Usually I write only in finnish but now I have to make an exception.
What on earth is LTV?
There's a text on Finnish Kennel Club's page which tells us about LTV (writing is on finnish but here's free translation into english): "LTV (lumbosacral transitional vertebra) is common congenital and hereditary deformity of vertebra. Model of inheritance is unknown. LTV means vertebra which reminds sacral and lumbar vertebra. Transitional vertebra can be last lumbar vertebra (L7) and then it's called sacralization. It can also be first vertebra of sacrum (S1) and then it's called lumbarization. Abnormality can be either symmetrical (similar on left and right side) or asymmetrical (there's difference between left and right side). Diagnose is usually done by using a "hip X-ray"- from that view you can see sacrum and lumbosacral disc space from one direction ("above"). Some dogs might have abnormal amount of lumbar vertebraes: normally dogs have 7 lumbar vertebras and some dogs might have 8 or 6 of those. This form of LTV can be seen from lateral view ("spondylosis X-ray") where you can see whole lumbar spine along with sacrum.
LTV is found and common with many different dog breeds and there's research data made with GSD's of LTV being linked to back problems: it can expose for early degeneration of lumbosacral area which can cause pain in lower spine and in worst case paralysis of rear leags.
Finnish Kennel Club and it's breeding committee recommends that dog with any spine symptoms won't be used for breeding. All LTV changes (LTV1-LTV4) can be used IF dog has no symptoms and it's recommended for choosing partner with normal LTV result (LTV0). It's highly advisable that offpring will be X-rayed as well - this way we can get more information of inheritance and meaning of these abnormalities."
Grading scale
LTV0 - no changes
LTV1 - sacrum with S1 separated from the median crest of the sacrum or other mild abnormality
LTV2 - symmetric lumbosacral transitional vertebra
LTV3 - asymmetric lumbosacral transitional vertebra
LTV4 - 6 or 8 lumbar vertebras
LTV and other spinal abnormalities in whippets
First, I have to say that I'm not vetenarian - but I know little something about LTV and other spine issues. If you notice any errors could you please send me a message: essi.piironen(a)gmail.com.
I think that everyone knows that we have issues with heart (MMVD, sometimes DCM) and eyes (mainly vitreous degeneration) but we should also pay attention to spines.
There's 182 different whippets officially spine X-rayed in Finland (officially means that grading is done by certified vets and result public and can be fould from Finnish Kennel Club's Database - like OFA results in US). 64 (35,2%) had completely clear spine out of these 182 - 118 had some changes and those were between mild and severe abnormalities.
Here's stats from Finland (2014-2018):
I think that everyone knows that we have issues with heart (MMVD, sometimes DCM) and eyes (mainly vitreous degeneration) but we should also pay attention to spines.
There's 182 different whippets officially spine X-rayed in Finland (officially means that grading is done by certified vets and result public and can be fould from Finnish Kennel Club's Database - like OFA results in US). 64 (35,2%) had completely clear spine out of these 182 - 118 had some changes and those were between mild and severe abnormalities.
Here's stats from Finland (2014-2018):
Lumbosacral transitional vertebra: all examined: 182 kpl. LTV0 67 pcs, LTV1 84 pcs, LTV2 11 pcs, LTV3 9 pcs, LTV4 11 pcs |
Vertebral anomalies: all examined: 159 pcs. VA0 136 pcs, VA1 22 pcs, VA2 1 pcs, VA3 0 pcs, VA4 0 pcs VA0 is no abnormalities. |
Spondylosis: all examined 175 pcs. SP0 172 pcs, SP1 3 pcs, SP2 0 pcs, SP3 0 pcs, SP4 0 pcs |
All X-rays of this post are taken from different whippets. I have permission to use these. These dogs represent different lines from all over the world - so we definetly can't say that "oh, only THAT breeder" or "only THAT country" has spine problems or abnormalities on his/hers/its lines.
LTV abnormalities aren't caused by accident of injury - those are congenital.
LTV0, no abnormalities
Normal lumbar spine includes 7 vertebras (L1-L7) |
Normal sacrum includes 3 vertebras which are ossified together (S1-S3). |
Sacrum with normal median crest |
LTV1 - sacrum with S1 separated from the median crest of the sacrum or other mild abnormality
separated median crest of the sacrum. Yellow arrow points location of this separation. |
S4: sacrum is formed by 4 vertebras instead of 3, first tail vertebra (Cd) is ossified to sacrum. "Extra" vertebra is marked with yellow. |
Common reason for LTV1 on whippets is S4.
According to current knowledge LTV1 rarely causes any symptoms - but of course there's exceptions.
According to current knowledge LTV1 rarely causes any symptoms - but of course there's exceptions.
LTV2 - symmetric lumbosacral transitional vertebra
Symmetric lumbosacral transitional vertebra |
Symmetric lumbosacral transitional vertebra |
Incompletely ossified sacrum (S1-S2). This may be linked to symmetric or asymmetric lumbosacral transitional vertebra |
LTV3 - asymmetric lumbosacral transitional vertebra
Asymmetric lumbosacral transitional vertebra |
Asymmetric lumbosacral transitional vertebra |
Asymmetric lumbosacral transitional vertebra. |
Scewed pelvis is often associated with LTV3 and that may cause secondary hip dysplasia for both or other sides.
LTV4
Lateral view which indicates 8 lumbar vertebras. "Hip x-ray view" is still needed for specific diagnose. |
It seems like LTV4 is mainly caused on our breed by 8 lumbar vertebras (L8, lumbarization) instead of 6 vertebras (L6, sacralization) - at least I haven't seen or heard about any L6 yet.
And this is quite good thing beacause L8 rarely causes symptoms based on current evidences/observations of other breeds (mainly GSD).
And this is quite good thing beacause L8 rarely causes symptoms based on current evidences/observations of other breeds (mainly GSD).
Different kind of VA-abnormalities
Normal cervical spine includes 7 vertebras (C1-C2) First (C1: atlas) and 2nd (axis) differ from other cervical vertebras |
Block vertebra on cervical spine |
Normal thoracic spine includes 13 vertebra (ribs are attached to T-vertebras). |
Extra pair of ribs. Lumbar vertebra with ribs is marked with yellow. |
One extra rib. Sometimes change can be only on other side. |
According to current knowledge LTV and VA abnormalities are "related to each others".
Why would I take X-rays of my dog?
Young dog rarely suffers from any symptoms even if it had major changes on it's spine. You can't judge dog's spine based on it's topline. For example I have whippet with sloping loin and she has clear spine - and I have other whippet with more straight topline and she has LTV3. AND vice versa - I know dogs with straight toplines with clear spine results and shrimpy-like whippets with some abnormalities on their backs.
We need to remember that dog itself doesn't change before and after X-ray - his/hers bones are what they are with or without X-ray results. And even if there's some abnormalities you can use dog for breeding - we just need to remember that it's recommendable to find partner with clear results.
[At the moment Finnish Kennel Club has given different recommendation for whippets: it's also allowed to mate LTV1 to LTV1, not just LTV1 to clear. And there's no any registration restrictions with whippets based to health exams in Finland so these are only recommendations - breeders are making the final choices]
We need to remember that dog itself doesn't change before and after X-ray - his/hers bones are what they are with or without X-ray results. And even if there's some abnormalities you can use dog for breeding - we just need to remember that it's recommendable to find partner with clear results.
[At the moment Finnish Kennel Club has given different recommendation for whippets: it's also allowed to mate LTV1 to LTV1, not just LTV1 to clear. And there's no any registration restrictions with whippets based to health exams in Finland so these are only recommendations - breeders are making the final choices]
"My dog is running like crazy - so she/he must be completely fine without any spine abnormalities!" - wrong. Dog can run and race with abnormal spine. Even if dog has severe change it may never show any symptoms.
LC Ch & lordose on thoracic spine |
Finally I must say - the more we do these examinations the more we know about these conditions and their prevalence and heritability. And I bet that it's not harmful if owner truly knows what dog's spine status is.
PS. Hannes Lohi and his research group at Helsinki University are doing research about LTV on GSD's but they are collecting blood samples from other breeds as well:
Some links about LTV:
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