Use of a patient-specific CAD/CAM surgical jig in extremity bone tumor resection and custom prosthetic reconstruction

Computer navigation has recently been introduced for bone tumor surgery in the orthopedic field, with the aim of achieving increased accuracy and precision in tumor resection and in custom prosthetic reconstruction. However, the technique requires bulky navigation facilities, the presence of a system operator in the operating room, and surgeons with prior experience in navigated surgery. We describe a new and simple method of using a patient-specific computer-aided design/computer-aided modeling (CAD/CAM) surgical jig to realize the preoperative planning in the surgical field. The accuracy of the proposed method was first tested in a cadaver trial. It took one minute to set the location of the jig prior to the bone resection and three minutes to perform the bone resections via the cutting slits of the jig. The dimensional difference between the achieved and planned bone resection was <1 mm on validation with the help of a junctional plate and a navigation system. The technique was then applied successfully to a patient with a low-grade osteosarcoma of the femur. An intercalated tumor resection was performed using a patient-specific surgical jig, and a custom CAD prosthesis reconstruction matched accurately to the skeletal defect. Further assessment in a larger population is necessary to determine the clinical efficacy of the technique.