Septic Arthritis in Dogs

What Is Septic Arthritis in Dogs?

Septic arthritis in dogs is an infection that affects a joint, marked by harmful bacteria (most commonly), mycobacteria, fungi, or viruses. “Septic” denotes the presence of an infection, while “arthritis” signifies inflammation within the joint. Typically, septic arthritis stems from trauma, surgery, or a systemic infection in the bloodstream that travels to the joints.

Dogs afflicted with septic arthritis often experience rapid onset of pain. As bacteria multiply within the joint, inflammation ensues, causing degradation of the joint tissues. Timely and aggressive treatment is imperative to prevent chronic, long-term damage to the joints.

Fortunately, septic arthritis itself isn’t contagious, although the bacteria responsible for it may have the potential to spread. Among the various bacteria and pathogens that can trigger septic arthritis, MRSA (methicillin-resistant Staphylococcus aureus) is notably contagious and poses risks of transmission between pets and humans, as well as among humans.

Septic arthritis is relatively uncommon in dogs. Most cases occur in dogs with a history of penetrating joint injuries, recent orthopedic surgeries involving joint exposure, or compromised immune systems.

Recognized as a medical emergency, septic arthritis warrants immediate attention. Early intervention is crucial in mitigating joint damage.

Symptoms and Types

The symptoms of septic arthritis in dogs encompass both systemic indications arising from the bloodstream infection and localized manifestations stemming from joint pain. The prevalent symptoms include:

Lameness or discomfort in one or multiple joints
Increased warmth or swelling within the affected joint
Reduced or lack of appetite
Lethargy
Elevated body temperature

Causes

The causes of septic arthritis in dogs typically stem from various sources, including:

Penetrating trauma: Such as animal bites near the joint or puncture wounds in proximity to the joint, increasing the likelihood of septic arthritis.
Orthopedic surgery complications: Despite stringent adherence to sterile techniques during orthopedic procedures, postoperative complications may still arise, leading to bone or joint infections.
Systemic bacterial infections: Concentrated in the joint, they can contribute to the development of septic arthritis.
Immune system suppression: Diseases that weaken a dog’s immune system heighten the risk of septic arthritis.
Spontaneous occurrences: Some young animals may develop septic arthritis without any apparent trauma.
Underlying arthritic changes: Middle-aged, large-breed dogs might spontaneously develop septic arthritis in elbows with pre-existing arthritic conditions.

Prompt attention and veterinary care are essential, especially if a dog experiences a puncture wound near a joint or undergoes orthopedic surgery, to mitigate the risk of septic arthritis.

Diagnosis

To diagnose septic arthritis in dogs, veterinarians typically follow a structured diagnostic process:

Beginning with a comprehensive physical examination, veterinarians assess potentially affected joints, evaluate gait for signs of lameness, and check for heat or swelling, which are common indicators of septic arthritis. They also monitor for any fever, which may accompany the condition.
Blood work is often conducted to screen for systemic signs of infection within the bloodstream. Additionally, X-rays are utilized to rule out other orthopedic conditions that could affect the joint, such as fractures. In some instances, septic arthritis may be accompanied by osteomyelitis, a bone infection, which can be detected through visible changes in bone structure on X-rays.
Following the initial assessment, veterinarians may perform arthrocentesis, also known as a joint aspiration or joint tap. This procedure involves using a sterile needle to extract joint fluid and cells for microscopic examination. The collected fluid may also be sent to a microbiology laboratory for bacterial culture. Anesthesia is administered to ensure the procedure is pain-free for the dog.
If initial tests yield inconclusive results, further imaging studies such as ultrasonography or computed tomography (CT) scans may be recommended to provide additional insights into the condition.

This systematic approach allows veterinarians to accurately diagnose septic arthritis and tailor treatment accordingly.

Treatment

The treatment of septic arthritis in dogs typically involves aggressive antibiotic therapy. Dogs that are severely ill and exhibit systemic symptoms may require hospitalization until their condition stabilizes. In some cases, affected joints may need lavage, involving flushing with sterile saline.

Patients diagnosed with septic arthritis often receive prolonged courses of oral antibiotics. Follow-up visits are crucial to reassess joint health and monitor the progress of the infection. Veterinary professionals may repeat diagnostic tests to ensure the infection is resolving and the dog is on the path to recovery.

During home treatment, it’s essential to closely observe the pet for any changes in comfort, gait, and appetite. Antibiotics can sometimes cause gastrointestinal upset, so monitoring the dog’s appetite and stools while on medication is important.

It’s imperative to adhere to the prescribed antibiotic regimen and avoid discontinuing medication prematurely unless instructed by the veterinarian. Any changes in the dog’s response to treatment should be promptly communicated to the veterinarian. Consider discussing the addition of a probiotic with the veterinarian to maintain a healthy gastrointestinal balance while the dog is on antibiotics.

Recovery and Management

Your veterinarian may suggest rest for your dog during the healing process. It’s important to inquire about any activity limitations. If your dog isn’t experiencing lameness, engaging in low-impact activities like 15-minute slow walks is encouraged to maintain joint health. However, if your dog still favors the affected joint, restricted activity may be recommended to allow proper rest.
Anti-inflammatory medication prescribed by your veterinarian can help alleviate pain and inflammation. These drugs may improve your dog’s comfort, but it’s crucial to adhere to activity restrictions even if your dog appears to feel better. Joint healing may not be complete despite pain control.
Once your dog is cleared for normal activity, a gradual return to full function and range of motion is advised through physical therapy. This may begin with short walks and gentle exercises to strengthen the knees. Stairs, jumping, and running are gradually reintroduced as your dog progresses.
Physical therapy may also involve range-of-motion exercises, such as gentle circular motions of the rear legs, akin to pedaling a bicycle. Your veterinarian will tailor a physical therapy plan based on factors like the severity of the infection, the dog’s age, and the joints involved.
Recovery times vary based on factors such as the severity and location of the infection, whether it’s localized or systemic, and the promptness of treatment initiation. While it’s challenging to predict exact recovery durations, most dogs can regain full function within 4-12 weeks.
While most cases of septic arthritis are considered cured once resolved, dogs may still be susceptible to future episodes. Vigilance is essential in promptly addressing injuries involving joints and adhering to post-operative instructions to minimize the risk of complications.

Effective communication with your veterinarian and diligent adherence to treatment and rehabilitation protocols play pivotal roles in ensuring your dog’s optimal recovery from septic arthritis.