Knee painKnee pain is pain in or around the knee. The knee joint consists of an articulation between four bones: the femur, tibia, fibula and patella. There are four compartments to the knee. These are the medial and lateral tibiofemoral compartments, the patellofemoral compartment and the superior tibiofibular joint. The components of each of these compartments can experience repetitive strain, injury or disease. Running long distance can cause pain to the knee joint, as it is a high-impact exercise.
Patellofemoral pain syndromePatellofemoral pain syndrome (PFPS; not to be confused with jumper's knee) is knee pain as a result of problems between the kneecap and the femur. The pain is generally in the front of the knee and comes on gradually. Pain may worsen with sitting, excessive use, or climbing and descending stairs. While the exact cause is unclear, it is believed to be due to overuse. Risk factors include trauma, increased training, and a weak quadriceps muscle. It is particularly common among runners.
FemurThe femur (ˈfiːmər; : femurs or femora ˈfɛmərə), or thigh bone is the only bone in the thigh. The thigh is the region of the lower limb between the hip and the knee. In many four-legged animals the femur is the upper bone of the hindleg. The top of the femur fits into a socket in the pelvis called the hip joint, and the bottom of the femur connects to the shinbone (tibia) and kneecap (patella) to form the knee. In humans the femur is the largest and thickest bone in the body. The femur is the only bone in the upper leg.
Joint dislocationA joint dislocation, also called luxation, occurs when there is an abnormal separation in the joint, where two or more bones meet. A partial dislocation is referred to as a subluxation. Dislocations are often caused by sudden trauma on the joint like an impact or fall. A joint dislocation can cause damage to the surrounding ligaments, tendons, muscles, and nerves. Dislocations can occur in any major joint (shoulder, knees, etc.) or minor joint (toes, fingers, etc.). The most common joint dislocation is a shoulder dislocation.
JointA joint or articulation (or articular surface) is the connection made between bones, ossicles, or other hard structures in the body which link an animal's 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.
Hyaline cartilageHyaline cartilage is the glass-like (hyaline) and translucent cartilage found on many joint surfaces. It is also most commonly found in the ribs, nose, larynx, and trachea. Hyaline cartilage is pearl-gray in color, with a firm consistency and has a considerable amount of collagen. It contains no nerves or blood vessels, and its structure is relatively simple. Hyaline cartilage is covered externally by a fibrous membrane known as the perichondrium or, when it's along articulating surfaces, the synovial membrane.
TibiaThe tibia (ˈtɪbiə; : tibiae ˈtɪbii or tibias), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outside of the tibia); it connects the knee with the ankle. The tibia is found on the medial side of the leg next to the fibula and closer to the median plane. The tibia is connected to the fibula by the interosseous membrane of leg, forming a type of fibrous joint called a syndesmosis with very little movement.
Varus deformityA varus deformity is an excessive inward angulation (medial angulation, that is, towards the body's midline) of the distal segment of a bone or joint. The opposite of varus is called valgus. Ex: Varus deformity results in a decreased Q angle of the knee joint. The terms varus and valgus always refer to the direction that the distal segment of the joint points. For example, in a valgus deformity of the knee, the distal part of the leg below the knee is deviated outward, in relation to the femur, resulting in a knock-kneed appearance.
Arthropod legThe arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments (called podomeres) are of Latin origin, and may be confused with terms for bones: coxa (meaning hip, plural coxae), trochanter, femur (plural femora), tibia (plural tibiae), tarsus (plural tarsi), ischium (plural ischia), metatarsus, carpus, dactylus (meaning finger), patella (plural patellae). Homologies of leg segments between groups are difficult to prove and are the source of much argument.
CartilageCartilage is a resilient and smooth type of connective tissue. In tetrapods, it covers and protects the ends of long bones at the joints as articular cartilage, and is a structural component of many body parts including the rib cage, the neck and the bronchial tubes, and the intervertebral discs. In other taxa, such as chondrichthyans, but also in cyclostomes, it may constitute a much greater proportion of the skeleton. It is not as hard and rigid as bone, but it is much stiffer and much less flexible than muscle.
