The term goniometry is derived from two greek words, gonio, meaning angle, and metron, meaning measure. Therefore, goniometry refers to the measurement of angles, in particular the measurement of angles created by human joints.
Types of goniometry
- Universal goniometry: These are most commonly used instrument. The body of a universal goniometer resembles a protractor and may from full or half circle. Measurement scales are located on the body (0-180 or 0-360). It consists of two arms stationary or fixed arm and movable arm. Stationary can not be moved. Movable arm is attached to the fulcrum which is the center of the body and it can be moved. It contain a black line extend the length of the arm for measuring the angle.
- Gravity dependent goniometers: These are sometimes called inclinometers. They use gravity’s effect on pointers and fluid levels to measure joint position and motion.
- Electro goniometers: These are used primarily in research to obtain dynamic joint measurements. It is similar to that of universal goniometer.
- Visual estimation: Although some examiners make visual estimates of joint position and motion but it is not a recommended position.
- Pendulum goniometer: It consists of a 360 degree protractor with a weighted pointer hanging from the center of the protractor.
- Fluid goniometer: It has fluid filled circular chamber containing an air bubble.
It is similar to a carpenter’s level, but being circular, has a 360 degree scale.