and stiffness. There are three types of range of motion exercises: Passive range of motion (or PROM) – Therapist or equipment moves the joint through the range of motion with no effort from the patient. Active assisted range of motion (or AAROM) – Patient uses the muscles surrounding the joint to perform the exercise but requires some help from the therapist or equipment (such as a strap). Active range of motion (or AROM) – Patient performs the exercise to move the joint without any assistance to the muscles surrounding the joint. See also Joint locking (symptom) Hypermobility References A Goniometer is used to measure range of motion of the joints of the body and its parts. It uses a stationary arm, fulcrum, and movement arm to measure joint angles from the axis of the joint. Of all the types, a universal goniometer is most widely used and comes in two forms: short arm and long arm. Mechanical engineering Massage therapy