front legs give out when walking/ambulating

Question
Lucky is a 4 year old Irish Setter/Border Collie mix.  Over the last few weeks, her front legs give out on her while walking and/or ambulating.  It has gotten progressively worse, and she'll no longer climb the steps.  She doesn't wobble or appear off balance, and I've checked for possibly ingrown toe-nails thinking maybe her paws hurt when she walks, but I don't see any problem.  I don't feel any deformities, she hasn't been hit by a car, there's no swelling, and she is not tender on palpation.  I haven't noticed any other symptoms that I can think to mention.  Any ideas?  Look forward to hearing from you soon!

Answer
Your best bet is a trip to the vet for an examination and x-rays.  This may be an arthritic problem but sounds more like a neurological problem.  I would also have her tested for tick-borne diseases especially Lyme Disease.  Certainly you can start her on joint supplements with Glucosamine, Chondroitin and MSM to see if that helps.  She may benefit from also seeing a acupuncturist and/or chiropractor.