September 19, 2017, by Community Pet Hospital
Nothing strikes fear into the heart of a dog owner than seeing Fluffy come back inside after a good romp holding up a leg. There are many different reasons your pet might be limping, but there are a few causes of rear limb lameness in dogs that you need to know about. Community Pet Hospital of Tigard is your source for help when your pooch is in pain.
Rear Limb Lameness in Dogs
Anything that hurts or otherwise inhibits the movement of a limb can cause lameness (limping). This can be related to bones, tendons, ligaments, or soft tissues such as the skin. There are many reasons that a pet might be limping on a rear limb.
We begin diagnosing a rear limb lameness in dogs by watching your pet move and performing a thorough physical examination. Sometimes radiographs (X-rays) or other tests are also necessary to arrive at a diagnosis. Common reasons a dog might be limping on a back leg include:
- An injured toenail
- A skin infection
- A broken bone
- A sprain or strain
- A ligament rupture (most commonly the cruciate ligament of the knee)
- A cartilage problem
- A joint infection
- A systemic illness such as a tick-borne disease
- A neurologic problem
Some problems are more common than others. Some may come on suddenly while others are more chronic. Some are caused by wear and tear, others a result of injury and still others are a consequence of development.
Two of the more often diagnosed causes of rear limb lameness in dogs, hip dysplasia and patellar luxation, have more to do with genetics and build than anything else. We diagnose them often enough that we feel strongly that our dog owners should be educated about the differences between these two rear limb issues.
The hip joint is what is known as a ball and socket joint. The pelvis forms a cup (socket) called the acetabulum that houses the ball portion of the upper femur. This allows this joint to have a unique range of motion and movement capability.
In some dogs, however, as this joint develops the ball and socket do not create a perfect fit. If this joint is loose (“lax”), it can create pain and impede motion. Long term this chronic instability leads to arthritis development in the joint.
Many things can contribute to the development of canine hip dysplasia including:
- Rapid growth
- Excessive nutrition leading to increased weight gain
- Large breeds such as the Labrador Retriever and German Shepherd are predisposed, but any breed can develop hip dysplasia.
Dogs with hip dysplasia will often have symptoms at an early age including bunny hopping while running, reluctance to rise or jump up on things, limping, and loss of muscle tone in the rear limbs. As arthritis sets in and the pet gains weight, symptoms often worsen.
Treatment of canine hip dysplasia depends greatly on the severity of the case and symptoms. Weight management and joint support may keep some patients happy while others may need surgery.
Patellar luxation is another common cause of rear limb lameness in dogs that has to do with the way the pet is put together.
The patella, or kneecap, is an integral part of the stifle joint (your dog’s knee). The patella is a little piece of bone that is embedded in a ligament that slides up and down the grooves in the front of the lower femur and upper tibia. The patella is meant to stay in a vertical plane, but sometimes things go awry.
A luxating patella is one that slips out of the groove and moves to the inside or outside of the leg. Medial patellar luxations are those the slip towards the midline of the pet, while lateral patellar luxations slide towards the outside.
Patellar luxations are very common in small breeds such as Yorkshire Terriers and Chihuahuas, but we also diagnose them in large dogs. A dog with a luxating patella will often skip or hold a leg up for awhile, then go back to normal without intervention. Severe patellar luxations may need surgical correction.
Oftentimes a luxating patella happens due to genetics and confirmation. A long patellar tendon, malformed tibia or femur, or a tight quadriceps muscle can force the patella out of place. Even underlying hip dysplasia can contribute, because, well, the hip bone’s connected to the knee bone.
Rear limb lameness in dogs is one of the more frequent issues we see at our hospital. Unfortunately, there is just no way of knowing what the cause is or how serious things may be without seeing your pet. If your dog is limping, please call us right away so we can get to work helping him or her feel better.