Minimally Invasive Knee Replacement

Traditional knee replacement procedures typically require a 10-inch incision. The associated discomfort, along with a gradual recovery process, may make some patients reluctant to seek surgical treatment.

Thanks to advances in surgical techniques and instruments, knee replacement is no longer just traditional.

Two newer procedures — minimally invasive total knee replacement and partial knee replacement — now offer many arthritis patients both the advantages of joint surgery and the benefits of a smaller incision.

According to D. Kelly Agnew, M.D., an orthopedic surgeon with Tri Rivers Surgical Associates, this can mean less pain, a shorter hospital stay, accelerated physical therapy, better joint motion and a faster return to activity.

"Joint replacement is the only treatment that can provide permanent relief from arthritis pain," Dr. Agnew said. "Patients tend to be very happy with the long-term results, but there’s a period following surgery when recovery can be uncomfortable, slow and challenging. Using minimally invasive techniques, we can replace an arthritic knee through a four- to five-inch incision, allowing the patient to heal more quickly."

Minimally invasive total knee replacement has the same goal as traditional total knee replacement — to remove the damaged joint and replace it with a prosthetic joint made of materials such as ceramic, metal and plastic. Because a smaller incision is used, surrounding tissue is spared.

Partial knee replacement — also called unicompartmental knee replacement — differs from standard knee replacement surgery because only a portion of the knee, rather than the total joint is replaced. This is another tissue-sparing approach.

"The knee is comprised of three joint compartments - medial, lateral and patellofemoral — that can be affected by osteoarthritis," Dr. Agnew. "Patients with early-stage arthritis that is primarily confined to the inside, or medial, compartment may qualify for partial knee replacement surgery."

During partial knee replacement surgery, the surgeon uses minimally invasive techniques to remove diseased cartilage and bone only from the medial compartment and replace it with a metal and plastic implant. The rest of the knee is left intact.

"Following knee replacement surgery, patients typically experience dramatic reduction in pain and stiffness and often find they can do things they haven’t done in years," Dr. Agnew said.

David, 61, agrees.

An active grandfather, the Butler resident delayed knee replacement surgery for two years, even though osteoarthritis caused chronic knee pain, stiffness and loss of mobility. When his Tri Rivers Surgical physician suggested minimally invasive total joint replacement, David decided to move ahead with treatment. His physician, Thomas S. Muzzonigro, M.D., was able to replace David’s damaged knee through an incision shorter in length than a ballpoint pen.

After surgery, David experienced much less pain than he expected and was able to return to some normal activities weeks earlier than he hoped. With his recovery progressing quickly, David takes comfortable walks with his wife on cool evenings and enthusiastically recommends minimally invasive total knee replacement to other people.

"Don’t wait," he tells others considering the procedure. "You’re losing precious time that could be spent doing the things you enjoy."

A patient interested in learning if he is a candidate for minimally invasive knee replacement should consult a board-certified orthopedic specialist trained and experienced in performing these procedures. After careful examination of the affected knee, the physician will recommend surgery and discuss the benefits and potential risks associated with each technique.

"Patients tend to do very well after minimally invasive joint replacement surgery," Dr. Agnew said. "We use this approach whenever possible."

Joint replacement is typically considered when non-surgical treatments such as medication, injections and physical therapy can no longer control arthritis symptoms, Dr. Agnew said. More than 90 percent of patients who receive a joint replacement report a high level of satisfaction with the outcome.

With minimally invasive options now available, knee arthritis patients may find that the gain comes with less pain.