Knee arthroscopy is a surgical procedure in which a small, rigid, fiber optic camera and lens are inserted into the knee joint under anesthetic, allowing the surgical team to have direct-view access to the internal structures of the joint and to effect repairs and treatment. Prospective patients need to be aware of potential complications before undergoing knee arthroscopy.
Deep Venous Thromboses or Blood Clots
Deep vein thromboses, or DVTs, are blood clots that form in the venous system of the lower extremities. While there can be many different causes, such as blood coagulation disorders, there is a definite risk of clot formation after arthroscopic surgery of the knee.
Knee arthroscopy is performed under anesthesia; general or asleep, or spinal where the lower portion of the body is made numb. The surgery is conducted under bloodless conditions, aided by what is known as tourniquet ischemia, where the blood supply to the leg is cut off by the use of an inflatable cuff around the thigh. Tourniquet use, together with general relaxation from anesthesia and post operative narcotic pain medication usage, can help to create a scenario of minimal mobility after surgery and pooling of blood in the legs.
The real danger of DVTs is their ability to break away from the veins of the leg and travel to the heart and lungs, causing a condition known as pulmonary emboli, or PE which can be a catastrophic complication. As a rule, the incidence is typically low, as evidenced in a study published in the "Journal of Arthroscopy and Related Surgery."
Infection
As with virtually any surgical procedure, post operative infection can be a troublesome event when it occurs. In many instances, preventative administration of antibiotics is undertaken in the hopes of reducing the risk. Infection can occur as a result of many things; opportunistic microorganisms on the skin, compromised sterility of instruments, poor surgical technique and most prevalent, pre-disposing patient health concerns that raise risks such as diabetes, poor circulation and chronic smoking.
In an article published in the January issue of the "Journal for Arthroscopy and Related Surgery," Jack Bert, MD, orthopedic surgeon at Summit Orthopedics in St. Paul, Minnesota, reviewed approximately 3,000 cases of knee arthroscopy where antibiotics were, and were not used. The rate was .15 percent for those receiving antibiotics and .16 percent for those not receiving any. This study showed not only the insignificant difference between using antibiotics before surgery or not, but also the overall infection rates for knee arthroscopy were quite low.
Hemarthrosis
An abnormal collection of blood in the knee joint following surgery or injury is called a hemarthrosis. Normally, the only fluid found inside the joint is synovial fluid, which is the lubricating and nourishing fluid produced by the joint lining; the synovium. Post knee arthroscopic hemarthrosis is a real risk factor in this type of surgery and can cause considerable pain after the procedure if enough volume of blood collects there. Blood in the knee can also cause considerable inflammation and decreased mobility of the knee and in this scenario, is also a prime medium for bacterial growth, increasing the potential for infection.
Damage to Internal Structures of the Knee
In the course of performing knee arthroscopy, it is often necessary to insert rigid instruments into the knee---which is filled with sterile fluid---to expand the joint in order to accommodate these instruments. If the surgeon is not careful, inadvertent damage to the soft joint surface cartilage, nerves and blood vessels can easily occur. This is a highly preventable complication and lends itself to the skill and expertise of the surgeon performing the arthroscopy
Chronic Portal Leakage
Because knee arthroscopy is performed through tiny stab wounds called portals, versus incisions, these small wounds can develop chronic drainage of knee fluid as a result of incomplete healing. This complication can occur in spite of the use of staples or sutures to close the wounds, and on rare occasion, must be surgically enlarged in order to close the non-healing deeper layers.
References
- The American Academy of Orthopedic Surgeons: Knee Arthroscopy
- Knee Pain Info: Arthroscopy
- Journal of Bone and Joint Surgery: Arthroscopy; "no-problem" surgery
- Arthroscopy Journal: Incidence of DVT after Arthroscopic Knee Surgery
- Musculoskeletal Report: No Gain to Pre Op Antibiotics for Knee Arthroscopy
