Laterally luxating patella plus ruptured cruciate

RE: Laterally luxating patella plus ruptured cruciate

Julian Earl — Sat, 18 May 2019 13:32:11 GMT

[quote user="Thomas Johnson"]I've seen it in giant breed dogs, not uncommon to get a history of the dog being walked on the lead at the owner's side and suddenly going lame, I once saw a dog where both had gone at the same time. I agree a lot less common in dogs under 40Kg.[/quote]

Thanks Thomas. Yes, in such cases it is hard t believe that there is no pre-existing deterioration in the ligament. But even with pathology in the ligament I think a twist exertsthe correct force on the ligamentcause it to snap. Maybe if weak enough, the walking motioncauses eough twisting to do th job?

What about Rottwelers and Golden Retrievers? Are there any known predispositions for their cruciates to rupture more easily than other dogs? I think that there must be some inherent weaknessif in their cruciates to explain the prevalence of the condition in those breeds. Unless it is their gait encouraging a twisting action in the hind legs? Perhaps caused by hip disease? Also Jack Russells seem to be susceptible IME. In these it might be an excitable nature, bandy hind-legs and their gait as well? JRT- susceptibility is just my suspicion; I have no statistics to bac this up.

I often said to owners that CCL-rupture is the most common major injury that I have seen in dogs, far more common than broken bones! There must be a reason for this in the structure of dogs?

RE: Laterally luxating patella plus ruptured cruciate

Thomas Johnson — Mon, 13 May 2019 18:49:13 GMT

[quote user="Julian Earl"]

I cannot recall ever seeing a case that had not been reported as having jumped, been running/chasing before immediately becoming 10/10 lame!

[/quote]

I've seen it in giant breed dogs, not uncommon to get a history of the dog being walked on the lead at the owner's side and suddenly going lame, I once saw a dog where both had gone at the same time. I agree a lot less common in dogs under 40Kg.

RE: Laterally luxating patella plus ruptured cruciate

Julian Earl — Mon, 13 May 2019 18:31:11 GMT

[quote user="Thomas Johnson"]For those that have had an obvious acute onset to the lameness from a cruciate rupture after a known episode of trauma I suspect that there was already some degeneration of the ligament which has weakened it, and then the dog does something that puts more strain through it than normal running or jumping, but that a non-degenerate ligament would cope with, and it snaps.[/quote]

I cannot disagree with that. I am open-minded about pre-existing disease/weakness in the ligament but I doubt that this is always the case. If so, the ruptures would be more common in older dogs whereas IME, young dogs are just as prone if not more so , presumably due to greater activity levels? I cannot recall ever seeing a case that had not been reported as having jumped, been running/chasing before immediately becoming 10/10 lame!

RE: Laterally luxating patella plus ruptured cruciate

Anthony Todd — Mon, 13 May 2019 17:21:58 GMT

[quote user="robloxley"]Google is your friend :) [/quote]

Too true, too thick to think of it myself.....

https://onlinelibrary.wiley.com/doi/abs/10.1053/jvet.2003.50023

Histologic Changes in Ruptured Canine Cranial Cruciate Ligament

etc

Might settle the "prior degeneration" argument??

RE: Laterally luxating patella plus ruptured cruciate

Rob Loxley — Mon, 13 May 2019 17:07:26 GMT

[quote user="Anthony Todd"]There must be some histology somewhere showing the state of the ruptured canine cruciate?[/quote]

Google is your friend :)

RE: Laterally luxating patella plus ruptured cruciate

Anthony Todd — Mon, 13 May 2019 16:57:42 GMT

BITD in NZ it was sheep dogs flying flat out through a 7 wire fence and catching one hind leg....

There must be some histology somewhere showing the state of the ruptured canine cruciate?

RE: Laterally luxating patella plus ruptured cruciate

Thomas Johnson — Mon, 13 May 2019 16:44:22 GMT

[quote user="Rob Davis"]

[quote user="Julian Earl"]In canines, IME, there is always an incident of landing on the affected leg eg from a jump in the air, jumping from a car other height, or just whilst running or playing of course.[/quote]

I disagree. I think in most dogs the cruciate disease is a result of degeneration of the ligament over a period of time, with conformation, obesity etc adding to the liklihood of problems. I think they have rarely had the classic "foot down a rabbit hole" type injury.

[/quote]

For those that have had an obvious acute onset to the lameness from a cruciate rupture after a known episode of trauma I suspect that there was already some degeneration of the ligament which has weakened it, and then the dog does something that puts more strain through it than normal running or jumping, but that a non-degenerate ligament would cope with, and it snaps.

RE: Laterally luxating patella plus ruptured cruciate

Anthony Todd — Mon, 13 May 2019 15:59:43 GMT

[quote user="Sarah Mark"]The other stifle has a lat lux pat but cruciate is intact. Thanks everyone, helpful stuff![/quote]

I was thinking that the insurance co. might therefore say the pat. luxations are therefore congenital??

RE: Laterally luxating patella plus ruptured cruciate

Rob Davis — Mon, 13 May 2019 14:29:41 GMT

RE: Laterally luxating patella plus ruptured cruciate

Julian Earl — Fri, 10 May 2019 11:40:56 GMT

I agree with giving a vague reply rather than a definite yes or no. But you could indicate that those breeds known to have susceptibility to CCL-rupture are not the same as those breeds with the tendency for a luxating patella. CCL-rupture is a twisting injury, as in football players and netball players on the human front . In canines, IME, there is always an incident of landing on the affected leg eg from a jump in the air, jumping from a car other height, or just whilst running or playing of course. As someone points out, the moment of injury will not necessarily be observed by the owner though. I think that you have to reason your way through and surely they will see the logic of your suggestion? It is the owner who has to provide the precise circumstances of the injury not you, because your version would necessarily be secondhand. In terms of their question all you can do is proffer your experience and knowledge Good luck with this.

RE: Laterally luxating patella plus ruptured cruciate

grumpyoldman — Wed, 08 May 2019 09:41:29 GMT

Around 50% of the current French Bull dog plague seem to have grade1-2 medial patellar luxations but no lameness . Most remain unmolested for this alone, and we do not have a queue of 3-6 year olds waiting for CCL surgery. When they are 6-9 that maybe a different story, depending how many get that far.

RE: Laterally luxating patella plus ruptured cruciate

Lucy Fleming — Wed, 08 May 2019 09:08:03 GMT

This made me curious so I did a bit of googling research and it seems that a connection between medial patella luxation and cruciate ligament rupture is suspected (but not proven):

"Medial patellar luxation and rupture of the cranial cruciate ligament are intertwined in several ways. It is estimated that at least 15% to 20% of dogs with patellar luxation will eventually rupture their cranial cruciate ligament (1). This may be due to a combination of 3 factors: First, dogs with significant patellar luxation usually have internal rotation of the tibia, which puts stress on the cranial cruciate ligament. Second, the quadriceps musculature-patella-patellar tendon mechanism normally provides cranial stability to the stifle joint. In the dog with patellar luxation, a good portion of this mechanism is deviated medially, thus offering less resistance to forces that would tend to subluxate the proximal tibia cranially. Third, cartilage erosion and degenerative joint disease may create an environment in the stifle that promotes degeneration of the cranial cruciate ligament"

Information about lateral luxation is even more scarce. I tend to agree with others that it's not really possible for a GP vet (or perhaps even an orthopaedic specialist) to say. Connected? Perhaps. One causing the other? Not that simple.

The first link is the paper that the above quote is taken from, the second doesn't mention CrCL rupture but has a nice diagram illustrating the above. They both should be open access.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1524842/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6055913/

RE: Laterally luxating patella plus ruptured cruciate

Sarah Mark — Wed, 08 May 2019 08:44:23 GMT

The other stifle has a lat lux pat but cruciate is intact. Thanks everyone, helpful stuff!

RE: Laterally luxating patella plus ruptured cruciate

Dinu Catilina — Tue, 07 May 2019 21:42:39 GMT

I generally word these things something along the lines: I have no evidence that there is a connection between the two conditions. It's up to the insurance company to do whatever they want with my statement.

RE: Laterally luxating patella plus ruptured cruciate

Anthony Todd — Tue, 07 May 2019 16:23:39 GMT

What's the other stifle like?

IME a luxated patella "protects" the cruciate in that the dog doesn't exactly leap about much?

RE: Laterally luxating patella plus ruptured cruciate

Beats — Tue, 07 May 2019 16:14:40 GMT

I would answer what I know to be true and give my personal opinion (clarifying that that is what I'm offering), where I do not know the truth.

On a hypothetical case, not knowing the specifics, I might consider:

Are the two connected?

Both conditions are affecting the same stifle joint.

If yes, did the lux pat cause the ruptured cruciate?

Unknown. The pathophysiology of cranial cruciate ligament disease is not sufficiently understood to answer this question with confidence. It is a reasonable supposition that the lux pat may have been a factor in the cruciate ligament failure, however it is also a reasonable supposition that it was not a sufficient cause in its own right.

I consider it my place to provide reasonable factual information to an insurer, however I don't consider it my place to adjudicate between an insurer and client (ex- or otherwise).