Search results
Results from the WOW.Com Content Network
Genu recurvatum is a deformity in the knee joint, so that the knee bends backwards. In this deformity, excessive extension occurs in the tibiofemoral joint. Genu recurvatum is also called knee hyperextension and back knee. This deformity is more common in women [citation needed] and people with familial ligamentous laxity. [2]
A digitigrade animal is one that stands or walks with its toes (phalanges) on the ground, and the rest of its foot lifted. Digitigrades include birds (what many see as bird's knees are actually ankles), cats, dogs, and many other mammals, but not plantigrades (such as humans) or unguligrades (such as horses). Digitigrades generally move more ...
The backward-pointing "heel" that is easily visible is a joint between the tibiotarsus and tarsometatarsus. [3] [4] The joint inside the tarsus occurs also in some reptiles. It is worth noting here that the name "thick knee" of the members of the family Burhinidae is a misnomer because their heels are large. [2] [8]
Animals with many legs typically move them in metachronal rhythm, which gives the appearance of waves of motion travelling forward or backward along their rows of legs. Millipedes, caterpillars, and some small centipedes move with the leg waves travelling forward as they walk, while larger centipedes move with the leg waves travelling backward.
Among extinct animals, most early mammals such as pantodonts were plantigrade. A plantigrade foot is the primitive condition for mammals; digitigrade and unguligrade locomotion evolved later. Among archosaurs, the pterosaurs were partially plantigrade and walked on the whole of the hind foot and the fingers of the hand-wing. [1]
The degree of knee extension (the angle between the thigh and shank in a walking cycle) has decreased. The changing pattern of the knee joint angle of humans shows a small extension peak, called the "double knee action," in the midstance phase. Double knee action decreases energy lost by vertical movement of the center of gravity. [1]
With reference to quadrupeds, the term hindleg or back leg is often used instead. In bipedal animals with an upright posture (e.g. humans and some primates ), the term lower limb is often used. Location
Many animals alter walking kinematics as they modulate walking speed. [16] [17] [18] An interlimb kinematic parameter that is commonly speed dependent is gait, the stepping pattern across legs. While some animals alternate between distinct gaits as a function of speed, [19] others move along a continuum of gaits. [20]