Weakness in front legs

Question
My 7 week-old Husky mix puppy started limping two days ago. Once she gets up from sleeping she runs around and plays for a few minutes, then she starts limping and can hardly walk. She stops dead in her tracks and lays down because her front legs hurt her. I also have her mother and right now her mom is trying to wean her by biting her face and legs when she starts to nurse- but not too hard. She also has started shaking, I think from hte pain. Do you know what could be wrong with her? Is it her mom biting her legs that is causing this?

Answer
It is theoretically possible that the mother nipping at them could cause inflammation and/or pain in the joints.  Normally the mother will not bite hard enough to hurt the pups but in a young or inexperienced mother some injury can be seen.  

There is a syndrome in larger breed dogs HOD (Hypertrophic Osteodystrophy) leading to leg pain.  It is usually starts showing signs during the growth phases of 4-7 months of age, so she is a bit young to be showing this already.  However your veterinarian would be able to do x-rays to rule this our or diagnose it.

Patellar luxation would be another possibility.  In PA the kneecap slips out of the groove that it standardly lies in and bars normal bending of the limb.  Your veterinarian would be able to check this via physical exam.

My humble apologies for the delayed response as family illness had kept me from availability.