Figure 4

Percutaneous kyphoplasty by using the locator. Graph (a) shows that the patient was in the prone position. ML and HL lines, as well as the percutaneous puncture point “P” were marked according to the data acquired from the images preoperatively. Graph (b) illustrates that the locator was placed parallel to the ML line after adjusting for the positions of the hands on dials at the defined angles according to the preoperative measurement of extraversion angle α- and tail tilt angles β. Graphs (c) and (d) display that a cannula was placed in the locator, making the distal end of the cannula aligned with the puncture point “P”, and then, a guide needle was inserted into the cannula until the pedicle bone puncture point was planted into the pedicle. Graph (e) shows that the position of guide needle was confirmed by 2D fluoroscopy. Graph (f) depicts that a saccule was placed through the working channel and the fractured vertebral body was expanded with an appropriate pressure. Then, bone cement was injected into fractured vertebrae to stabilize the spine and relieve pain.