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.
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
- 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.