Can you name a key component of the knee that stabilizes the joint?
Actually, the knee has 4 main ligaments. The anterior cruciate ligament (ACL) is most well-known, because it is frequently torn. Its counterpart is the posterior cruciate ligament (PCL). Both these ligaments are located in the center of the knee and control the tibia (shin bone), with the ACL in the front of the knee and the PCL in the back. The ACL controls the forward movement of the tibia, while the PCL controls backward movement of the tibia. The ACL also controls the rotation of the knee, which is important when making agile movements like pivoting and changing direction. If the ACL is torn, the knee can dislocate and collapse uncontrollably, producing the sensation of “giving way.”
The other two ligaments are key to providing stability. The first one is the medial collateral ligament (MCL), which is located on the inner side of the knee. The second one is the lateral collateral ligament (LCL), which is located on the outer side of the knee. These ligaments help in situations like walking along uneven roadsides. If these ligaments are weak, walking is difficult and falling over may occur easily.
Have you heard of the meniscus? What is it, and why is it important?
The meniscus is a lot like a pillow. Just like your pillow is a cushion between your head and bed, the meniscus is a set of two pieces of cartilage that act like a cushion, or shock absorber, between your shinbone (tibia) and thighbone (femur). Each piece of cartilage is C-shaped with a wedge-shaped cross-section. One piece is on the outer part of the knee (lateral meniscus), and one piece is on the inner part of the knee (medial meniscus). The shape of the meniscus allows it to conform to the bones and fill the gap between them while helping to evenly distribute body weight across the joint.
Our body has many parts that work in harmony, usually without any problem. For example, even though the tongue is always close to the teeth, it rarely gets bitten. From time to time, however, we accidentally bite our tongue. It’s the same way with the meniscus. Despite being squashed between two large bones, it doesn’t usually become injured. However, any activity that causes you to forcefully twist or rotate your knee, such as aggressive pivoting or sudden stops and turns, can accidentally cause the meniscus to tear. Sports-related meniscus injuries often occur along with other knee injuries, such as anterior cruciate ligament (ACL) tears.
What does a normal healthy knee feel like?
A normal healthy knee will have three qualities. First, you won’t notice your knee is there. Second, it will be stable. Third, it will be fully functional and able to move freely. What that means is that the knee doesn’t experience anything noticeable, such as pain, crunching/popping sounds, swelling, or tightness. People with normal healthy knees never think about them. However, if your knee is bothering you, you might be interested in how a knee can both be stable and able to freely move, because this seems like a contradiction. The truth is, the knee is a miracle of nature, created to perfectly fit together so that we can stand firmly while also giving us the freedom to move through life. That’s why solving knee problems is a challenge. A small mistake in treatment can result in damage. For example, consider repairing the ACL. If the ligament is improperly placed during the repair, the ligament will end up pulling on itself. Eventually, the tension will cause the tendon to become stretched, loose, and ultimately unstable. It’s much like a door that has improperly aligned hinges and you can’t open and close the door properly. The improper alignment requires excessive force to open it, which can cause damage to the hinges or other parts of the door.
