A torn ACL (anterior cruciate ligament) is a painful and potentially debilitating condition. ACL tears are very common. Each year in the United States, between 100,000 to 200,000 people tear their ACL. The ACL cannot heal on its own. Once torn, it will stay torn unless surgery is performed.
For some patients – mainly older people and others whose lifestyles do not include running or other rigorous excercise – conservative, nonsurgical treatments may allow them to successfully return to their normal routines.
However, anyone who has torn their ACL and returns to unrestricted activity without an intact ACL will likely experience some knee instability. Most people with active lifestyles, especially those who participate in competitive sports or other rigorous athletic activities, will need surgery to return to their prior level of activity and avoid future injury.
Without an intact ACL, a person is also much more likely to tear their meniscus. The meniscus is a pad of cartilage that cushions the bones that meet at the knee joint. There are two menisci on each knee: the medial meniscus on the inside of the knee and the lateral meniscus on the outside. A torn meniscus will cause knee pain and, sometimes swelling. More importantly, however, a damaged meniscus increases a patient's risk of developing osteoarthritis of the knee later in life.
Most people with active lifestyles, especially those who engage in competitive sports, will need ACL surgery in order to reduce the risk of future injury.
In most cases, it is not possible to surgically repair or reattach a torn ACL. Most often, ACL surgery involves a complete rebuilding of the ACL. This procedure, called ACL reconstruction, is the current standard of care for surgically treating tears of the ACL.
The surgeons at the HSS Sports Medicine Institute have drafted guidelines for people who are considering ACL treatment.
In ACL reconstruction surgery, a new ACL is made from a graft of replacement tissue from one of two sources:
The type of graft used for each patient is determined on a case-by-case basis.
ACL reconstruction surgery is performed using minimally invasive arthroscopic techniques, in which a combination of fiber optics, small incisions and small instruments are used. A somewhat larger incision is needed, however, to obtain the tissue graft. ACL reconstruction is an outpatient (ambulatory) procedure, in which patients can go home on the same day as their surgery.
At HSS, most patients who undergo ACL reconstruction are given an epidural nerve block during their surgery, rather than being placed fully unconscious under general anesthesia. This epidural is the same type of regional anesthesia many women receive during childbirth.
Reconstruction of the ACL follows a number of basic steps, although they may vary slightly from case to case:
Below, view an animation for a more detailed description of a minimally invasive ACL reconstruction.
ACL reconstruction is generally scheduled for between three and six weeks after the injury occurs. This allows inflammation in the area to subside. If surgery is performed too early, patients may develop a profound scarring response called arthrofibrosis.
Orthopedic surgeons gauge the appropriate timing of surgery based on:
It usually takes six to nine months for a patient to return to participating in sports after an ACL reconstruction, depending on the level of competition and the type of activity.
Patients are able to walk with crutches and a leg brace on the day of surgery. Very soon after surgery, the patient enters a rehabilitation program to restore strength, stability and range of motion to the knee. The rehabilitation process is composed of a progression of exercises:
The degree of pain associated with ACL recovery varies and can be addressed successfully with medication. Recovery time also varies from patient to patient. The determination of when a patient has fully recovered is based on the restoration of muscle strength, range of motion and proprioception of the knee joint.
Arthroscopic surgical techniques have made recovery times quicker and easier, compared to when ACL construction was conducted through open surgery. But to achieve a successful outcome, it is critical to have the rehabilitation period carefully supervised by an appropriate physical therapist and to have follow-up appointments with the surgeon.
Below, explore articles, blogs and other content on ACL injuries or select Treating Physicians to find the best doctor or surgeon at HSS to suit your specific condition and insurance.
In this video, a high school student and premier club soccer player from Fairfield County, Connecticut, discusses tearing her ACL and her journey back to competitive sports with clinicians at HSS Stamford.
Read detailed content on treatments for ACL tears.
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