A biplanar robot navigation system for the distal locking of intramedullary nails

Background: Distal locking is the key procedure of the intramedullary nailing operation. It is difficult to precisely locate the locking path, and intraoperative radiation exposure is also a serious problem. The advantages and disadvantages of different approaches applied in this operation are summarized. Method: A biplanar robot navigation system for the distal locking of intramedullary nails is presented. The novel mechanical structure and the surgical process are introduced. Then the positioning accuracy of the robot is experimented and validated. Results: The positioning precision of the biplanar robot is tested, and the average error is 0.24 mm. The tibia sawbone is used for distal locking to test the accuracy of the robot navigation system. The maximal deviation between the drilling centre and the nail hole centre is 0.44 mm. Conclusion: The biplanar robot has the advantages of high positioning accuracy, operational stability and safety. It can be used not only for the distal locking of intramedullary nails but also for other orthopaedic surgeries that demand precise positioning.