Orthopedic surgery and physical rehabilitation are fast growing fields in veterinary medicine, with more specialty practices
popping up in every city. As a technician, you play an important role in owner education when it comes to discussing orthopedic
diseases, postoperative care, medical management, and necessary physical rehabilitation.
One of the most common orthopedic diseases is a cranial cruciate ligament (CCL) tear or rupture. This condition can cause
patients extreme pain. If left untreated, it can cause meniscal tears and, in some cases, severe and sometimes debilitating
osteoarthritis. Treatment options include medical management, physical rehabilitation, surgery, or a combination of all three
Even if your clients are going to specialty practices for surgical intervention or physical rehabilitation, knowing the basics
of what they're going through will help build owner confidence in you and your practice. Registered technicians or properly
trained assistants can also perform many aspects of physical rehabilitation to increase their skills and grow the practice.
CCL ruptures and tears
Being familiar with the anatomy of the stifle joint will make it easier to understand what happens to the body after a CCL
tear, so let's briefly review the ligaments. The joint is stabilized by the medial and lateral collateral ligaments and the
cranial and caudal cruciate ligaments. The collateral ligaments limit the varus and valgus (side-to-side) movement of the
stifle. The cruciate ligaments prevent cranial and caudal drawer motion, hyperextension, and internal rotation, and they also
help limit varus and valgus motion. Although it's possible to injure any of these ligaments, CCL injury is most common.
Additional important structures within the stifle joint are the menisci, which are two C-shaped fibrocartilaginous structures
in the joint that act as a cushion between the femoral condyles and the tibial plateau. This cushion helps protect the cartilage
during weight-loading activity and helps absorb some of the shock from high-impact or concussive activity. The menisci also
help stabilize the femoral condyles on the tibial plateau.
An easier way to understand the role of the CCL is to learn how it stabilizes the knee during weight-loading activity. It
keeps the round femoral condyles from slipping caudally on the tibial plateau—think of a bowling ball on a hill—which would
then push the tibia cranially, otherwise known as tibial thrust. So a positive tibial thrust and cranial drawer sign are good indications of a cruciate tear or rupture. That, in combination
with palpation for a medial buttress (fibrous tissue accumulated on the medial aspect of the proximal tibia in most chronic
cases), gait analysis, and confirmation of joint effusion via radiographs will help confirm the diagnosis.
In some cases, the patient may also have a meniscal tear. Although this cannot be confirmed until the surgeon looks into the
joint, an audible popping sound or click within the stifle during manipulation can occur. These patients tend to be more painful
than patients with a cruciate tear without a torn meniscus.
In human anatomy, the CCL is called the anterior cruciate ligament (ACL). People often traumatically injure the ACL playing sports, but in dogs the CCL injury occurs from a slow, degenerative
breakdown of the ligament. Dogs stand at a much steeper tibial plateau angle, placing more responsibility and workload on
the cruciate ligament. So surgical repair for canine patients is drastically different from surgery in humans.
Although some primary care veterinarians perform surgical correction, orthopedic surgery is complex, so many patients are
referred to a veterinary surgeon at a specialty clinic. Surgical options for stabilizing a stifle with a CCL tear include
tibial plateau leveling osteotomy (TPLO), extracapsular imbrication (ECI), tibial tuberosity advancement (TTA), or a tight
Not every dog will be a candidate for every surgery, and depending on the surgeon's preference, he or she may recommend one
surgery over the other. No current studies show that one surgical technique is better than another for all patients. However,
the surgeon will be able to recommend the best option for the patient based on size, activity level, and owner lifestyle.
Some pet owners may opt for nonsurgical management of their dogs' CCL tears. Although this is not the most ideal recommendation
for canine patients, it's still an option. However, it's important to discuss realistic goals at length with the owner. These
patients may never recover to the same capacity as those that have had surgery, and osteoarthritis within the joint is more
likely to progress at an increased rate than it would in patients that have surgery. There is also about a 36 percent chance
of a meniscal tear without surgery.1
Nonsurgical management of a CCL tear typically consists of exercise restriction, physical rehabilitation, nonsteroidal anti-inflammatory
drugs (NSAIDs), and chondroprotectives. Nonsurgical options may be chosen because a patient is an anesthetic risk or suffers
from an infection or other metabolic illness that could delay or prevent healing. Owners may also have financial concerns.
Whether the client opts for surgical intervention or not, the patient's stifle will never be normal. The goal with surgery
is to get patients as close to 100 percent function as possible, but, with or without surgery, osteoarthritis is inevitable.