Fig. 1.

The gesture control software used to convert and immobilize the virtual image. A Direction gesture. The palm is opened and positioned inward. The direction of the index finger represents the superior direction of the patient’s real lumbar spine. The HoloLens quickly recognizes the gesture and automatically adjusts the superior direction of the virtual spine image to be consistent with the direction of the index finger. The virtual image can follow the movement of the palm. B Lock/unlock gesture. Two fists are made in 2 s. The HoloLens automatically fixes the virtual image, which will no longer move with the palm. C The visual effect of the image conversion functions conducted by the gesture control software in the HoloLens