The anterior cruciate ligament is one of four primary ligaments around the knee joint. It is an important stabilizer of the knee. The ACL can be injured by trauma or sporting activities. If the ligament is completely torn, it will not heal. Some individuals elect to leave the knee without an anterior cruciate ligament, and some choose ACL reconstruction of the ligament. If the knee has a deficient anterior cruciate ligament, the individual relies on the other three ligaments (as well as the inherent stability of the joint and surrounding muscles) to stabilize the joint. This is not always sufficient, and may lead to recurrent episodes of instability--a sensation that the knee may "give out." For more information on the anterior cruciate ligament:
Understand ACL Injuries
Do I Need ACL Surgery?
- Allows return to high-level athletic activity
- May protect future damage to the knee cartilage
- Offers a near-normal knee
- Surgery is not 100% effective -- some people don't improve
- Many activities can be accomplished without an ACL
- There are complications that may occur
ACL reconstruction surgery should be considered for all individuals who desire a return to sports or activities that require lateral pivoting of the knee, or those who experience recurrent instability of the knee.
Who needs ACL surgery?
- Most people expecting to return to high-level athletic activities in sports such as soccer or basketball
- Individuals who experience recurrent episodes of knee instability due to anterior cruciate ligament deficiency
- Patients who do not want to attempt conservative therapy
What is an ACL reconstruction?
Although people (including doctors) often refer to the surgery as an "ACL repair," it is better called an "ACL reconstruction." The anterior cruciate ligament, once completely torn, cannot be repaired. The options for ACL reconstruction are:
- Using the central 1/3 of the patellar tendon, the tendon connecting the knee cap (patella) to the shin bone (tibia), to fashion a new ligament. When the graft is 'harvested,' a piece of the bone of the patella and tibia is also taken. Thus the attachments of the tendon to the bone are not disturbed. When the graft is placed into the knee, this allows for 'bone to bone healing.' This is felt by many surgeons to be the most secure graft type. The primary disadvantage is knee pain following the surgery; this may persist for years.
- Using a portion of the hamstring tendon. The hamstring muscle group (in the back of the thigh) has tendon to spare. Some of the tendon can be harvested to create a graft. The advantage of the hamstring tendon is that there is less disturbance in harvesting the graft, and a much lower incidence of knee pain after surgery. However, many surgeons question the stability of this graft.
- Finally, many patients now opt for donor tissue grafts. These usually use the patellar tendon of a cadaver, similar to using your own as described above. The problem with this is the sterilization process that kills the living cells of the graft. This means the healing time of the graft is longer and less reliable. There is a very small risk of infection, as is the case with any donor tissue. The advantage is that this procedure can be done entirely arthroscopically, and there is much less post-operative pain.