ANTERIOR CRUCIATE LIGAMENT
RECONSTRUCTION
CHOOSING TREATMENT OPTIONS
Seth Rosenzweig, M.D.
SPORTS MEDICINE
CHOOSING TREATMENT FOR AN ACUTE INJURY
TO THE ANTERIOR CRUCIATE LIGAMENT
Injuries to the anterior cruciate ligament (ACL) are very common in
sports. When an ACL is torn, the patient-athlete must decide whether to
let it remain so or to have surgery to repair it. Both choices are
acceptable ones, depending on the particular desires and expectations
of the patient. The purpose of this information is to help you decide
which treatment is best for you.
In most cases, the ACL is completely torn ("ruptured"). Partial tears do
occur and will be discussed later. Usually the diagnosis can be made by
a careful history and physical examination, but occasionally other
studies are necessary to confirm the diagnosis.
When the ACL is completely torn, the ends fall away from each other,
so spontaneous healing is impossible. The unattached ends usually
shrivel up and scar down. The patient has two immediate choices, 1)
have the ligament surgically reconstructed, or 2) trying to live without an
ACL, retaining the option of later reconstructive surgery should the knee
prove unacceptable.
To judge which of these choices is best for you, you must understand
what can happen to people whose ACL has ruptured. In medical jargon,
we call this the Natural History of an ACL tear.
People who have torn their ACLs will fall into three groups:
1) A small, unlucky group will develop a "trick knee" which "gives out"
very easily, even with non-stressful activities such as turning around
suddenly at home. During such a "giving out" episode, the patient feels
the two main bones in his or her leg seem to slip or slide out of place.
These episodes may be painful and are often followed by swelling.
2) Another small, very lucky group is at the other extreme. Individuals in
this group can do virtually anything without trouble. We really don’t know
why an individual may fall into one of these first two groups, but we
suspect that a number of factors may contribute towards making some
knees very dependent on the ACL and other independent on it.
3) The vast majority of people with a torn ACL fall between these two
extremes. They can do all nonstressful daily activities and "straight
ahead" sports such as running, swimming and bicycling without
difficulty, but have some degree of "giving out" when they engage in
activities requiring jumping, pivoting, cutting, or sudden changes of
direction. Some of these people will find that their instability is controlled
adequately by wearing a special brace, while others in this group will
find that their knees give out even while wearing such a brace. The
sports which present the most difficulty are those which require a lot of
jumping or cutting and in which the athlete must react suddenly to
another player (basketball, volleyball, soccer and football are good
examples). Sports in which the athlete may control his or her risk if he or
she is willing to voluntarily moderate his or her participation are less
likely to cause trouble (tennis, racquet ball and skiing are examples of
this type of sport).
In any case, the goal of the chosen treatment is to prevent "giving out"
episodes. Not only are these episodes painful and inconvenient, they
may cause secondary damage to the menisci ("cartilages") and the joint
surfaces and thereby increase the risk of premature arthritis in the knee.
Let us look more closely at the advantages and disadvantages of the
two treatment options.
Option One: Early Surgical Reconstruction of the ACL.
The principal advantage of early surgery is that it provides the best
chance of having normal knee function following an ACL tear. The
surgery has about a 90-95% success rate. In other words, nine out of
ten people who have this operation will not develop "giving out"
episodes or cause further damage to their "cartilages" or joint surfaces.
The primary disadvantage of early surgery is that it exposes the patient
to the risks normally associated with knee surgery including infection,
thromboembolism (blood clots traveling from the leg to the lungs) and
post-operative stiffness. Modern techniques of surgery and rehabilitation
have lowered the chance of these problems, but cannot completely
eliminate these risks.
Option Two: Allowing the Ligament to Remain Torn.
The principal advantage of this option is that the person choosing it
avoids an operation and its associated risks, perhaps forever. The
principal disadvantage is that it may not work, and the patient may end
up with a "trick knee" which requires surgery months or years after the
original injury. These knees may usually be helped with later
reconstructive surgery, but may suffer unrepairable damage to the joint
surfaces or "cartilages" during the period when the knee was unstable.
Which option is better for you?
Ideally, we would like to be able to foretell which patients will develop
"trick knees" and offer them early surgery while discouraging surgery in
the ones who will be able to get along without their ACL. Unfortunately,
there is no way of predicting the future with 100% certainty in every
case. There are, however, guidelines which are very helpful. Patients
who refuse to give up "high risk" sports such as basketball,
volleyball, soccer or football or to moderate their "aggressiveness"
in medium risk sports such as tennis, racquetball, or skiing, will
probably not be satisfied with the results of non-surgical
treatment. Conversely, patients who are willing to give up high risk
sports and moderate their participation in medium-risk sports will often
be satisfied without surgery. Treatment results tend to be age-related,
but only because people’s priorities change with age. For example, a
study from Baylor University showed that 80% of male patients under
age 20 had a major giving out episodes within a year of their initial
injury, while very few patients over 30 had such problems. This is
probably because males younger than 20 generally like to play high risk
sports and usually refuse to moderate their "aggressiveness."
Conversely, people over age 30 have many family and career
obligations and are often willing to moderate their sports participate in
favor low risk sports.
If you are an elite athlete, or younger than 20, it is highly
recommended to undergo reconstruction because of the high risk
of reinjury ("giving way") to the knee. With each reinjury to the
knee, there is an increased risk of damage to the cartilage, which
further increases the risk of developing arthritis.
Making your Choice.
You should, therefore, base your choice upon your own sports priorities.
If you wish to play "high risk" sports at a competitive level, then surgery
is usually the better option for you. If you are a recreational athlete and
are willing to moderate your sports participation, you probably will be
satisfied with the result of non-surgical treatment. Remember, however,
that there is always some chance that you will develop "giving out" even
at reduced activity levels and may later require reconstructive surgery.
Some who choose non-surgical treatment may avoid ligament
reconstruction, but require outpatient arthroscopic surgery because of
associated "cartilage" tears or because the ends of the torn ligament are
interfering with normal knee function.
There are many other factors which may influence your individual
decision. If, after considering the alternatives and discussing them with
me and your loved one, you are still having trouble making a decision,
you probably should choose non-surgical treatment. Some people find a
"second opinion" helpful in coming to a decision. I would be happy to
provide you with a list of orthopedists who are knowledgeable in the
field of knee injuries.
Timing and Techniques
It used to be taught that ACL surgery needed to be done with a "golden
period" of 7-10 days following the injury. That is because early surgery
used to mean suturing back together the shredded ends of the torn
ACL. Since these remnants quickly "shrivel up," surgery had to be done
soon after the injury. The results of this type of surgery have been
shown to be very unreliable, and very few prominent sports medicine
specialist now do it. All sports medicine specialists, myself included,
now replace the ACL with a tendon graft. Because the graft provides the
real strength of the repair and is "harvested" at the time of the surgery,
early ACL surgery may safely be postponed a few weeks or even a few
months if this would be more convenient with the demands of school or
work. The risk of such a delay is small if the patient avoids stressful
activities such as sports or dancing during the "waiting period." Recent
studies show you are most likely to have problems regaining normal
knee motion after the ACL reconstruction if you have surgery too soon
after the ligament injury. Therefore, even if you are certain that you want
to have ligament reconstruction, it is important to wait a few weeks to
regain your motion and allow swelling to resolve prior to surgery.
There are four techniques that are used to reconstruct the anterior
cruciate ligament. The two most common techniques, are to utilize
either a segment of your own patellar tendon, or the hamstring
tendons to reconstruct the anterior cruciate ligament.
The graft is implanted in the knee using arthroscopic techniques. This
technique appears to reduce the chance of scarring within the joint
("adhesion") and consequent stiffness compared to conventional
methods. Skin incisions are still utilized to obtain the tendon graft and to
fix both ends in place.
Some patients may prefer to have an "allograft" reconstruction. In this
case, a similar piece of tendon is transplanted from a "donor" who has
died. Although these tendons are very carefully screened and treated
before use, there is a remote chance (1 : 2,000,000) that a disease,
such as hepatitis or AIDS may be transmitted from the deceased donor
to the patient receiving the transplant. There has never been a case of
this reported in the United States. I will recommend allografts in certain
situations.