The benefits of less-invasive knee replacement surgery may not be as dramatic as some direct-to-consumer advertising may claim, but the procedure has resulted in less scarring, diminished pain and faster recoveries for select patients.
At a panel briefing of the American Academy of Orthopaedic Surgeons' 73rd Annual Meeting, experts discussed the pros and cons of the increasingly popular procedure, how orthopaedic surgeons are attempting to meet patients' growing demand for shorter incisions, and whether the less-invasive approach will ever totally take the place of traditional knee replacement surgery.
"Minimally invasive surgery (MIS) is no longer just about making smaller incisions," said Robert E. Booth, Jr., MD, chief of orthopaedic surgery at Pennsylvania Hospital in Philadelphia. "The procedure now includes a range of precise techniques to control pain, get people back on their feet and back to work more quickly."
Less-invasive knee replacement surgery involves an incision of three to four inches as opposed to the eight- to 10-inch incision required for traditional surgery. Surgeons attempt to reach the knee without cutting into tendons, muscles and other tissues around the knee.
Minimizing pain in the days and weeks after surgery is a primary goal of the procedure. Patients are given anti-inflammatory medicine and local anesthesia before surgery, and pain medications after the operation. Patients also receive counseling about what to expect from the surgery, the length of the recovery process and how much pain they may experience.
"Often times if you tell patients beforehand that taking medication will reduce their discomfort, they will, indeed, feel less pain," Dr. Booth explained.
Like the traditional surgery, the less-invasive approach has many of the same risks like infection and blood clots. But smaller incisions mean surgeons have to operate in a more compact area with a reduced field of vision.
"Any time surgery is performed with a smaller incision, the surgeon has fewer visual clues to guide them on techniques, such as the appropriate placement of the implant," said Mark W. Pagnano, MD, associate professor of orthopedics at the Mayo Clinic College of Medicine in Rochester, Minn. "Particular care must be taken during surgery not to damage tissue around the knee."
Computer-assisted navigation systems make the procedure safer when visibility is compromised. The length of the incision, however, is the least important factor in the successful outcome of the procedure. Smaller incisions necessitate more force on the tissues that may inhibit wound healing.