How to Measure Range of Motion of Forearm Supination

Forearm supination is the ability to twist the lower arm to position the hand with the palm up. Supination of the forearm requires the radius bone, located along the thumb-side of the forearm, to rotate over the ulna bone, located along the fifth finger of the forearm. For proper measurements to be taken of forearm supination, knowledge of normal range of motion--between 80 and 90 degrees--and proper use of a goniometer are necessary. A goniometer is a hand-held tool used to measure angles, available at rehab specialty stores.

Things You'll Need

• Goniometer

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Instructions

Measuring forearm supination

• 1

  Flex or bend the elbow ninety degrees. Position the upper arm against the torso and the lower arm out in front of the body parallel to the floor with the thumb in an upward position.

• 2

  Position the goniometer in a vertical position against the inside of the wrist.

• 3

  Move the wrist through the available supination range of motion to position the palm so it faces upwards.

• 4

  Maintain the stationary lever arm of the goniometer in the vertical position while moving the other lever to rest against the anterior (inner) surface of the wrist.

• 5

  Read the amount of movement, measured in degrees.