Migrating Microchip

Hi there
I am a newbie. I have four rescues, one, 6yr old Golden Retreiver and three cats, aged 15, 8 and 5 months. My newest guy was found in the engine of a car brought to a dealership. The car had been driven twice with him inside. One trip for an hour and ten minutes from his home and the second, a mechanic test drive. Only when the mechanic had the car on the hoist and removed the oil pan did he see the little 8 week old guy in there. Totally unharmed. He said if he was a centimeter one way or the other, he would have been gone. Even after going through this incredible, terrifying ordeal, and surviving uninjured, the owner's didn't want him. This was beyond me!!! Needless to say, he is now in a loving home and the luckiest cat I know.
However - I now have a problem. I had him neutered three weeks ago and like most responsible owners, I also had him microchipped. The last week or so, I noticed a very hard lump on the back of his skull. Couldn't figure out what it was, and thought I would wait a while to see if it went away. Maybe he just got carried away with the others one day and had a bump. Anyways, I called the vet yesterday and he said he is sure it is the microchip. I take him in tonight to be certain. I read all kinds of things on the internet last evening and it is highly likely that a microchip will travel/migrate in their bodies, but out of tonnes of references saying it migrates generally horizontal or downward, even into the legs, I only found one brief reference to one going up. Has anyone ever heard of this?? It is obviously lodged between his skull and scalp and I worried that connective tissue may already be forming around it and it is there permanently. I worry that this may cause pressure on his skull as he grows. He is still only about 2/3rds adult size. I hate to think that this little guy amazing went through what he did in the car with no effects and here I am trying to do something good, and I give him something to maybe harm/mark him for good!! Augh! The bump is so noticeable because he is short hair, all white with the exception of about ten grey hairs, with pink pink skin and blue eyes. Oh yes, another lucky thing for him - despite his genes, he's not deaf, even though his mother and brother were!
Sorry for the ramble. Just a worried mom. Thanks all.

I can't help you with the microchip question but ...

thank you for rescuing him ! It's not the first time I hear about cats inside cars ... the techs where I used to work found one dead once , but another time , years ago , they found a kitten inside a fender , still alive !

What a lucky little kitty! He definitely needed some of those 9 lives to survive till his :angel: found him!

After three weeks, it's probably not too likely that connective tissue has cemented the chip in place. It also sounds like it's in a spot fairly easy to get to--so if the vet has any concerns about where it ended up, it should be surgically removable with a minimal scar. What a nerve-wracking thing to happen with your little guy, though :grouphug:

Let us know what the vet says tonight! :goodvibes:

Thanks Frenchy and Hazelrunpack;
I sure hope you are right about the chip not being cemented in place. If the vet suggests removing it because of where it has landed, I will definately do it, even though I so much hate that I would bring any more trama to this little guy.
That, then, brings up the question of, do I get a second one put back in?? Are my chances high, that it will migrate the same as the first? That's a question, the vet probably can't even answer. I just think this is such an odd scenario!!
Everything to do with my little guy, seems to be a one in a million chance.
Hopefully the wager is always on the positive side!:fingerscr
I will keep you in the loop.

Well it is quite different than I thought. Turns out the microchip has migrated a tiny bit from where it was put in, but that is not the cause of Diesel's lump. The vet said it is a bone spurr that was caused at some point in time by a chip in his skull, and as he grows the body is overcompensating by adding extra calcium to the chip and thus a lump that seems to be growing as he is. I said that when he was taken from the car, he had no blood or visible sign of injury, however, the vet said it could have happened with a force that may not have split the skin, but still chipped the bone. I find that kind of hard to believe. Diesel is white, so if there was any injury to him at all, since I have had him, it would have been readily visible. I am leaning to the idea that it may have been something happen, in his previous home - before he went for his wild ride. I don't see any kind of scar either. The vet says, for now, we have measured it and will wait to see how big it eventually gets as he becomes an adult. At that time, we will know if it is big enough to put enough pressure on his skull that would warrant surgery to remove it.
The vet put an incredible amount of pressure on it last evening, without a sound or movement from Diesel, so he determined it was not giving him any pain. One good thing!! I guess now it will be a wait and see game.

I'm glad it's not bothering him, at least. :fingerscr that it won't get any bigger.

As for bone chips without a visible wound--I'm a clutz and fall up the stairs a lot :o I never damage the skin beyond a bruise, but I have plenty of bone chips that ride slightly above the shin bone--you can feel them. So it's possible, just from a hard bump, to damage underlying bone without having an open wound in the skin. Typically this would occur in areas with just a thin soft-tissue covering, like a human shin, or perhaps a dog's skull :shrug:

I am kinda clutzy too. Probably full of chips for that matter - but never noticed... lol... Makes sense though.
:lightbulb: I'll have to buy him some brill cream to keep the hair from poking straight up, on top of it....lol
But you are right, main thing is, that he appears to have no pain and no other symptom other than the bump.
Thanks,