Dog Health: Knee Injuries
This article is from Dr. James St. Clair, DVM. Dr. J is a vet that specializes on canine recovery from orthopedic surgeries. He publishes the Home Rehabilitation Guide series for free on the web that provide step-by-step insturctions to dog owners to help their dogs recover properly from various major knee surgeries.
Knee injury is a common orthopedic condition in dogs. The anatomy of a dog’s knee makes it more prone to developing injuries or conditions that may interfere with their gait and mobility. A dog’s knee does not have interlocking bones that can provide adequate support to a dog’s body.
Despite this risk factor, a dog owner can help address the condition by taking a pro-active approach. Early detection of knee injuries in dogs is very important in order to avoid serious complications from setting in. When the knee joint becomes unstable, painful arthritis can quickly set in and may further aggravate the condition.
The dog’s knee is also known as the stifle. It is a joint that connects the bones of the upper and lower legs. Since it is a weight-bearing structure, the stifle contains some of the strongest ligaments in the body and they are arranged in such a way that they are able to maintain stability through a wide range of motions.
A dog’s knee is composed of a meshwork of ligaments and muscles. One of the major ligaments of the stifle joint is the cranial cruciate ligament (CCL) which is also called the anterior cruciate ligament (ACL). It facilitates forward movement of the lower region of the hind leg in relation to the upper part of the body. It also functions to limit the internal rotation of the knee. It is the cranial cruciate ligament (CCL) which provides the support and stability of the dog’s body.
When the cranial cruciate ligament (CCL) is injured, either partially torn or completely ruptured, what holds the knee joint in place are only the muscles and soft tissues, thereby making the joint highly unstable. A CCL injury is often suspected when there is sudden onset of lameness in dogs which fails to improve with time. Other manifestations include tip-toeing, favoring the affected limb, or not putting weight on it. When one knee is affected, it is common to see the other limb ruptured as well.
Damage to the CCL is primarily attributed to acute trauma or from a persistent recurring injury. Acute trauma usually occurs when dogs engage in strenuous activities like running, jumping, or romping while chronic damage is caused by abnormalities in limb and joint conformation, poor muscle tone, obesity, or neuromuscular incoordination. Aside from these commonly identified causes, recent research findings have shown that there is a higher incidence of CCL injuries in dogs which have been spayed or neutered and also those that are over four years old. Research studies have also discovered that prolonged corticosteroid therapy can also increase the risk of CCL injuries.
There are a number of treatments,both surgical and non-surgical,which have been identified to correct any type of CCL injury. Your veterinarian is the best person who can determine the best mode of treatment after thorough examination and evaluation. Non-surgical treatments include regenerative stem cell therapy and the use of knee braces. Surgical options include Lateral Suture Stabilization (LSS), Intra-capsular over-the-top stabilization surgery (ICS), Tibial Tuberosity Advancement (TTA) and Tibial Plateau Leveling Osteotomy (TPLO).
Many dog owners prefer TPLO because it has a faster recovery rate compared to other surgical techniques. Clinical observations have shown that about 50% of dogs that underwent TPLO surgery started to use the limb within 24 hours after it has undergone surgery and started putting weight on the affected limb within 5 days. Correction of CCL injuries using TPLO surgery has also been associated with lesser incidents of arthritis and an improved range of motion of the joint. TPLO surgery can also correct the sliding backward of the femur on the tibia bone, a condition known as the “drawer motion”. More than 90% of dogs that undergo TPLO surgery have been observed to recover from lameness and regain normal or almost a hundred percent function of the affected limb.
