Articular Cartilage Structure And Function
Comprised of the protein collagen, the knee articular cartilage structure is one of the components of a person’s knee. The articular cartilage is a hard and smooth material and is found on the articulating surface of the bones. The articular cartilage function is to allow the bones in a joint to move without causing excess friction and damage. When this cartilage has become damaged, the bones can grind against each other instead of having fluid movement. Because the cartilage receives no direct blood supply, injuries can be serious and take an extended period to time for recovery.
While articular cartilage is present in many different areas of the body, that of the knee is the most common to receive injuries. The reduction of friction between bones is extremely important and is necessary to maintain a body’s mobility. Despite its relative smallness, the cartilage has four distinct zones. The calcified area has been partly mineralized and is where the cartilage meets the subchondral bone. The deep area is characterized by perpendicular-running collagen fibrils and has columns of chondorcytes around the fibrils’ axis. The middle area is mainly comprised of collagen and round chondrocytes. The last area, superficial, has low quantities of proteoglycan and high amounts of collagen fibrils that run in a parallel direction to the cartilage’s surface
Injuries to the articular cartilage can happen as an isolated issue or in combination with other problems. In many cases, damage to the cartilage is accompanied with anterior cruciate ligament injuries. Sometimes, the erosion of the articular cartilage is simply a case of wear and tear. As the ACL’s responsibility is to inhibit excessive knee rotation, an ACL tear can easily result in damage to the tibia and femur’s articular cartilage. The damage is graded from level 1, which is characterized by inflammation and pain that is not detectable with an arthroscopy, to level 4, which clearly exhibits bone damage. The articular cartilage damage is associated with symptoms including chronic pain, knee swelling, audible clicking sound during knee motion, and locking of the knee. Untreated cases of cartilage damage can be a precursor to arthritis in patients.
Treatment is available to patients who have suffered articular cartilage function damage. In some cases, simply using the RICE technique is enough to reduce the symptoms. In other more serious cases, medical intervention may be needed. This surgery will attempt to either reattach the articular cartilage or reconstruct it depending on the level of damage. The different types of surgery are as follows: microfracture, abrasion arthroplasty, drilling, autologous chondrocyte implantation, and osteochondral autograft or allograft transplantation. The most severe patients will require articular cartilage repair surgery which can include bone marrow stem cell transplants to speed up the recovery time. Research efforts are currently looking for improved treatment as more detail is learned about how the knee functions. The knee articular cartilage structure is resilient in nature, but recovery from damages to this area of the body can be lengthy and debilitating.