Ligament tissue is comprised of different grades of collagen, or connective tissue, to connect bone to bone within the human body. This tissue type performs two main duties, including joint protection and positional information for the brain. Ligaments possess extreme strength, but can become damaged from injuries.
The ligament itself is normally formed of numerous collagen fibers densely packed together. Collagen is produced from fibroblast cells that reside in the fiber's center area. Type 3 collagen is the newly formed tissue from the fibroblasts, remaining near the fiber's center area for development time. This ligament tissue portion is relatively weak until it becomes mature in about three months' time.
After maturing, the collagen becomes Type 1, forming about 90 percent of the fiber's structure. This ligament tissue section provides the strength to connect bone to bone. Each fiber runs parallel to adjacent fiber lengths, creating a strong wall of connective tissue.
One main purpose for ligament tissue is to protect joints. Most joints have numerous ligaments encircling the junction, such as the knee. For example, the knee is allowed to move in a specific direction, as dictated by the ligaments. Improper movement, such as from side to side, is hindered with long ligaments on either side of the knee joint. Unless forced by injury, the ligament will not allow the knee to bend in the wrong direction.
Another ligament tissue task is communicating position to the brain. The ligament sends proprioceptive, or stimulating, data to the brain for determining if the joint is bent or straight. A good example is playing soccer; a player does not need to constantly view his or her knees to know if they are ready for a kick or straightened for a run. This communication from the joints to the brain allows a person to move unimpeded through daily movements.
Ligaments can become damaged through injury, like when performing sports activities. American football players who tackle a competitor on the side of the knee can easily sprain the ligament. Depending on the extent of the damage, the ligament can have a simple inflammatory response and swelling.
Serious ligament tissue damage occurs when the connective fibers become ruptured. In many cases, surgery will need to be performed to repair the ligament's functionality. Without the ligament's strength, the joint is susceptible to more injury. Knees and elbows can accidentally bend in an unnatural way, causing extreme pain and more damage to surrounding tissue.