Last Updated on February 19, 2022 by Allison Price
One of my email friends mentioned that her horse had a “popped knee” while I was talking to her. Although I didn’t want to appear ignorant, I don’t know what it means. Do you have any ideas?
Popped knees is a term that refers to enlargement of the front of the horse’s carpal joints. It looks like the knee has “popped out”. This can sometimes be accompanied by lameness or marked discomfort. The most common cause of an enlargement in the front of a knee is the enlargement or three synovial structures. These are the three tendons that run over the fronts of the knees (flexor, flexor, and extensor carspiradialis), the two joints and one bursa. An inflammation in any one of these structures can cause an enlargement of the front of your knee, giving the appearance of a “popped” knee.
There are many causes. Popped knees are most commonly caused by a chip in a joint in racehorses and horses that perform at high speeds. Other causes include infection, developmental abnormalities in foals, rupture of their tendons in front, and trauma to the knee.
It is important to determine which structures are affected as treatment options can vary. Sometimes, all three structures may be involved. Other times, only one structure might.
It is also crucial to receive a diagnosis as soon as possible. It’s actually the most important thing you could do to get treatment. A veterinarian will be able to diagnose your condition quickly and provide you with the best treatment possible.
Do-it-yourself remedies might be suggested by older horsemen, but this is a disservice to horses. The problem cannot be solved by simply applying anti-inflammatory medication or bandaging the knee. The horse owner who tries to fix the problem by treating the horse herself for two to three months using old-fashioned liniments or bandages for horses with chips in their joints, is likely to decrease the chances of the knee being repaired. If the injury is not treated, it can get worse and lead to severe arthritis.
A veterinarian will combine radiographs, ultrasound, and a physical examination to diagnose a popped knee. The physical exam involves the examination of all structures, observation and the results of flexion tests. Infection can cause fever, lameness and synovial fluid with excessive white cells. Ultrasound and X-rays can clearly identify the structures involved. It is also important to determine the response to local anesthetics that are placed in the joint.
The cause of the problem will determine the treatment. Bone chips can cause inflammation of the joints and tendon sheaths. Most bone chips can be removed arthroscopically. This type of surgery can often be completed in under anesthesia for horses within a matter of minutes. The horse can usually return to work within 60 to 90 days, unless there are any complications.
Direct trauma to the tendon sheath soft tissues can be treated by veterinarians with anti-inflammatory medication like Bute or banamine. The vet will then ice the wound, bandage the leg or sweat it, and allow the horse to rest. This will often reduce the swelling in soft tissues, and can take several weeks to fully recover.
The horse should be drained and flushed with water. Horses that are very lame should be restrained during the recovery period. This can take anywhere from 3-4 weeks to 3-4 months.
A veterinarian will usually place the affected leg in half-cast for a few weeks if there are any developmental abnormalities. After the cast has been removed, the leg is covered with support bandages and the foal is kept in the stall for a few months. The results are usually good.
The cause of the problem will determine how prognosis is made. It all depends on where the bone chips are located. There are many classic places for bone chips in racehorses’ knees and each one has a different prognosis. Horses can be very successful after the bone chips are removed. After surgery to remove a bone chips, Spend a Buck won Kentucky Derby. The prognosis for those with severe slab fractures, such as those that have “popped”, is much lower.
Direct trauma is a case where the structure that was damaged determines how successful it can be treated. The prognosis varies from a limited recovery to a full recovery.
Popped knees from infection will have a different outlook depending on the severity of the infection, the time they’ve been present, and the source of the injury. The horse may make a full recovery or need to be put down.
The prognosis for foals with developmental abnormalities is favorable. After reaching maturity, some horses have no problems.
You can reduce the risk of your horse getting popped knees. You must first make sure that your horse isn’t being over-trained. Overtraining can cause hardening of the carpal bones which then makes the bones more susceptible to breaking (chip). Try to minimize situations that can traumatize your horse’s knees.
If your horse has popped knees, it is important to get treatment as soon as possible.
I’m Allison, born and raised in San Diego California, the earliest memory I have with horses was at my grandfather’s farm. I used to sit at the stable as a kid and hang out with my Papa while he was training the horses. When I was invited to watch a horse riding competition, I got so fascinated with riding!