It trots along normally, then lifts a back leg for three or four steps before carrying on as if nothing happened. Many Pomeranian owners know this little "skip". It has a name: luxating patella.
This article is for information only. Only a vet can confirm a luxation and assess how severe it is.
What is a luxating patella?
The kneecap (patella) is a small bone that slides in a groove at the front of the knee. In some dogs, this groove is too shallow, or the leg bones are slightly misaligned. The kneecap can then slip out of place, usually towards the inside of the leg: this is called medial luxation.
In small breeds, the condition is most often congenital: the puppy is born with a joint that makes luxation more likely. A knock or a jump can trigger episodes, but they're generally not the root cause.
A breed that's particularly affected
Luxating patella is one of the most common orthopaedic problems in Pomeranians. The Orthopedic Foundation for Animals (OFA), a US screening body, ranks the breed among the twenty most affected. A veterinary study was even devoted specifically to the surgical treatment of this condition in Poms.
Signs to watch for
- The "skip" of a back leg: the dog lifts the leg for a few steps, then puts it down and carries on normally. It's the most typical sign.
- A back leg it stretches backwards, as if to put something back in place.
- Lameness that comes and goes, more noticeable after exercise.
- In advanced cases: bow-legged walking, difficulty jumping, permanent lameness.
Many dogs don't seem to be in pain during episodes. But a kneecap that slips out regularly wears the knee cartilage, and arthritis sets in over time.
The four grades
The vet assesses severity by handling the knee. Four grades are usually described:
| Grade | What happens |
|---|---|
| 1 | The kneecap only slips out when pushed, and goes back in on its own. |
| 2 | It sometimes slips out by itself during certain movements, and can stay out for a while. |
| 3 | It's out of place most of the time, but can be put back by hand. |
| 4 | It's permanently out of place and can't be put back. The dog limps clearly. |
The grade can change with age. Regular check-ups let you follow its progress.
Treatment
For grade 1, and some mild grade 2 cases, the usual approach is to monitor and adapt daily life. For grades 3 and 4, and grade 2 cases that bother the dog, surgery is generally offered: it deepens the groove the kneecap slides in and, if needed, realigns the tendon attachment.
In Pomeranians, a study of 55 operated dogs showed excellent results for grade 2, and a higher risk of recurrence for grades 3 and 4. It's an argument for not letting a luxation progress without advice.
Day to day: protecting its knees
Whether or not it has a luxation, these habits are kind to a small dog's knees.
1. Limit jumping
A sofa or a bed is four to five times a Pom's height. Every time it jumps down, its knees take its whole weight. A small set of stairs or a ramp at the foot of the sofa and bed turns that jump into a few steps. It's one of the simplest and most useful changes for a small dog.
2. A healthy weight
Every extra gram puts weight on the joints. Your vet can tell you your dog's ideal weight.
3. Non-slip floors
Tiles and polished wooden floors make little paws slip. A few rugs along its usual routes help it keep its footing. Also trim the hair sticking out between the pads.
4. Well-maintained muscles
Regular walks, at its own pace, maintain the muscles that stabilise the knee. Avoid ball games with sudden stops and sharp turns.
5. Carry it properly
Always support its hindquarters when you carry it, rather than lifting it under the front legs.
Frequently asked questions
My Pom skips a leg now and then, but seems fine. Should I see a vet?
Yes. Even if the dog doesn't seem to be in pain, an exam tells you the grade and lets you follow its progress. Better to know early.
Can I put the kneecap back myself?
It often goes back on its own. Don't handle your dog's knee unless your vet has shown you how.
Can a luxating patella affect both legs?
Yes, it's common in small breeds.
Should it avoid the stairs at home?
Climbing steps of a suitable height isn't a problem. It's mainly jumping down from a height, repeated every day, that strains the knees.
Sources: Wangdee et al., Evaluation of surgical treatment of medial patellar luxation in Pomeranian dogs, Vet Comp Orthop Traumatol, 2013; American Pomeranian Club, Luxating patella. This article is for information only and does not replace a vet's advice.