Hi,

Welcome to Just Answer. I'm sorry to hear about Apollo's limping on that rear leg. At this point in time, a rear leg lameness as you are describing could be due to one of the following reasons.

1) Stifle/knee injury - this is in all honesty the most common. Could he have torn a cruciate ligament, or another ligament in the knee? Tearing or partial tearing of the anterior cruciate ligament is the most common. With partial tears, the animal can exhibit a temporary lameness and then after some rest seem to be as good as new. They will usually re-aggravate the injury, or tear the ligament completely. Your veterinarian can diagnose the problem by checking for a cranial drawer sign which may need to be done under anesthesia or sedation. Here is avery good link discussing an ACL tear further

http://www.VeterinaryPartner.com/Content.plx?P=A&S=0&C=0&A=1975


2) Orthopedic injury. This is an actual fracture of any one of the bones in the back leg. This is always a possibility and can usually only be confirmed by radiographs. The fracture may be such that an obvious swelling or abnormality is viewed and sometimes not. If he doesn't seem to be in pain, this would seem less likely.

3) General soft tissue injury - this is like a deep muscle bruise or twist of a joint - similar to a sprain or strain. Pretty common and usually gets better with time and rest.


In all honesty, with Apollo you have two options. Veterinary exam now to further evaluate the source of the lameness or give some time and rest to see if it improves. If choosing to rest and see how that helps - you need to restrict all activity to so that it has a good chance to not be further traumatized. A kennel is the best for this. This can be done for a day or two to see how he improves. If the limping persists, then an evaluation is definitely warranted.