What Is an ACL Injury?
Byline: Jose Pujalte, Jr. M.D.
He has no resolution, he shrinks from pain or labor in any of its shapes. His very attitude bespeaks this: he never straightens his knee joints, he stoops with his fat ill-shapen shoulders, and in walking he does not tread but shovel and slide.
Thomas Carlyle (1795-1881), Scottish essayist and historian. Letter, 24 June 1824, to his brother, following Carlyle's first encounter with Coleridge (published in Collected Letters, vol. 3).
YOU'VE heard it or read it somewhere, the ACL. Most likely, some knowledgeable sportscaster mentioned that Mr. PBA or NBA hotshot has been sidelined for the season because of his busted ACL. The ACL stands for "anterior cruciate ligament." It is what keeps your main leg bone (the tibia) from slipping forward past your thigh bone (the femur). Think of your knee as one big hinge. For this hinge to move smoothly, thick and strong cords forming a cross (Latin crux), the cruciates alternately tighten on each other and untwist, coupling the bone ends. Without cruciates, you'd walk like a stop-motion clay figure straight out of Nickelodeon, in pain.
Who is at risk? You don't have to be an athlete to get an ACL injury. However, it is common in basketball, soccer, volleyball, and in the martial arts. In the US, it is called the "skier's knee." I've heard that sports medicine doctors are doing brisk business at the slopes of Vail and Aspen (!). Whatever the sport or activity, the specific mechanism calls for the foot to be firmly planted followed by a sudden twisting motion of the knee outwards. A strong blow on the side of the knee can also damage the ACL. In high impact vehicular accidents, the ACL and other ligamentous structures may be involved.
Signs and Symptoms. Classically, at the exact moment of ACL damage, you'll hear a "pop" in the knee. Onomatopoeia aside, there can be a sensation of ripping followed by immediate pain, swelling, redness and an overpowering need to put your arm around someone (because you need help standing up).
If you choose to ignore the physical insult and merely rest the knee, I have bad news. The ACL does not heal. If it's been torn, it will stay torn. That is why in neglected cases, there is the next classic sign of ACL injury - the knee suddenly giving way in an attempt to walk. In a chronic condition, there is a distinct sensation of an unstable knee. That's your bum knee right there, in protest. Depending on how much you continue using the knee, there will be recurring episodes of stiffness and inflammation.
Diagnosis. The bone and joint surgical specialist, the orthopedic surgeon, is the doctor to see. While the knee is particularly strong and resilient, once the ligaments are out, it becomes unwieldy. …