What is an ACL?
ACL stands for “anterior cruciate ligament.” In the knee, a ligament is tissue that connects two bones (holding the shinbone and thigh bone together). It is one of two ligaments that cross within the center of the knee. The ACL’s primary role is to stabilize the knee in front to back (anterior) and rotational movements — preventing excessive forward movement and limiting rotational knee movement.
How does an ACL injury occur?
ACL injuries occur when the stress applied to the connective tissue (ligament) exceeds the strength of it. ACL injuries can occur from contact or noncontact injuries. Contact injuries often occur when a force is applied to the outside of the knee. Many noncontact injuries occur with dynamic twisting movements of the knee that occur in sports, particularly when wearing cleats. An ACL injury can occur when your foot is firmly planted and a sudden force hits your knee, while your leg is straight or slightly bent. It can also be caused by sudden pivoting/turning during sports.
ACL injuries, especially noncontact injuries, are more common in women. While there are many hypotheses attempting to explain this discrepancy, one of the prevailing theories relates to the body dynamics when landing from a jump that we see more commonly in female athletes.
The vast majority of ACL injuries are complete tears. Because the ACL is comprised of two discreet bundles of connective tissues (ligaments), it is possible to experience a partial tear, which often involves damage to only one bundle of the ACL.
How can I prevent ACL injuries?
Many ACL prevention programs are used to try to minimize the risk of an ACL injury. As many noncontact ACL injuries occur when landing from a jump, many of these programs focus on improving the athlete’s jumping mechanics. Strengthening the muscles on the back of the thigh (hamstrings) can also help prevent ACL injury from over-dominance of the muscles on the front of the thigh (quadriceps) muscle group.
Can you repair an ACL without surgery?
The ACL does not have the ability to heal itself. Therefore, the prevailing thought is that once the ACL is injured, it will always be injured. There are studies looking at use of orthobiologics, such as platelet-rich plasma, to help heal ACL injuries; however, the results of these studies have had conflicting results to date.
While ACL reconstruction is generally recommended for most active patients who wish to return to an active lifestyle, strengthening the hamstrings will help to compensate for the loss of function of the ACL for patients who are either not candidates for surgery or who chose to pursue non-operative treatment.
What is arthroscopy surgery?
Arthroscopic surgery is minimally invasive surgery that utilizes smaller incisions with a shorter recovery time. Through a small incision using a high-definition camera about the size of a metal drinking straw, the surgeon can see inside and around the joint on a monitor within the operating room. The other small incisions are used for the instruments that help the surgeon perform the surgery. Very complex procedures can be performed arthroscopically, which often allow quicker and easier recovery compared to traditional open procedures.
What is the most important goal after ACL surgery?
Goals after ACL surgery depend on the stage of recovery. The primary goals of the initial post-operative phase is to regain full motion of the knee, decrease the expected swelling that occurs immediately following ACL reconstruction, and begin strengthening the front of the thigh muscle. As the patient progresses through his or her recovery, the focus will transition to regaining full quadriceps strength, improving body mechanics and returning to sport activities for patients who wish to return to athletic participation.
What types of treatments are there for ACL injury?
Nonoperative and operative treatment are the two types of treatment for ACL injuries. Generally, operative treatment is recommended for patients with little or no osteoarthritis who wish to return to an active lifestyle. Nonoperative treatment is primarily reserved for patients with more advanced osteoarthritis or lower activity levels.
Nonoperative treatment can consist of a variety of modalities including bracing and physical therapy. Physical therapy will focus on strengthening muscles that perform a similar function to the ACL to compensate for the deficient ACL.
Operative treatment consists primarily of surgical reconstruction of the ACL. This can be done using either a donor graft (allograft) or the patient’s own tissue (autograft). In rare instances, the patient’s ACL may be able to be repaired rather than reconstructed or replaced.
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