Range of Motion Calculator

This calculator compares a goniometer-measured joint range against standard normal values to quantify how much motion is missing. Each Joint Type carries its own published normal flexion and extension figures: shoulder flexion to 180° and extension to 60°, elbow flexion to 150° with 0° of extension, hip flexion to 120° and extension to 30°, knee flexion to 135° with 0° of extension, and ankle dorsiflexion to 20° with plantarflexion to 50° -- the ankle entry uses the Measured Flexion field for dorsiflexion and Measured Extension for plantarflexion, since ankle motion is conventionally described in those terms rather than flexion and extension. Flexion Deficit and Extension Deficit subtract your measured values from the joint's normal values, floored at zero so a measurement that meets or exceeds normal never produces a negative deficit. Measured Extension follows standard clinical convention: enter a positive value for hyperextension beyond the joint's normal reference, or a negative value for an extension lag/deficit -- for joints like the elbow and knee, whose normal extension is 0° (fully straight), a negative entry is the only way to represent a real impairment such as a knee that can't fully straighten.

Total ROM simply adds Measured Flexion and Measured Extension together, while Percent of Normal expresses that sum as a share of the joint's full normal arc -- a useful single number for tracking recovery over successive visits. Measured Flexion is capped per joint at a clinically plausible ceiling above its normal value (allowing for natural hypermobility) so an extreme entry can't produce a nonsensical percentage. Because every joint's normal values differ, always confirm Joint Type is set correctly before interpreting a deficit; Joint Type values outside the supported 1-5 set are clamped into range with a warning rather than silently substituted with an unrelated joint's norms.