Found it.....Here's the Link:
www.tiggerpoz.com
Hello & welcome....Are you sure it's not his foot? If not, then I'd go with a Torn ACL....They're very common.....Complete crate rest & no running, jumping, climbing, etc. can help them heal if they are partially torn....If it's a complete tear, surgery is usually necessary....
I'd have the knee xrayed and start some "Joint Supplements" immediately.....
I have a wonderful link about Torn ACLs, I'll have to dig it up...I'll get back with you....Karla
P.S. A good Vet can tell if it's an ACl problem with a leg exam....There's a certain way to manipulate the leg to tell...When one of mine was Diagnosed, his Dr. did it with an evaluation....We did an xray just to check for arthritis in the joint....His was an old injury that happened before I adopted him.....So Arthritis had already set in.......
We have managed with Joint Supplements and Anti-inflammatories as needed....He though, is a small breed.....Usually, large breeds need surgery to repair it.....However, after the healing process (Maybe 3 months), they're good to go.......
Two months and he is still favoring that leg would indicate it may certainly be something more then a pulled muscle. Although, I don't know how much activity he has been doing since then. Injuries can take a long time to heal and they really do need to rest the affected limb with limited exercise, like short walks, etc. At this point, I would take him back to the Vet (or another Vet) and possibly get an x-ray done to try to determine what damage has been done. There might even be a hairline fracture or something. This doesn't really sound like an ACL but it could even be hip related.