Information:  - Cruciate ligaments (also cruciform ligaments) are pairs of ligaments arranged like a letter X. They occur in several joints of the body, such as the knee. In a fashion similar to the cords in a toy Jacob's ladder, the crossed ligaments stabilize the joint while allowing a very large range of motion.  - The tibia (plural tibiae or tibias), also known as the shinbone or shankbone, is the larger and stronger of the two bones in the leg below the knee in vertebrates (the other being the fibula), and it connects the knee with the ankle bones. The tibia is found on the medial side of the leg next to the fibula, and closer to the median plane or centre-line. The tibia is connected to the fibula by the interosseous membrane of the leg, forming a type of fibrous joint called a syndesmosis with very little movement. The tibia is named for the flute "tibia". It is the second largest bone in the human body next to the femur. The leg bones are the strongest long bones as they support the rest of the body.  - The anterior cruciate ligament (ACL) is one of a pair of cruciate ligaments (the other being the posterior cruciate ligament) in the human knee. They are also called "cruciform" ligaments as they are arranged in a crossed formation. In the quadruped stifle joint (analogous to the knee), based on its anatomical position, it is also referred to as the cranial cruciate ligament. The anterior cruciate ligament is one of the four main ligaments of the knee, and the ACL provides 85% of the restraining force to anterior tibial displacement at 30 degrees and 90 degrees of knee flexion.  - The femur (pl. "femurs" or "femora" ) or thigh bone, is the most proximal (closest to the hip joint) bone of the [leg] in tetrapod vertebrates capable of walking or jumping, such as most land mammals, birds, many reptiles such as lizards, and amphibians such as frogs. In vertebrates with four legs such as dogs and horses, the femur is found only in the hindlimbs. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with the tibia and kneecap forming the knee joint. By most measures the femur is the strongest bone in the body. The femur is also the longest bone in the body.  - The patella, also known as the kneecap or kneepan, is a thick, circular-triangular bone which articulates with the femur (thigh bone) and covers and protects the anterior articular surface of the knee joint. The patella is found in many tetrapods, such as mice, cats, and birds, but not in whales, most reptiles nor amphibians such as frogs.  - In humans, the thigh is the area between the pelvis and the knee. Anatomically, it is part of the lower limb.  - Osteoarthritis (OA) is a type of joint disease that results from breakdown of joint cartilage and underlying bone. The most common symptoms are joint pain and stiffness. Initially, symptoms may occur only following exercise, but over time may become constant. Other symptoms may include joint swelling, decreased range of motion, and when the back is affected weakness or numbness of the arms and legs. The most commonly involved joints are those near the ends of the fingers, at the base of the thumb, neck, lower back, knee, and hips. Joints on one side of the body are often more affected than those on the other. Usually the symptoms come on over years. It can affect work and normal daily activities. Unlike other types of arthritis, only the joints are typically affected. Causes include previous joint injury, abnormal joint or limb development, and inherited factors. Risk is greater in those who are overweight, have one leg of a different length, and have jobs that result in high levels of joint stress. Osteoarthritis is believed to be caused by mechanical stress on the joint and low grade inflammatory processes. It develops as cartilage is lost and the underlying bone becomes affected. As pain may make it difficult to exercise, muscle loss may occur. Diagnosis is typically based on signs and symptoms, with medical imaging and other tests occasionally used to either support or rule out other problems. In contrast to rheumatoid arthritis, which is primarily an inflammatory condition, in osteoarthritis, the joints do not typically become hot or red. Treatment includes exercise, efforts to decrease joint stress, support groups, and pain medications. Efforts to decrease joint stress include resting and the use of a cane. Weight loss may help in those who are overweight. Pain medications may include paracetamol (acetaminophen) as well as NSAIDs such as naproxen or ibuprofen. Long-term opioid use is generally discouraged due to lack of information on benefits as well as risks of addiction and other side effects. If...  - Arthritis is a term often used to mean any disorder that affects joints. Symptoms generally include joint pain and stiffness. Other symptoms may include redness, warmth, swelling, and decreased range of motion of the affected joints. In some types other organs are also affected. Onset can be gradual or sudden. There are over 100 types of arthritis. The most common forms are osteoarthritis (degenerative joint disease) and rheumatoid arthritis. Osteoarthritis usually occurs with age and affects the fingers, knees, and hips. Rheumatoid arthritis is an autoimmune disorder that often affects the hands and feet. Other types include gout, lupus, fibromyalgia, and septic arthritis. They are all types of rheumatic disease. Treatment may include resting the joint and alternating between applying ice and heat. Weight loss and exercise may also be useful. Pain medications such as ibuprofen and paracetamol (acetaminophen) may be used. In some a joint replacement may be useful. Osteoarthritis affects more than 3.8% of people while rheumatoid arthritis affects about 0.24% of people. Gout affects about 1 to 2% of the Western population at some point in their lives. In Australia about 15% of people are affected, while in the United States more than 20% of have a type of arthritis. Overall the disease becomes more common with age. Arthritis is a common reason that people miss work and can result in a decreased quality of life. The term is from Greek "arthro-" meaning joint and "-itis" meaning inflammation.  - The anterior cruciate ligament ( `` ACL '' ) is an important , internal , stabilizer of the knee joint , restraining hyperextension . It is injured when its biomechanical limits are exceeded ( over stretched ) , often with a hyperextension mechanism . Formerly , ACL injuries occurred most often in a sports contact injury , when other structures were frequently involved . A particularly severe form of the contact injury is called the `` unhappy triad '' or `` O'Donaghue 's triad '' , and involves the anterior cruciate ligament , the medial collateral ligament , and the medial meniscus . Presently , ACL injury is more commonly a non-contact injury , such as a dismount from a layup in basketball . Both forms occur more frequently in athletes than in the general population and are prevalent in alpine skiing , association football , American football , Australian rules football , basketball , rugby , professional wrestling , martial arts , and artistic gymnastics . It is also known to be about three times more common in women than men . The consequences of the injury depend on how much the stability of the knee is affected , and the extent to which other structures have been involved , and this can vary on a case - by - case basis . If instability is evident , particularly rotatory instability , then the menisci will get injured , sooner or later , setting the scene for progressive , degenerative , arthritis of the knee .  - A hinge joint (ginglymus) is a bone joint in which the articular surfaces are molded to each other in such a manner as to permit motion only in one plane. According to one classification system they are said to be uniaxial having one degree of freedom.  The direction which the distal bone takes in this motion is seldom in the same plane as that of the axis of the proximal bone; there is usually a certain amount of deviation from the straight line during flexion.   - Modern humans ("Homo sapiens", primarily ssp. "Homo sapiens sapiens") are the only extant members of Hominina tribe (or human tribe), a branch of the tribe Hominini belonging to the family of great apes. They are characterized by erect posture and bipedal locomotion; manual dexterity and increased tool use, compared to other animals; and a general trend toward larger, more complex brains and societies.  - A joint or articulation (or articular surface) is the connection made between bones in the body which link the skeletal system into a functional whole. They are constructed to allow for different degrees and types of movement. Some joints, such as the knee, elbow, and shoulder, are self-lubricating, almost frictionless, and are able to withstand compression and maintain heavy loads while still executing smooth and precise movements. Other joints such as sutures between the bones of the skull permit very little movement (only during birth) in order to protect the brain and the sense organs. The connection between a tooth and the jawbone is also called a joint, and is described as a fibrous joint known as a gomphosis. Joints are classified both structurally and functionally.  - The stifle joint (often simply stifle) is a complex joint in the hind limbs of quadruped mammals such as the sheep, horse or dog. It is the equivalent of the human knee and is often the largest synovial joint in the animal's body. The stifle joint joins three bones: the femur, patella, and tibia. The joint consists of three smaller ones: the femoropatellar joint, medial femorotibial joint, and lateral femorotibial joint.  - The knee joint joins the thigh with the leg and consists of two articulations: one between the femur and tibia (tibiofemoral joint), and one between the femur and patella (patellofemoral joint). It is the largest joint in the human body. The knee is a modified hinge joint, which permits flexion and extension as well as slight internal and external rotation. The knee joint is vulnerable to injury and to the development of osteoarthritis.  - The posterior cruciate ligament (or PCL) is one of the four major ligaments of the knee. It connects the posterior intercondylar area of the tibia to the medial condyle of the femur. This configuration allows the PCL to resist forces pushing the tibia posteriorly relative to the femur.  - In anatomy, a ligament is the fibrous connective tissue that connects bones to other bones and is also known as "articular ligament", "articular larua", "fibrous ligament", or "true ligament".    After reading the paragraphs above, we are interested in knowing the entity with which 'anterior cruciate ligament injury' exhibits the relationship of 'instance of'. Find the answer from the choices below.  Choices: - 1  - addiction  - age  - anatomy  - animal  - area  - articulation  - bone  - brain  - cause  - complex  - condition  - constant  - degree  - direction  - disease  - dog  - family  - fibula  - formation  - four  - head  - homo  - horse  - human  - humans  - injury  - joint  - jumping  - ladder  - letter  - ligament  - line  - may  - membrane  - motion  - plane  - population  - result  - sense  - skull  - surgery  - synovial joint  - term  - three  - time  - tribe  - two
The answer to this question is:
disease