Approximately 15 million people in the United States suffer from severe osteoarthritis of the knee. Many of these people have arthritis severe enough to prevent full participation in what would be an otherwise active lifestyle. Some people give up sports, others give up walking even a few blocks at a time.
The three compartments of the knee.
When arthritis becomes severe, pain can be intolerable. Eventually, activity limitation becomes unacceptable, so many people pursue total knee replacement. Total knee replacement has been the gold standard for surgical treatment of knee arthritis, and up to 500,000 knee replacements are performed each year in the United States.
Total knee replacement is a successful surgical procedure, but it replaces the entire joint, even when parts of joint remain healthy. The knee joint consists of three compartments: the medial compartment, the lateral compartment, and the patellofemoral compartment. It is estimated that up to 25-30% of patients with severe knee arthritis actually have arthritis limited to one or two of these compartments.
Frequently, arthritis is limited to the medial compartment, only. In other cases, arthritis may be limited to the patellofemoral or lateral compartments. Many patients have arthritis limited to the medial and patellofemoral comapartments, while the lateral compartment is preserved. For all of these patients, a total knee replacement would require removal of healthy tissue.
Partial knee resurfacing focuses on arthritic tissue, and leaves healthy cartilage and ligaments in place. Unlike total knee replacement, partial knee resurfacing does not sacrifice the anterior or posterior cruciate ligaments. Preservation of normal anatomy allows for a knee that functions and feels more like a normal knee.
Compared to patients undergoing total knee replacement, patients treated with partial knee resurfacing experience less postoperative pain, and they experience an earlier postoperative recovery. Some patients leave the hospital on the day of surgery, and many have resumed an active lifestyle within four to six weeks.
MAKOplasty® Robotic Arm Assisted Partial Knee Resurfacing
MAKOplasty® represents the latest advance in partial knee resurfacing. This technology is the logical extension of computer navigation in knee replacement, and it allows for greater precision and reliability.
The success of a uni- or bicompartmental arthroplasty depends on the accurate placement of components. Previously, this was based on anatomic landmarks noted at the time of surgery. This process is subject to surgeon error, and variations in component placement have been observed on postoperative x-rays. The degree of difficulty increases as the size of the surgical incision decreases and anatomic landmarks become more difficult to discern.
Traditional unicomparmental knee arthroplasty requires the use of a hand-held power saw and cutting blocks secured to the bone. The cutting blocks require significant dissection, and the hand-held saw is subject to displacement during use.
MAKOplasty® solves a number of problems inherent in traditional unicompartmental knee resurfacing. Optimum component placement is assured with the use of computer navigation, coupled with a preoperative computerized model based on a CAT scan. The appropriate size and position of components are determined preoperatively, not during surgery. At the time of surgery, based on computer navigation coordinates, the alignment and position of the components can be adjusted, and appropriate soft tissue balance can be assured before any bony cuts are made.
Instead of a hand-held saw and cutting blocks, with MAKOplasty® a surgeon interactive robotic arm that combines virtual three-dimensional imaging with an intelligent bone sculpting tool is utilized. While the surgeon controls the robotic arm, it prevents any cut from extending beyond the boundaries determined by the preoperative template. This provides greater precision and allows for the surgery to be performed through smaller incisions.
With the potential for greater precision and decreased dissection, MAKOplasty® offers a considerable benefit for patients requiring a partial knee resurfacing.
Dr. Hammerberg has performed the first MAKOplasty® surgeries in Colorado, and he is the only surgeon in Colorado currently trained to provide this technology. It is only available at the Bone and Joint Institute at Exempla Good Samaritan Medical Center.
Frequently, arthritis is limited to the medial compartment, only. In other cases, arthritis may be limited to the patellofemoral or lateral compartments. Many patients have arthritis limited to the medial and patellofemoral comapartments, while the lateral compartment is preserved. For all of these patients, a total knee replacement would require removal of healthy tissue.
Instead of a hand-held saw and cutting blocks, with MAKOplasty® a surgeon interactive robotic arm that combines virtual three-dimensional imaging with an intelligent bone sculpting tool is utilized. While the surgeon controls the robotic arm, it prevents any cut from extending beyond the boundaries determined by the preoperative template. This provides greater precision and allows for the surgery to be performed through smaller incisions.
