What is veterinary Arthroscopy?

Arthroscopy is a technique for examining the inside of a joint using a tiny camera. This allows detailed assessment of the joint in a minimally invasive fashion, avoiding some of the risks and discomfort that can be associated with traditional, more extensive ‘open’ surgery. Sometimes arthroscopy is performed to gather information to help make a diagnosis and decide on treatment options and the outlook (prognosis). In other situations, arthroscopic surgery is performed to treat a particular problem.

The word arthroscopy comes from two Greek words, “arthro” (joint) and “skopein” (to look). The term literally means, “to look within the joint.” In an arthroscopic examination, an orthopedic surgeon makes a small incision in the patient’s skin and then inserts pencil sized instruments that contain a small lens and lighting system to magnify and illuminate the structures inside the joint. Light is transmitted through fiberoptics to the end of the arthroscope that is inserted into the joint. By attaching the arthroscope to a miniature video camera, the surgeon is able to see the interior of the joint through this very small incision rather than a large incision needed for surgery. The image is magnified up to 20x.

The video camera attached to the arthroscope displays the magnified image of the joint on a video monitor, allowing the surgeon to look, for example, throughout the knee (stifle) at cartilage and ligaments, and under the kneecap (patella). The surgeon can determine the amount or type of injury, and then repair or correct the problem, if it is necessary.

When is arthroscopy performed?

In theory, arthroscopy can be performed on any joint, but it is most commonly performed on the elbow for investigation and treatment of elbow dysplasia, and on the shoulder for conditions such as osteochondrosis, biceps tendon tears and ligament ruptures. Arthroscopy is also used on selected occasions in the knee (stifle), and less commonly the hip, wrist (carpus) and ankle (hock) joints.

Why is Arthroscopy necessary?

Diagnosing joint injuries and disease begins with a thorough medical history, physical examination, and usually X-rays. Additional tests such as an MRI, CT scan or ultrasound examination may be needed, as well. Through the arthroscope, a final diagnosis is made which may be more accurate than through “open” surgery (arthrotomy) or from X-ray studies.

Disease and injuries can damage bones, cartilage, ligaments, muscles, and tendons. Some of the most frequent conditions found during arthroscopic examinations of the joints in dogs are:

  • Loose bodies of bone and cartilage: OCD (Osteochondrosis / Osteochondtritis Dissecans) of the knee, shoulder, elbow, ankle (hock)
  • Inflammation: Acute and Chronic Synovitis – inflamed lining (synovium) in knee (stifle), shoulder, elbow, or hip
  • Bursitis: Inflammation of a sac-like structure that surrounds ligaments
  • Injury:
    • Shoulder: OCD, inflammation or tears of the bicipital tendon, rotator cuff injuries
    • Knee: Cranial cruciate ligament tears with instability, meniscal (fibrocartilage) tears, chondromalacia (softening, wearing or injury of cartilage)
    • Elbow: OCD, UAP and FCP associated with elbow dysplasia
    • Hip: Tearing of the ligaments or joint capsule, cartilage damage

Although the inside of nearly all joints can be viewed with an arthroscope, four joints are most frequently examined with this instrument. These include the hip, knee, shoulder and elbow. As advances are made by engineers in electronic technology and new techniques are developed by orthopedic surgeons, other joints may be treated more frequently in the future.

How is arthroscopy performed on dogs and cats?

Arthroscopy is performed with the animal under a general anaesthetic. The hair over the affected joint is clipped off and the skin cleaned, in a similar way to any other surgical procedure. Small incisions, or portals, are then made into the joint to allow introduction of fluid and the arthroscopic camera and instruments. Different sizes of camera are used depending on the joint involved and the size of the patient; the cameras range from 1.9mm to 2.7mm wide. Because the cameras and instruments are so small, the incisions into the joint only need to be a few millimetres long. As a result, any discomfort after the operation is minimised and recovery can be rapid.

When indicated, corrective surgery is performed with specially designed instruments that are inserted into the joint through small accessory incisions.

Initially, arthroscopy was simply a diagnostic tool for planning standard “open” surgery, known as “arthrotomy”. With development of better instrumentation and surgical techniques, many conditions can now be treated arthroscopically. Several disorders may be treated with a combination of arthroscopic and standard surgery:

  • Cranial Cruciate Ligament Injury in the Knee
  • Patella Luxation
  • OCD of the Shoulder, Elbow, Knee and Hock
  • Elbow Dysplasia: Coronoid Disease, UAP
  • Shoulder Injuries

After arthroscopic surgery, the small incisions may be covered with a dressing. Many patients need little or no pain medication from arthroscopy.

Before being released, you will be given instructions about care for your pet’s incisions, what activities to avoid, and which exercises should be done to aid recovery. During the follow-up visits, the surgeon will inspect the incisions and discuss the rehabilitation program.

The amount of surgery required and recovery time will depend on the complexity of the problem and what other procedures were also performed. Occasionally, during arthroscopy, the surgeon may discover that the injury or disease cannot be treated adequately with arthroscopy alone. More extensive “open” surgery (arthrotomy) may be performed while your pet is still anesthetized, or at a later date after you have discussed the findings with your surgeon.

What are the advantages to arthroscopic surgery?

  • The arthroscope can be inserted to areas of the joint not visible in a traditional “open “surgical evaluation.
  • In addition, the image is magnified up to 20 times on the video monitor, allowing for a more detailed evaluation of the joint.
  • Although arthroscopic surgery has received a lot of public attention because it’s widespread use in people, it is also an extremely valuable tool for canine orthopedic patients and is generally easier on the patient than “open” arthrotomy. Thus, one of the biggest advantages of arthroscopy is that it is a much less painful procedure than “open” arthrotomy.
  • Patients will use the limb earlier and better, with less loss of muscle tone and strength.
  • The onset and development of osteoarthritis may also be expected to be less compared to “open” arthrotomy.

Recovery and aftercare after your dog or cat has Arthroscopic surgery

Because arthroscopic surgery is minimally invasive, the recovery tends to be quick. Most dogs are discharged from the hospital within 24 hours of the procedure. There is inevitably some mild discomfort after the operation, but this usually subsides over a couple of days and is easily controlled with painkillers.

The small puncture wounds take several days to heal. Although the puncture wounds are small and pain in the joint that underwent arthroscopy is minimal, it takes several weeks for the joint to maximally recover. A specific activity and rehabilitation program may be suggested to speed your pet’s recovery and protect future joint function. Occasionally, oral and injectable supplements are recommended to treat inflammation (synovitis) or cartilage damage.

Most dogs will need to be restricted to short walks on a leash for a week or so to allow healing of the skin incisions; skin sutures are removed after 10-14 days. Depending on the underlying problem in the joint, additional aftercare may be needed, such as physiotherapy/hydrotherapy or ongoing management of osteoarthritis.

Risks and complications of Arthroscopy and arthroscopic surgery on dogs and cats

Theoretically, the risks of arthroscopy can include infections and anaesthetic complications, but these are extremely rare.