Fig. 1

Principle of closed biopsy of bone tumor with built-in channel device. a The puncture needle was put into the cannula of the passage and penetrated into the skin, subcutaneous tissue, and bone cortex to enter the tumor site. b Fix the puncture sleeve with temporary fixing device. c The pathological cannula was used to remove the bone tissue through the passage. d After sampling, the tail cap was implanted into the casing to block the puncture hole. e Remove the fixator and screw the sleeve under the skin. f The built-in channel is fixed to the puncture bone hole, so as to achieve the purpose of blocking the pathological approach. In addition, (1) internal passage, (2) puncture needle, (3) temporary fixator, (4) removal of pathological sleeve, (5) closure of tail cap, (6) skin, (7) subcutaneous tissue, (8) cortical bone, and (9) medullary cavity