Sudden Pain and Lameness? Your Dog May Have a Ruptured ACL

One of the most common injuries a dog can get is a torn anterior cruciate ligament (ACL).  The tearing of the ligament happens in healthy athletic dogs as well as overweight dogs when they are running and suddenly change direction.  The ACL and the posterior cruciate ligament are two ligaments that cross each other as one travels from the front to the back of the knee joint, and the other travels from the back to the front. What does the ACL do?  This ligament is a fibrous band of tissue that attaches your dog’s femur with their tibia, making the knee joint a hinge.

What are the signs of a torn cruciate?  The joint becomes unstable, causing pain and usually a non-weight bearing lameness.  The cruciate ligament can also be partially torn, which can make it weaker than normal and lameness may be less severe or intermittent.  However, with time, the ligament nearly always tears completely.  Long term use of an unstable joint like the knee is a recipe for arthritis.  When a cruciate is completely torn, surgery followed by a rehabilitation program is usually prescribed.  Many surgeons are collecting a fat sample during the knee stabilization surgery and then injecting both knees with stem cells.  They feel that the stem cells help reduce the pain and speed up the healing process.  The non-injured knee is also treated since many dogs will tear their other cruciate in the future.  The uninjured knee will also be taking on more weight as the knee that has had surgery heals. For previous posts on cruciates see my blog on Feb 10, 2010.