w w w . s t h e l e n a h o s p i t a l c l e a r l a k e . o r g | 9
Cartilage repair and regeneration is treatment for an otherwise
healthy knee, but not for knees affected by osteoarthritis, a
condition that causes natural cartilage deterioration from aging.
Who is eligible?
The treatment is recommended for patients with knee cartilage
damage or deterioration caused by:
■
Injury or trauma, including sports injuries.
■
Repetitive use of the joint.
■
Congenital abnormalities, meaning those that a
person is born with, affecting normal joint structure.
■
Hormonal disorders that affect bone and
joint development, such as osteochondritis
dissecans (OCD).
Microfracture/drilling.
The goal of microfracture is to
stimulate the growth of new articular cartilage by creating a new
blood supply. A sharp tool, called an awl, or a high-speed drill is
used to make multiple holes in the joint's surface. The holes are
made in the bone beneath the cartilage, called subchondral bone.
This action creates a healing response. A new blood supply can
reach the joint surface, bringing with it new cells that will form
the new cartilage.
Abrasion arthroplasty.
Abrasion arthroplasty is similar to
drilling. Instead of drills or wires, high-speed burrs are used to
remove the damaged cartilage and reach the subchondral bone.
Autologous chondrocyte implantation (ACI).
ACI is a two-step procedure. New cartilage cells are grown
and then implanted.
First, an arthroscopic surgery is performed and a small amount of
healthy cartilage tissue is harvested. The tissue, which contains
healthy cartilage cells, or chondrocytes, is then sent to the
laboratory. The cells are cultured and increased in number over
a three to five week period.
A surgical procedure, or arthrotomy, is then performed
to implant the newly grown cells.
ACI is most useful for younger patients who have single defects
larger than 2 centimeters in diameter. ACI has the advantage
of using the patient’s own cells; however, it does have the
disadvantage of being a two-stage procedure.
Types of Cartilage Restoration Procedures
Osteochondral autograft transplantation.
In this
procedure, cartilage is transferred from one part of the joint to
another. Healthy cartilage tissue — a graft — is taken from an
area of the bone that does not carry weight (non-weight-bearing).
The graft is then matched to the surface area of the defect and
then impacted into place. This leaves a smooth cartilage surface
in the joint.
Osteochondral allograft transplantation.
If a cartilage defect is too large for an autograft, an allograft may
be considered. An allograft is a tissue graft taken from a deceased
donor. Like an autograft, it is a block of cartilage and bone. In the
laboratory, it is sterilized, prepared and tested.
These are just a few of many techniques available today. There is
vast research being done on new techniques which will continue to
change the way we think and treat cartilage injuries.
Once upon a time, people with joint pain
resulting from cartilage damage just had to grin
and bear it. Today, advances in research and
technology have made the repair, regeneration,
and replacement of cartilage possible for
athletes and others with debilitating joint
cartilage damage…sometimes with such
success that there is no need to use artificial
joints to restore mobility.
To learn more about
new advances in cartilage
restoration, contact
Brian Freeto, MD,
at 707.995.4508.
Brian Freeto, MD