chihuahua has injured left hind leg.

Question
I was playing with my chihuahua, she was standing on her two hind legs, then
all of a sudden she starts whimpering and crying and running away with her
hind leg clutched to her side. I eventually calmed her down, my mom put ice
on it, and now my dog cant walk on her left leg. i tried moving it and she
doesnt seem to have any pain. Two days have gone by and she is using her
left leg now, jumping off things and even running. But when she is walking
she is limping. She puts all her weight on her right hind leg. I dont know if
her leg is broken, sprained or if it a muscle cramp. please help!!

Answer
You didn't mention her age but it sounds like she might have one of two things: Either she has a patella (knee cap) that is slipping in and out of the groove the knee cap rides in and then pops towards the inside, effectively 'locking' the leg, which is called a luxating patella, or she has injured her ACL which is her Anterior Cruciate Ligament.

Now in little dogs, luxating patellas is rather common. However, you should have the vet look it over and decide which one it is.

There are also two options. If it only bothers her once and a while you could probably let it go. However, if it pops out a lot, or seems to hurt her, she should have surgery on it. If it is a rare thing and she gets by fine the rest of the time, don't let someone talk you into a surgery she doesn't need.

Now an ACL is a different story and usually requires surgery. That would be a tear to the ligament and that renders the leg very unstable.

So you need to start with a good exam by the vet. An experienced vet can place their hands on a dogs legs and be able to tell which problem it is. Xrays should not be needed.

I hope this helps. Please let me know what you find out!