Complex joint-preserving bone tumor resection and reconstruction using computer navigation and 3D-printed patient-specific guides: A technical note of three cases.

In selected extremity bone sarcomas, joint-preserving surgery retains the natural joints and nearby ligaments with a better function than in traditional joint-sacrificing surgery. Geometric multiplanar osteotomies around bone sarcomas were reported with the advantage of preserving more host bone. However, the complex surgical planning translation to the operating room is challenging. Using both Computer Navigation and Patient-Specific Guide may combine each technique's key advantage in assisting complex bone tumor resections. Computer Navigation provides the visual image feedback of the pathological information and validates the correct placement of Patient-Specific Guide that enables accurate, guided bone resections. We first described the digital workflow and the use of both computer navigation and patient-specific guides (NAVIG) to assist the multiplanar osteotomies in three extremity bone sarcoma patients who underwent joint-preserving bone tumor resections and reconstruction with patient-specific implants. The NAVIG technique verified the correct placement of patient-specific guides that enabled precise osteotomies and well-fitted patient-specific implants. The mean maximum deviation errors of the nine achieved bone resections were 1.64 â€‹± â€‹0.35 â€‹mm (95% CI 1.29 to 1.99). The histological examination of the tumor specimens showed negative resection margin. At the mean follow-up of 55 months (40-67), no local recurrence was noted. There was no implant loosening that needed revision. The mean MSTS score was 29 (28-30) out of 30 with the mean knee flexion of 140° (130°-150°). The excellent surgical accuracy and limb function suggested that the NAVIG technique might replicate the surgical planning of complex bone sarcoma resections by combining the strength of both Computer Navigation and Patient-Specific Guide. The patient-specific approach may translate into clinical benefits. The translational potential of this article: The newly described technique enhances surgeons' capability in performing complex joint-preserving surgery in bone sarcoma that is difficult to be achieved by the traditional method. The high precision and accuracy may translate into superior clinical outcomes.