Like us, dogs have knees and there are two ligaments that help to hold and stabilise the knee joint. These ligaments are the cranial (anterior) cruciate and the caudal (posterior) cruciate and they cross over one another within the knee joint helping to secure the thigh bone, knee cap and shin bone together. Sometimes these ligaments tear and this is called a rupture. When the tear occurs the tibia moves freely from under the femur and it is this movement and rubbing that causes the pain. You will probably have seen athletes or sportsmen or women pull up suddenly and be in considerable pain after a ligament has ruptured. It is very similar for dogs and they will usually show lameness in a rear leg. Whilst not life threatening, it is extremely painful and needs immediate veterinary treatment. Failing to get treatment can cause arthritic changes that can lead to long term lameness.
So what causes a cruciate ligament to rupture and what can you do to help prevent it?
Sometimes it is just their sheer athleticism and over exuberance that can cause the tear. Healthy dogs might land wrongly from a jump, turn too quickly or just over stretch. Overweight dogs are at greater risk due to the excess weight carried and weakened joints. Over time degenerative forces acting on the knee joint can also lead to a tear. Certain breeds are more prone to cruciate rupture so it is likely genetics play a part too.
So what will your vet do?
Initially your dog will be examined in a consultation and the vet will manipulate the leg to try to establish exactly where the pain is happening. Watching how your dog walks (its gait) will also assist in making a diagnosis for a cranial rupture. If your vet thinks it is a cranial rupture they will likely manipulate the femur and tibia to check for instability. Something they will look for is a cranial draw sign where the tibia moves forward independently of the femur. Also, a test called the tibial thrust will be performed. If the signs are not clear then your dog may need to have x-rays .
In the majority of cases cruciate injuries will require surgery, but your vet may consider a more conservative option first with pain relief, anti inflammatory drug medication and a number of weeks of cage rest. The most common surgical treatment at Cherrydown is a TPLO (Tibial Plateau Levelling Osteotomy) which is conducted by our orthopaedic specialist J.B. Lefebvre. It is a complex operation and involves altering how the knee joint works to allow it to function without the cruciate ligament. During the operation the tibial plateau is rotated and a metal plate inserted to keep the bone in its new position. Over several weeks and with the dog restricted to cage rest only, the bone will heal into the new position. Following cage rest, further examination and x-rays will be required to make sure the surgery was a success and the joint is healing properly. Successful surgery is usually long lasting and dogs can go on to lead a normal active life.
What are the costs?
Where surgery is required there are considerable costs involved due to the complexity of the operation. If complications occur this will add to that cost. At Cherrydown we aim to cap surgery prices in advance and you will be given a fixed price to better enable you to manage your finances. If you are a client of Cherrydown and your pet is insured then you may be eligible for Direct Insurance* where we will foot the bill until your insurance company pays out. Typically a TPLO operation will cost between £2500 and £3000 and this is one of the reasons we strongly recommend that pets are insured and that the policy will cover at least this amount. Cruciate ligament ruptures, hip and elbow dysplasia and fractures are fairly frequent occurrences among dogs and each of these can cost a significant amount for treatment. Without insurance would you be able to meet the cost to give your best friend the best chance of a full recovery?
