Bone-tendon-bone grafts are made from part the knee cap, the
patella tendon, and part of the tibia (shin bone). They are the most
common graft use around the world and have the highest success rate.
They are usually harvested from the same knee that the ACL is torn
from at the time of reconstruction. They have the strongest fixation
methods, the best healing rates, the lowest incidence of re-rupture,
and produce the most stable knee over a lifetime. Because of these
facts it is the graft most commonly used by Dr. Allison.
Hamstring grafts are made by taking the tendons of the hamstring
muscles from the back of the leg in which the ACL is torn at the
time of reconstruction. These have become more popular in the last
few years with the advent of better fixation techniques. They have
the advantage of not taking away any bone and may have less pain
associate with them. They have the disadvantage of having a less
stable knee due to the fact that the tendons may stretch over time,
having a much higher re-rupture rate, and having a higher revision
surgery rate. Two separate studies in the Journal of Sports Medicine
have recommended that these grafts only be used on a limited bases
on low activity patients. Because of these studies Dr. Allison is
only using these grafts on very selective patients.
An allograft is a graft that is taken from a cadaver (a person who
is no longer living). These can be bone-tendon-bone grafts,
hamstring grafts, or even from part of the heel and a part of the
Achilles tendon. Although they are extensively tested there is still
a small chance that disease could be spread through these grafts.
Their healing rates are lower and there is a higher re-rupture rate
and re-operation. Dr. Allison only uses these grafts on patients who
have had multiple surgeries and have no other alternative.
Some artificial materials have been used to try to reconstruct the
ACL without taking a graft from the patient or placing a graft from
another person. The most widely used of these was the Dacron graft.
These artificial grafts caused a reaction within the knee and had to
be abandoned. There are currently no artificial grafts that work
well or considered reasonable for ACL reconstruction at this time.
REPAIR WITHOUT A GRAFT
When ACL surgery first began, the knee would simply be opened and
the ACL sutured back together. It was found that the ACL would not
heal and the sutures would finally pull through. These knees would
have to go through a revision surgery to reconstruct the ACL using a
graft. Direct repair of the ACL by suturing is not considered a
standard of care at this time.