If you follow or play sports, you’ve likely seen a player on your favorite team injure their ACL, had one of your own teammates injure their ACL, or maybe you’ve even torn your own. As an athlete or sports fan, we know that an ACL injury usually means surgery, an extensive rehabilitation and a significant loss of playing time. However, most athletes or sports fans aren’t as familiar with some of the details of what the ACL is or the specifics of what happens after you tear your ACL.
What is the ACL?
The ACL — or anterior cruciate ligament — is the main stabilizing ligament in the knee. The ACL connects the femur (thighbone) to the tibia (shinbone). It prevents the tibia (shinbone) from moving forward when we stop quickly, pivot, cut or land from a jump. It also provides some rotational stability preventing the tibia from rotating during those maneuvers.
Understanding ACL Injuries
ACL injuries can occur from direct contact such as getting hit on the side of your knee. However, it is more common to experience a noncontact injury which often occur with explosive movements, such as:
– Landing from a jump.
– Slowing down or stopping suddenly.
– Changing direction or cutting quickly.
– Hyperextending your knee.
The sports that rely heavily on those aforementioned movements are the sports with the highest risk of ACL injuries: soccer, football, basketball, lacrosse etc. Most often, athletes will experience an audible pop with injury and feel as though their knee “gave out.” The pop is the ACL tearing, and the knee giving out is the tibia (shinbone) shifting forward and rotating as the stability from the ACL is lost.
These injuries often result in pain, pretty significant swelling, and instability in the knee. Athletes should seek immediate evaluation and treatment for suspected ACL injuries. The first line of the Sports Medicine team is often the athletic trainer who will be able to assess the injury on the field or sideline and start initial treatment with ice and stabilization. The next step is scheduling an appointment as soon as possible with a sports medicine orthopaedic specialist.
Diagnosis and Treatment
A sports medicine specialist can often diagnose an ACL injury with a physical exam, comparing the injured knee to the uninjured one. However, even if the physical exam is consistent with an ACL tear, an MRI (magnetic resonance imaging) scan will be ordered to help confirm the diagnosis of ACL tear, but also to look for other injuries in the knee that often occur with an ACL tear. The most common injuries associated with an ACL tear are injuries to the meniscus, other ligaments or cartilage.
– Meniscus: You have two menisci in each knee. They are “C-shaped” shock absorbers that sit in between the femur (thighbone) and tibia (shinbone) and help protect the cartilage in your knee.
– Ligaments: Besides your ACL, the other main ligaments in the knee are the PCL (posterior cruciate ligament), MCL (medial collateral ligament) and LCL (lateral collateral ligament). The most common ligament to be injured at the same time as an ACL is the MCL. This may or may not need to be addressed with surgery depending on the location of the injury to the ligament and the severity. A sports medicine orthopaedic surgeon will be able to assess those factors through the MRI images and by examining your knee. It’s important to ensure — whether through surgery or bracing – that any additional ligament injury heals to restore stability to your knee.
– Cartilage: This is the smooth, shiny surface on the end of the femur (thighbone) and tibia (shinbone) that allows the bones to move smoothly across each other as your knee bends and straightens. When your cartilage degenerates, the motion becomes less smooth, and the knee becomes painful — this is called arthritis. The goal in treating ACL and meniscus injuries is to protect your cartilage and prevent or delay degeneration.
Treatment of an ACL tear depends on the level of activity you wish to return to. If you want to return to activities that require explosive movements like cutting, jumping, pivoting, accelerating, or decelerating, you will need surgery to restore stability to your knee. In order to restore ACL stability to your knee a surgery called ACL reconstruction will need to be performed. This is where a part of a tendon from somewhere else in your body called a “graft” (patella tendon, quadriceps tendon or hamstring tendon) is taken and placed inside the knee to become your new ACL. At the time of ACL surgery, any other possible injuries to the meniscus, cartilage or additional ligaments are addressed surgically if needed.
Return to Play
Returning to full participation in your sport after ACL reconstruction surgery typically takes somewhere between seven to nine months. As a sports medicine surgeon, I want to get you back to play as quickly and safely as possible. There are two main requirements to return to sport safely after ACL reconstruction. First, we have to wait for the surgically reconstructed ACL to heal, allowing it to withstand the forces placed on it during sports. Second, in the first month or two after ACL surgery, you lose a substantial amount of muscle in your injured leg, and it takes significant time and effort to regain that muscle strength and conditioning. If you go back to sports before you fully regain that strength and conditioning, you are at risk for re-injuring the same ACL or suffering another major injury. This rehabilitation process is guided by your physical therapist and athletic trainer if you have one. Like most sports, sports medicine requires a team approach. Your surgeon, physical therapist, and athletic trainer will all work closely together throughout your recovery process. When enough time has passed for your new ACL to heal and you have regained full strength and conditioning in that leg, you will be cleared to return to sport and get back to doing the things you love.
by John M. Kunkel, D.O.
UPMC Orthopaedic Care
John Kunkel, D.O., is a sports medicine orthopaedic surgeon with UPMC Orthopaedic Care and sees patients at 1201 Grampian Blvd., Williamsport. He currently serves as the medical director for the Little League World Series, the head team physician for Lycoming College Athletics, and is a consulting orthopaedic surgeon for the Williamsport Crosscutters (MLB Draft League). He has worked with the Houston Astros (MLB), Houston Texans (NFL), and NASA Astronaut Corps. For more information about UPMC Orthopaedic Care and sports medicine services in north central Pa., visit UPMC.com/OrthoNCPA or call 570-321-2020.
