Back Pain Expert Doctors – Day Treatment,Fast Recovery by Singapore Spine and Pain Experts
Back Injuries – Fast, Safe and Effective Clinical Treatment For Back Injuries
Extension is a movement of a joint that results in increased angle between two bones or body surfaces at a joint. Extension usually results in straightening of the bones or body surfaces involved. For example, extension is produced by extending the flexed (bent) elbow. Straightening of the arm would require extension at the elbow joint. If the head is tilted all the way back, it is said to be extended.
In some anatomical muscle names, particularly with muscles of the forearm and the Cnemis, the term occurs explicitly as the second word in the Latin spelling of the name (for example, Musculus extensor carpi ulnaris).
While extension is a movement, the terms “extend” versus “flexed” refer to the final position of a body part with reference to the anatomical position of the body. For example, if an arm fully bent at the elbow is slightly extended, it will still be called “flexed” or “semiflexed”, and will be called “extended” only upon complete straightening of the arm.
The movement in the opposite directions is called flexion. Flexion decreases the angle between the bones of the limb at a joint, while extension increases it.
With the foot, extension (elevation) is usually called dorsiflexion.
If a part of the body such as a joint is overstretched or “bent backwards” because of exaggerated extension motion, then one speaks of a hyperextension (as with the knee). This puts a lot of stress on the ligaments of the joint, and need not always be a voluntary movement, but may occur as part of accidents, falls, or other causes of trauma.
Leave a reply