A liquid, organic, nutritional supplement providing over 60 minerals and trace elements in a highly bioavailable, chelated form. Google for the best price. Dosage as per packaging. Link to product here.
Antinol Plus
An incredibly powerful full spectrum omega-3 supplement that not only is used in dogs with active joint disease but also used to support the growth of puppies and acts as a preventative of joint disease. Some nice side effects include improving trainability in puppies but also improves coat and skin.
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References:
https://www.thieme-connect.com/products/ejournals/pdf/10.1160/VCOT-06-06-0051.pdf
https://www.vin.com/apputil/content/defaultadv1.aspx?pId=11343&catId=34572&id=5124419
http://vethq.com.au/doby-carpal-laxity-syndrome/