How to Measure Range of Motion

Diagnosing a joint injury or chronic problem can best be accomplished by determining a subject's full range of motion. Most joints have two basic measurements: flex and extension. Combined, they allow us to do a full range of activities. For example, roll your shoulder in its socket--this is one expression of your shoulder's range of motion; reach out to grab something in front of you--this is another expression of your shoulder's extension capabilities. Knowing how to take range of motion measurements can prove invaluable in a variety of situations.

Things You'll Need

  • Range of motion measurement guide
  • Goniometer
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Instructions

    • 1

      Reference the medically established standard range of motion. Since the range of motion is the measurement of a joint going through a normal range of movements, there is a great deal of overlap from person to person (see Resources).

    • 2

      Maneuver a patient's arm directly to take a measurement of passive range of motion. Have the patient stand as limp as possible while allowing you to flex and extend the muscle.

    • 3

      Take a reading measuring the full angle of the range of motion using a goniometer, which is basically a specialized protractor (see Resources). Hold the protractor with the curve representing the natural range of motion and the poseable bar at the position of the subject. Measure the maximum change in degrees when you passively manipulate the patient's joint or limb

    • 4

      Conduct an active range of motion test. Encourage the patient to demonstrate his range of motion without your assistance, which will often amplify range of motion limitations. Factors such as pain, disease and swelling can be observed more readily by watching the patient's reaction to his own motion.

    • 5

      Take the same measurements for the active range of motion. Using the goniometer, measure the angle of flex available to the patient. With two arms extended from body, the goniometer is strapped to both ends of a joint, such as the upper and lower arm.