A 'Goniometer' is essentially a protractor with two long arms, one of which is stationary and structurally a part of the body of the goniometer and the other, a moving arm that follows a physiological landmark through its range of movement.

We offer a range of Goniometers at both 180 and 360 degrees and in a choice of sizes to suit the measurement of different joints and adults & children.

We also supply a Clinical Inclinometer' that uses gravity as its reference, rather than magnetic north, and consequently is used vertically, whereas a compass is used horizontally.
Instead of a needle, there is a semi-circular column of coloured fluid, the two ends of which are always level with each other. The dial is turned so that the arrow points to the meniscus (the curved uppermost surface of a liquid in a tube), at the top of the fluid column.
Angles about the horizontal can now be measured by reading the dial where the meniscus crosses it. This is true, irrespective of the shape of the subject, or where on the limb the device is placed.