Dog Legs Bowed after excersize

My best friend recently purchased a 10 week old purebred Pit Bull puppy.
A couple of days ago she noticed that his front legs were bowing out. She says it's either one or the other front leg, or both. She thinks he gets way more excersize at her house than he did at the breeder, but is that the cause? She paid a handsome price for this boy and he is health guarenteed but they are growing attached!!
Has anyone had anything like this happen? She has a call into the breeder, but I told her I would post here for you all to see, Perhaps someone here knows what this is.
Thank you.

A couple of questions first......

What type of exercise/play and how much of the same does the pup get.

and

What food does she feed the pup.

Those would be my questions too. A 10 week old pup shouldn't be getting any kind of hard exercise. A few minutes of playing is enough.

Is that what "knuckling over" looks like? I've heard that's a vitamin C deficiency and can be cleared up. But I'd like to know the answers to the first questions first before saying this is what should be done.

Thanks for the replies.
She feeds him Maxium Nutrition Puppy Food. (but she has only had him for <2 weeks)
Also, she informed me this morning that it is not only when he plays with her other dogs, it is pretty much all the time that he does this. He will be nice and straight and all the sudden, his ankle joint almost look like they give out on him, he falls over his foot (as in the picture) and has to physically straighten them out again. He doesn't act like he's in any kind of pain, but it certainly looks uncomfortable when he does it. It is one foot, or the other, or both at the same time. One does not seem to be any better or worse than the other. She contacted the breeder, and here is what she said: Thank you again for all your help.

I know everyone says this, but if it were my dog... I would be seeking a vets professional opinion! Those front feet look very odd. I would want to know if this will be a life long problem and what is causing it in the first place.
Although I am not familar with pits, so what do I know.

I've heard of the term "knuckling over" but have yet to hear the term tight toes. Most often it is caused by poor nutrition while the pup is growing.

Feeding a quality food will help if it is caused by this. That and time. So the breeder is somewhat correct in his statement. If your feeding a quality kibble there should be no need for supplements.

On the other hand, if the breeder has a chronic problem with this as he seems to from his response, I would be a bit concerned about the overall health/quality of the pup and concerned about possible underlying problems.

The best way to find out is to get a thorough exam done at your vet.

I don't know anything about this site... Or the "remedies" that are reccommended, but there are some pictures of extreme knuckling over...

I couldn't find anything on "tight toes"

http://www.greatdanelady.com/articles/knuckling_over.htm

Interesting article. I've sent it on. That looks to be the issue. So it more than likely isn't a breeding issue? I found the breeders response very un-informative, and if it was my dog that I paid this much for, I'd be beyond upset...seemed to give the big brush off. Thank you all for your help. you are an awesome group!

Tell her to find a better food than Maximum Nutrition to start with. www.dogfoodproject.com is a great resource to learn how to tell the difference between "bad" and "good" foods.