Goniometer

A goniometer is a calibrated, handheld measuring instrument designed to precisely quantify joint range of motion in degrees. Essential for physical and occupational therapy, orthopedic assessment, and rehabilitation medicine, it consists of a protractor-like body with two arms—one stationary, one movable—that align with the patient's limb segments. Available in various sizes for different joints (from fingers to hips) and in materials including transparent plastic, stainless steel, and digital formats, it transforms subjective observations of mobility into objective, reproducible data. This fundamental clinical tool guides diagnosis, documents treatment progress, supports disability determinations, and provides the evidence base for therapeutic interventions.