Dr. Bruce E. Ellison, Orthopaedic Surgeon, discusses ConFormis Bone Sparing Minimally Invasive Knee Replacement

Osteoarthritis of the knee is a degenerative condition affecting millions of Americans. Though often associated with the aging, osteoarthritis involves an overproduction of degradation enzymes which attack and destroyed cartilage.

Healthy joints, including the knee, are covered by a layer of articular cartilage. The cartilage acts as a cushion providing for smooth gliding surface during range of motion. The articular cartilage has no nerves, and thus there is no pain with activity. However as anyone who has broken a bone knows, there are abundant nerves and pain receptors at the bone. In the knee with osteoarthritis, the cartilage wears away and becomes roughened. If the wear becomes significant, the rubbing a one rough bony surface on another can result in debilitating pain, with resulting stiffness and swelling.

Nonoperative treatment options include behavior modification, drug therapies including hyaluronic acid and steroid injections, braces and electrical stimulation. Operative treatments include partial and total knee replacement.

The Conformis iPD is a custom-made minimally invasive "knee replacement" system. It is indicated for patients with mild to moderate osteoarthritis isolated to the medial or lateral compartments of the knee. The device is precisely made based upon MRI [magnetic resonance imaging] of the individual knee.

The device is bone sparing, meaning that no bone is cut or removed from the knee. The surgery is slightly more extensive than a standard knee arthroscopy, and patients leave for home following surgery the same day. Because of device is custom made to match the contours of the knee, it is self seating. There is no need for bone cementing. There is nothing to get loose with time. More importantly, there is to get loose with use.

Unlike a standard knee replacement which requires avoidance of certain sports activities, there are no such restrictions following iPD knee surgery. The procedure takes roughly one hour, involves an incision between one and two inches long, and the patient walks a few hours after surgery with a knee brace, cane, or crutches.

Patients return to regular activities as tolerated, performing exercises for strengthening and endurance.