Tears of the ACL
The anterior cruciate ligament (ACL) is a major stabilizing knee ligament. It is a tough, non-stretchable rope-like structure that connects the thighbone (femur) to the leg bone (tibia). There are two cruciate ligaments that crisscross in the knee joint. The ACL attaches “anterior” (in front) to the posterior cruciate ligament (PCL). The ACL is more commonly injured than the PCL, and ACL tears more commonly require surgery. Although the surgery is often referred to as an ACL repair it is more appropriately called and ACL reconstruction (see below).
Patients often tear the ACL by changing direction rapidly (e.g. cutting or pivoting), slowing down from running and twisting with one foot planted or hyper-extending the knee when landing from a jump. It is less common to have a direct injury to the knee where another person or object lands on the knee causing the ACL to tear.
Most patients will report hearing a knee pop when their ACL tears. As the tear occurs, the knee usually gives out and fills with fluid and blood. This immediate swelling within first 6 to 12 hours after injury is another hallmark of ACL tears.
The combination of the ACL tear and the swelling causes patients to feel pain. Patients are unable to continue their activity when the injury occurs. Most will limp for several days if not longer.
After a few days the swelling usually decreases and the knee begins to feel better. In some cases people won’t even visit a doctor because they think it is a sprain that is healing. Unfortunately if they try to run, jump or pivot the knee will give-way again causing more injury in some cases. It is important to understand that every patient does not experience each of these symptoms. Some report very little swelling or pain while others cannot straighten or bend their knee for weeks.
Although you may not know that you have torn your ACL, if you do experience a significant knee injury with swelling you should follow the R.I.C.E. program. This treatment includes Rest, Ice, Compression and Elevation (RICE). Swelling occurs because the torn ACL causes bleeding within the knee. The knee joint will slowly absorb the blood and the swelling will usually decrease if RICE is followed.
Less active people may be treated non-surgically with a program of muscle strengthening. However, most healthy, active patients should have surgery to restore full knee function. Three decades ago, patients over age 40 were often told they were too old to have surgery. Unfortunately, there are still some ‘old school’ doctors telling patients the same thing even today. However, as our knowledge and surgical options have improved, we now place no age restrictions on surgery.
Factors such as activity level and lifestyle are much more important than age. It is important to note that if the ACL is not reconstructed, most active patients will experience repeat episodes of their knee ‘giving-way’. Each time this happens, other structures such as cartilage and menisci can be damaged, leading to early arthritis. Since the term ‘active’ can mean many different things to different people, let me define it better. In terms of risk of your knee giving way after the ACL is torn, those people that participate in activities that require twisting, jumping, cutting and pivoting are at greatest risk of further injury.
The next blog will discuss the surgical option in more detail including graft choices, all-arthroscopic surgery and double bundle reconstruction. I was one of the first surgeons in Virginia to perform the all-arthroscopic acl reconstruction procedure and currently also offer the more anatomically correct double bundle acl grafts to patients.
Vic Goradia, MD
Sports Medicine, Knee &
Shoulder Specialist
Go Orthopedics
www.GoOrtho.net
