Dogs’ knee (stifle) joints include an essential ligament called the cranial cruciate ligament (CCL). It is known as the anterior cruciate ligament in individuals (ACL). The ligament is crucial in maintaining the stifle’s stability while under weight. It limits how far forward the shin bone (tibia) can move in relation to the thigh bone (femur).
Where on a dog is the CCL located?
A connective tissue in the knee called the CCL stabilizes the lower leg’s connection to the upper leg. It joins the tibia, the bone that lies below the knee in a dog, to the femur, the bone that lies above.
Overexertion during several types of greater impact activity frequently results in CCL injuries in canines. Similar to human athletes who frequently tear the CCL in their knees, athletic dogs are more likely to sustain CCL injuries. A quick action or jumping off the bed might cause some pets to rupture their CCL.
How do you tell if your dog’s CCL is torn?
An vital ligament in the stifle joint (knee) is torn, causing partial or total joint instability, discomfort, and lameness. This is known as a cranial cruciate ligament (CCL) rupture. Ligaments that have been torn retract, do not mend, and cannot be fully restored. Degenerative joint degeneration and damage to connective tissues are frequent outcomes of untreated injuries.
The CCL connects to the tibia, crosses the stifle joint, and links to the femur (thigh bone) (shin bone). The CCL inhibits internal rotation and hyperextension and stabilizes the tibia. Between the femur and tibia, there is a piece of cartilage called the meniscus that serves as a gliding surface and serves to cushion impacts. When the knee is unstable due to a CCL rupture, the medial meniscus may tear.
The most frequent cause of degenerative joint disease in the stifle joint and one of the most frequent orthopedic traumas in dogs is CCL rupture. Although it can happen in dogs of all sizes, CCL rupture is most common in large and giant breeds. Cats are also susceptible to CCL rupture, albeit it happens less frequently.
In 80% of cases, deterioration and rupture with a chronic beginning (typically brought on by aging) affect dogs between the ages of 5 and 7. In dogs younger than 4 years old, acute onset (tear brought on by injury) is more prevalent. Chronic rupture happens when the ligament has aged-related degeneration. Degenerative joint disease manifests as the fibers deteriorate and partially tear, the joint becoming unstable. The CCL finally totally tears after a partial tear.
Crepitus, or the sound of bones rubbing against each other, decreased range of motion, the “sit sign,” or the extension of the back leg while sitting, pain when the stifle joint is touched, resistance to exercise, limited mobility or extension, stiffness after exercise, swelling, a thick or firm feeling in the joint, and a tendency to lean to one side of the body when standing are all signs of a ruptured CCL. The movement of the misaligned joint after the ligament has been torn causes more injury, inflammatory reactions, pain, and ultimately degenerative joint disease. A pop or snap may be audible when the animal walks if the meniscus is torn.
A clinical examination and medical history are part of the diagnosis (information about lameness and injury). The joint’s range of motion is examined by the veterinarian. The diagnosis of CCL rupture is unmistakable with the cranial drawer sign. Because of the potential for extreme pain from a ruptured CCL and the possibility of muscle tension limiting joint motion, anesthesia may be required to move the limb to the required amount. Radiography (x-ray) may indicate a partial tear or a complete rupture, but it cannot confirm either.
The goal of treating CCL rupture is to reduce discomfort and improve function and mobility. Surgery is frequently accompanied with conservative therapy (weight management, rest, medication), but it is also an option for dogs and cats who weigh less than 25 pounds. However, lameness can persist until surgical correction, and a quicker development of arthritis is anticipated.
For dogs over 25 pounds, surgery is the recommended course of action. Even while it might not fully restore function, if done soon after the injury, it yields positive outcomes. Degenerative joint condition will not completely disappear after surgery (arthritis). There are several effective surgical treatments available. The surgical method utilized to restore the damaged ligament’s function depends on the surgeon’s experience as well as the breed and size of the dog.
In the extracapsular imbrication procedure, the CCL is replaced by a thick nylon suture that is passed through the joint from the outside of the femur to the tibial crest. Scar tissue develops in the days and weeks following surgery, adding to the stability of the joint.
The tibial plateau leveling osteotomy (TPLO) modifies the biomechanics of the stifle joint so that the CCL is no longer required for joint stability. The femur cannot slide off of the tibia without surgically altering the angle of the tibial plateau. Most dogs recover quickly, and most can move the limb within a week. According to reports, dogs over 35 pounds fare well with this difficult procedure.
Following surgery, the animal must be kept inside with its activities carefully restricted for a period of time. In order to avoid weight gain, the diet should be changed. At first, the pet is just let outside to relieve itself. After a 6-week follow-up, you can progressively increase your subsequent exercise. Usually, 2-3 months following surgery, normal exercise is resumed.
Up to 15% of individuals need further surgery to fix meniscus injury. Within 18 months of surgery, up to 40% of dogs rupture the CCL in the other rear limb. Surgery is delayed until the repaired joint has fully recovered if the CCL in the other stifle joint is ruptured. In more than half of the cases, full function is restored, making the prognosis good to excellent. The long-term prognosis is significantly impacted by the occurrence of degenerative joint disease.
After rigorous exercise, pets may still feel stiff and lame, especially if they have advanced degenerative joint condition.
The American College of Veterinary Surgeons website has further information about Cranial Cruciate Ligament Rupture as well as other frequent surgical conditions in dogs and cats.
Do dogs with a torn CCL experience pain?
The definition of “cruciate” is “to cross across” or “to make a cross.” Each stifle (knee) joint contains two bands of fibrous tissue called the cruciate ligaments. In order for the knee to function as a secure, hinged joint, they link the femur and tibia (the bones above and below the knee joint) together.
The knee joint has two ligaments that cross over one another in the middle, one running from the inside to the outside and the other from the outside to the inside. The ligaments are known as the cranial and caudal cruciate ligament in dogs and cats. The most frequent knee injury in dogs is a cranial cruciate ligament tear or rupture.
The anterior and posterior cruciate ligaments are the name given to the ligaments in the human knee, which is anatomically identical to the dog knee. A common knee injury among athletes is a ruptured anterior cruciate ligament.
How does a cranial cruciate injury occur?
The knee joint is a hinge joint by definition of its anatomy. Because there are no interconnecting bones in the joint, it is relatively unstable. Instead, a number of ligaments, particularly the cruciate ligaments, hold it together. These ligaments permit it to move back and forth like a hinge but limit its ability to move side to side.
Trauma and ligament deterioration within the joint are the two most frequent causes of cranial cruciate rupture. An injury to the knee joint caused by twisting is known as an acute or traumatic cruciate rupture. When a dog (or athlete) is running and abruptly changes direction, this most frequently happens. As a result, the knee joint bears the bulk of the body’s weight, putting excessive rotational and shearing pressures on the cruciate ligaments. Usually, the anterior or cranial (front) ligament is harmed by this injury. The knee joint becomes unstable as a result of a cruciate ligament rupture, which typically causes excruciating pain and lameness.
The progressive weakening of the ligaments brought on by repetitive trauma or arthritic illness results in a more chronic form of cruciate injury. Initial lameness may only be modest and sporadic as the ligament is strained or partially ripped. The situation gradually deteriorates with continuing use of the joint until a total rupture takes place.
It seems that obese dogs are more likely to get a cruciate rupture. In these dogs, a little trauma to the knee, such as tripping over a rock while walking, may cause the injury. Dogs who have luxating patellas (see handout “Luxating Patella in Dogs”) or other knee issues may also be more prone to rupturing their cruciate ligaments. When a dog tears one cranial ligament, they are more likely to tear the cranial cruciate ligament in the opposite knee.
How is it diagnosed?
The typical history of traumatic cruciate rupture is that the dog was sprinting and then abruptly halted or screamed out, losing the ability to bear weight on the injured leg. Many animals will “toe touch” and only put a little weight on the hurt limb.
Your veterinarian will attempt to mimic a specific movement, known as the cranial or anterior drawer sign, during the lameness assessment. The tibia (lower leg bone) moving abnormally forward in front of the femur (thigh bone) is a sign of laxity in the knee joint. It might be essential to give the dog a sedative to help it calm so the doctor can do this test. Radiographs (X-rays) and other diagnostic procedures may also be required.
Is other joint damage common?
Menisci, or fragments of cartilage, are located inside the knee joint. As shock absorbers between the femur and tibia, the menisci. When the cruciate ligaments tear, the menisci are frequently harmed. Usually, they are fixed concurrently with the ligament operation.
Is an operation always necessary?
If a dog is severely restricted in their activities, such as by being placed in a cage for six weeks, they can recover without surgery if they weigh less than 10 kg (22 lbs). Surgery is typically needed to stabilize the knee in dogs weighing more than 10 kg (22 lbs). Unfortunately, the majority of dogs will eventually need surgery to repair this excruciating injury. The ideal course of treatment for your dog should be decided in consultation with your vet.
What does surgery involve?
After a cruciate rupture, the knee joint is stabilized using a variety of surgical procedures. In order to stabilize the joint and stop aberrant motion, the surgeon examines the joint, removes any remnants of the ruptured ligament, and, if necessary, repairs the menisci. The artificial ligament is typically inserted outside of the knee joint capsule (known as a “extracapsular repair”). For more details, refer to the handout “Cranial Cruciate Ligament Repair: Extracapsular Repair and TightRope Procedure.” A tibial plateau leveling osteotomy (TPLO) or a tibial tuberosity advancement are two more recent surgical procedures (TTA). For larger, more athletic canines, both are particularly advantageous. Your pet’s best course of therapy will be discussed with your veterinarian. For more information on these operations, refer to the handouts “Cranial Cruciate Ligament Repair: Tibial Plateau Leveling Osteotomy (TPLO)” and “Cranial Cruciate Ligament Repair: Tibial Tuberosity Advancement (TTA)”.
Is post-operative care difficult?
For six to eight weeks following surgery, it’s crucial that your dog engage in minimal exercise. If a TPLO or TTA has been carried out, the activity limitation can be less severe. Within three months, the limb should resume normal function if you can follow your veterinarian’s advice.
It’s crucial that your dog rest for six to eight weeks following surgery.
Unfortunately, arthritis is likely to form in the joint as your dog ages, regardless of the method employed to stabilize it. If the dog has surgery, arthritis develops more gradually and to a lesser extent. The start of arthritis in your pet may be delayed with weight control and nutritional supplements like glucosamine/chondroitin (for more information on this supplement, read the handout “Glucosamine Chondroitin Combination”). After surgery, many dogs may need physical therapy to hasten healing and minimize complications. Prior to surgery, your veterinarian will go over the suggested post-operative care for your pet with you.
Is obesity such a problem?
Dogs who are obese or overweight are more likely to experience cruciate ligament tearing or rupture. The post-surgical recuperation period will be substantially longer if your dog is overweight. The risk of injury to the opposite knee is also significantly increased by obesity, particularly during the healing process. In order to ensure a quick recovery to normal function and as a preventative precaution to help shield your dog from this crippling damage, weight loss is as crucial as surgery. A suitable weight-loss strategy for your pet can be created with assistance from your veterinarian.
With a torn CCL, can a dog walk?
Our (human) knees’ center is made up of a thin connective tissue called the anterior cruciate ligament (ACL).
The cranial cruciate ligament (CCL) in dogs is a connective tissue that joins the bone below the knee (the tibia) to the bone above the knee (femur). The CLL can be compared to a “dog ACL,” and you’d be correct.
When comparing the two, the most significant difference is that dogs’ CCLs are always load-bearing due to the fact that they never flex while standing. This “ACL in dogs” is therefore more susceptible to damage than the ordinary human’s ACL, and a dog’s CCL must naturally withstand more strain.
What are the differences between ACL injuries in people and CCL injuries in dogs?
Regular everyday use should not cause an ACL tear; instead, an acute trauma from a sudden movement, such as a jump or direction shift, causes ACL injuries. Dog CCL injuries typically develop over time, getting worse until they result in a tear.
Alright, I now understand what CCL injuries in dogs are, but how do I know if my dog has torn their CCL?
A dog with a torn CCL will normally exhibit stiffness, which is usually most obvious after resting after exercise, as well as difficulties getting up, jumping, and/or walking without a limp.
On a mildly wounded leg, carrying on with activities will make the injury worse and make the symptoms more obvious.
Dogs with a single torn CCL often start favoring the unharmed leg, which frequently results in the injury of a second knee. 60% of dogs who suffer only one CCL lesion will shortly suffer another injury to the other knee.
Ok, but can a dog live with a torn “dog ACL”?
A non-surgical approach for treating a dog’s ACL or, more precisely, CCL injury is the use of a knee brace. In certain dogs, this may assist to stabilize the knee joint. A knee brace’s support provides the ligament time to scar over and heal itself. When coupled with limited activity, using a knee brace to treat CCL injuries in dogs may be effective.
When should I consider “dog ACL” surgery?
Consult your veterinarian to determine whether surgery is appropriate for your dog. Depending on the breed, age, and size of the dog, different CLL mending operations have varying degrees of preference. For your dog’s particular requirements, your veterinarian can suggest the best “ACL” surgery.
Please take note that the information in this page is for informational purposes only and does not constitute medical advice for animals. Please schedule an appointment with your veterinarian for a precise diagnosis of your pet’s illness.
