Patella Alta / Baja - Cause & diagnosis

Hi, I come to you to get more informations regarding patella alta (located too high), and baja (located too low). I made tons of searches, studies, but I wasn't able to find out why those patellas were located this way, is it genetic, related to puppy growth or something else ? I would like to know the cause (and if you have a source of some kind). I noticed that most of the time, when the patella is baja, it overlapses on the shin. Are there some cases when it doesn't overlapses on the shin while still being baja ? What do you think of those 3 dogs ? I know one is not ideal because it's a hip radiography, but we can see the patella is kind of high, does it seem like it may be patella alta ? The dog doesn't show or have any symptoms of anything, but the position makes me wonder about it. Also, the radiographies of the patella movement were not the same position as most pictures we can see on patella dog radiographies on internet, is that a problem ? The other two are sisters, what do you think about it ? One has had a ruptured cruciate ligament, and that's how patella baja was diagnosed, but the patella doesn't overlapse the shin in this case. There have been a few other cases of weaknesses in those areas, but different kind of problems, including another ruptured cruciate ligament in the ancestors / sisters / brothers. Thank you for your help !

Hello Im going to be honest and explain that 'patella alta and baja' are not terms I have ever come across in veterinary medicine, although they do have a meaning in human medicine and I remember from my schooldays that alta and baja mean 'tall and short' or 'high and low' in Spanish.  A google search brought up some results but a search of the UK Veterinary Times, a weekly publication of  over 25 years detailing research and veterinary news, which has a search function, does not mention it.  I am therefore a little unclear as to what aspect of the patella ligament is under discussion here - perhaps I have something to learn.  The patella sits in a groove over the knee joint, which can be seen at the end of the femur. It slides up and down within this groove when the knee opens and closes.  Good questions for your vet may be, 'What exactly do you mean when you say patella alta and baja?  How did you measure it? What impact do you think this is having on the way my dog moves their leg?  Furthermore, 'what evidence for assessing this in dogs is there?' and 'What evidence is there that this will cause a problem for my dog?'   Following this, you can have a conversation about whether surgical intervention is necessary.  You could also ask, on my behalf, whether Uk vets refer to this condition as something else. However, part of being a good vet is not to pass judgement on something that is not within your knowledge and therefore, if you brought this question into my veterinary surgery, I would be speaking to a referral specialist in order to try to shed light on this question and your vet may do the same.  I do know that the anatomy of different dogs' knees varies enormously (compare a St Bernard to a greyhound to a pug) so would not be surprised if there are genetic reasons dictating how high the patella sits when the knee is at a particular angle.   I will do some more research on your behalf and hope that something there gives you some ideas.