Paragraph Number

6

Implementations may include one or more of the following features. The surgical device may include a calibration circuit configured to determine a reference axis for the electronic circuit, the reference axis being perpendicular to a horizontal plane of a surgical field. The housing may include a planar surface and the electronic circuit determines the horizontal plane based on the planar surface resting on skin of the patient and substantially centered above a patient’s spine of a patient in a prone position and based on a zero-out input signal from a user. The calibration circuit determines the reference axis in response to a zero-out input signal from a user. The electronic circuit may include a sensor configured to determine a horizontal plane and the electronic circuit determines the reference axis relative to the horizontal plane. The surgical device may include a linear measurement circuit configured to measure a linear distance between the surgical device and a second surgical device.

Added by DJM 1 2022