Flexion is the medical term for bending an arm or leg.

It occurs whenmuscles contractand move your bones and joints into a bent position.

Such extreme movement can potentially result in injury issues to the opposing ligaments, tendons, and muscles.

x ray of a person’s knee

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Extension

The opposite of flexion is extension, which refers to the straightening of ajoint.

In other words, flexion works to shorten a joint angle while extension works to increases it.

Typically, a normal extension of a joint is limited to 180 degrees or less.

In other words, that joint can basically be opened until it is straight.

Hyperextension

Further on the opposite end of the spectrum from flexion ishyperextension.

This is what such a diagnosis is referring to.

Range of Motion

A majority of the human bodys joints allow for some movement.

A few particular joints, like joints in the skull, do not.

This range of motion is basically how far is each direction that joint can move or bend comfortably.

The range of motion of a joint is usually measured in degrees.

Each individual joint has a separaterange of motion.

TeachMe Anatomy.Anatomical terms of movement.

The Free Dictionary: Medical Dictionary.Hyperflexion.

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Orthopedic Specialists of San Diego.Hyperextension injury of the elbow.