When cartilage in the knee is damaged, it doesn’t regenerate and causes terrible pain because the raw bone no longer has a flexible cushion. Instead of replacing the joint, surgeons may have the option of replacing the cartilage.
“Well you have to understand that the articular cartilage doesn’t really grow at all. So the number of cells you’re born with is the number of cells you’ll have unless you lose some,” says Dr. John Kagan, orthopedic surgen on Lee Memorial Health System’s medical staff.
Particularly in younger patients with an injury rather than widespread arthritis, doctors are able to transplant cartilage from a donor site.
“We take the bone and cartilage from a non-weight baring, none contact area and move it to a part that is weight bearing. I’ve even taken cartilage from another knee and moved it to an area in the ankle where the cartilage is absent,” says Dr. Kagan.
The transplant is an outpatient procedure. Simply put, the surgeon takes a plug of cartilage and packs the hole. Using an arthroscopic approach, it’s done through small incisions.
“Let’s say you take a 9 or 10 mm diameter core, you make a corresponding opening in the site that’s going to receive it. You’ll actually oversize the donor sight so you force that bone and cartilage to fit in. When you do that, it stays exactly plugged in. You don’t want it sticking up and you don’t want it hanging down,” says Dr. Kagan.
The patient goes home same day, but has to avoid putting weight on the joint for about six weeks. It takes that long for the transplant to integrate in the new location.
“Underneath that articular cartilage is bone and that bone will actually grow in and become a solid part,” says Dr. Kagan.By fixing damaged cartilage, surgeons are often able to repair a patient’s quality of life.