Fig. 4From: Potential risk analysis and experience summarization of unstable factors of cranial fixation devices in neurosurgical operations: three-case reports and systematic reviewThe relation between the position of the cranial fixation devices and the center of the head. a The center of the head is located at the upper part of the three-point center of gravity of the head frame. b The center of the head is located at the lower part of the three-point center of gravity of the head frameBack to article page