Pure Joint Care — Joint Movement and Activity | purejointcare.com
How to measure flexion and extension at the knee and the shoulder in degrees.
Range of motion is the arc a joint can travel, measured in degrees. At the knee, full extension is about 0 degrees and flexion reaches about 135 degrees. At the shoulder, flexion and abduction each reach about 180 degrees in healthy adults.
To measure the knee, place the axis of a goniometer or phone app at the joint line. One arm follows the thigh, the other follows the shin. Record the angle at full extension first, then at maximum comfortable bend.
For the shoulder, stand upright and raise the arm forward for flexion or sideways for abduction. Keep the elbow straight and stop at the first point of compensation, such as leaning back.
On narrow screens, swipe or scroll the plate sideways.
Compare left and right. A difference of about 10 degrees is worth noting, especially if it appeared after an injury or a period of reduced activity.
Range checks are most useful before loading a joint. If extension is short of 0 degrees or flexion is below about 120 degrees, stairs and chairs will feel harder and load should be adjusted.
Repeat the measurement at the same time of day and after the same warm-up so the numbers are comparable over weeks.
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