Knee in the context of "Thigh"

The leg is the entire lower limb of the human body, including the foot, thigh or sometimes even the hip or buttock region. The major bones of the leg are the femur (thigh bone), tibia (shin bone), and adjacent fibula. There are thirty bones in each leg.

The thigh is located in between the hip and knee.

A 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. 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.

Joints play a vital role in the human body, contributing to movement, stability, and overall function. They are essential for mobility and flexibility, connecting bones and facilitating a wide range of motions, from simple bending and stretching to complex actions like running and jumping. Beyond enabling movement, joints provide structural support and stability to the skeleton, helping to maintain posture, balance, and the ability to bear weight during daily activities.

The femur (/ˈfiːmər/; pl.: femurs or femora /ˈfɛmərə/), or thigh bone is the only bone in the thigh — 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.

A boot is a type of footwear. Most boots mainly cover the foot and the ankle, while some also cover some part of the lower calf. Some boots extend up the leg, sometimes as far as the knee or even the hip. Most boots have a heel that is clearly distinguishable from the rest of the sole, even if the two are made of one piece. Traditionally made of leather or rubber, modern boots are made from a variety of materials.

Boots are worn both for their functionality and for reasons of style and fashion. Functional concerns include: protection of the foot and leg from water, mud, pestilence (infectious disease, insect bites and stings, snake bites), extreme temperatures, sharp or blunt hazards (e.g. work boots may provide steel toes), physical abrasion, corrosive agents, or damaging radiation; ankle support and traction for strenuous activities such as hiking; and durability in harsh conditions (e.g. the underside of combat boots may be reinforced with hobnails).

The forearm is the region of the upper limb between the elbow and the wrist. The term forearm is used in anatomy to distinguish it from the arm, a word which is used to describe the entire appendage of the upper limb, but which in anatomy, technically, means only the region of the upper arm, whereas the lower "arm" is called the forearm. It is homologous to the region of the leg that lies between the knee and the ankle joints, the crus.

The forearm contains two long bones, the radius and the ulna, forming the two radioulnar joints. The interosseous membrane connects these bones. Ultimately, the forearm is covered by skin, the anterior surface usually being less hairy than the posterior surface.

The cauda equina (from Latin tail of horse) is a bundle of spinal nerves and spinal nerve rootlets, consisting of the second through fifth lumbar nerve pairs, the first through fifth sacral nerve pairs, and the coccygeal nerve, all of which arise from the lumbar enlargement and the conus medullaris of the spinal cord. The cauda equina occupies the lumbar cistern, a subarachnoid space inferior to the conus medullaris. The nerves that compose the cauda equina innervate the pelvic organs and lower limbs to include motor innervation of the hips, knees, ankles, feet, internal anal sphincter and external anal sphincter. In addition, the cauda equina extends to sensory innervation of the perineum and, partially, parasympathetic innervation of the bladder.

The evolution of human bipedalism, which began in primates approximately four million years ago, or as early as seven million years ago with Sahelanthropus, or approximately twelve million years ago with Danuvius guggenmosi, has led to morphological alterations to the human skeleton including changes to the arrangement, shape, and size of the bones of the foot, hip, knee, leg, and the vertebral column. These changes allowed for the upright gait to be overall more energy efficient in comparison to quadrupeds. The evolutionary factors that produced these changes have been the subject of several theories that correspond with environmental changes on a global scale.

A kick is a physical strike using the leg, in unison usually with an area of the knee or lower using the foot, heel, tibia (shin), ball of the foot, blade of the foot, toes or knee (the latter is also known as a knee strike). This type of attack is used frequently by hooved animals as well as humans in the context of stand-up fighting. Kicks play a significant role in many forms of martial arts, such as capoeira, kalaripayattu, karate, kickboxing, kung fu, wing chun, MMA, Muay Thai, pankration, pradal serey, savate, sikaran, silat, taekwondo, vovinam, and Yaw-Yan. Kicks are a universal act of aggression among humans.

Kicking is also prominent from its use in many sports, especially those called football. The best known of these sports is association football, also known as soccer.