Does Intraoperative Navigation Assistance Improve Bone Tumor Resection and Allograft Reconstruction Results?

Abstract

Background Bone tumor resections for limb salvage have become standard treatment. Recently, computer-assisted navigation has been introduced to improve the accuracy of joint arthroplasty and possible tumor resection surgery; however, like with any new technology, its benefits and limitations need to be characterized for surgeons to make informed decisions about whether to use it. Questions/purposes We wanted to (1) assess the technical problems associated with computer-assisted navigation; (2) assess the accuracy of the registration technique; (3) define the time required to perform a navigated resection in orthopedic oncology; and (4) the frequency of complications such as local recurrence, infection, nonunion, fracture, and articular collapse after tumor resection and bone reconstruction with allografts using intraoperative navigation assistance. Methods We analyzed 69 consecutive patients with bone tumors of the extremities that were reconstructed with massive bone allografts using intraoperative navigation assistance with a minimum followup of 12 months (mean, 29 months; range, 12-43 months). All patients had their tumors reconstructed in three-dimensional format in a virtual platform and planning was performed to determine the osteotomy position according to oncology margins in a CT-MRI image fusion. Tumor resections and allograft reconstructions were performed using a computer navigation system according to the previously planned cuts. We analyzed intraoperative data such as technical problems related to the navigation procedure, registration technique error, length of time for the navigation procedure, and postoperative complications such as local recurrence, infection, nonunion, fracture, and articular collapse. Results In three patients (4%), the navigation was not carried out as a result of technical problems. Of the 66 cases in which navigation was performed, the mean registration error was 0.65 mm (range, 0.3-1.2 mm). The mean required time for navigation procedures, including bone resection and allograft reconstruction during surgery, was 35 minutes (range, 18-65 minutes). Complications that required a second surgical procedure were recorded for nine patients including one local recurrence, one infection, two fractures, one articular collapse, and four nonunions. In two of these nine patients, the allograft needed to be removed. At latest followup, three patients died of their original disease. Conclusions The navigation procedure could not be performed for technical reasons in 4% of the series. The mean registration error was 0.65 mm in this series and the navigation procedure itself adds a mean of 35 minutes during

What Is the Expected Learning Curve in Computer-assisted Navigation for Bone Tumor Resection?

“…The median registration error was 0.6 mm (range, 0.3-1.1 mm). This error is similar to that observed in previous publications [1,2,10,17,21,22]. In our study, the amount of registration error did not improve overtime (Fig.…”

“…Using MIMICS 1 software (Materialise, Leuven, Belgium), the affected bone was reconstructed with the tumor and the osteotomies for tumor resection were planned in an oncologic meeting. The virtual surgical planning was imported back into a navigation system (Stryker Navigation System II, Orthomap software Version 1.0, Freiburg, Germany) [1]. One centimeter was considered the minimum bone margin for malignant tumors and 0.5 cm in benign or local aggressive tumors.…”

“…However, previous reports about navigation in trauma and arthroplasty have suggested that computer assistance techniques do not improve patient-reported outcomes and that these techniques add surgical time [6,8,13,20]. Intraoperative problems and increased surgical time might be expected with the adoption of new technology, and a learning curve may apply to surgeons who attempt new methods like navigation [1,12,17].…”

“…We therefore attempted to answer the following study questions: (1) What intraoperative technical problems were observed during the first 2 years using navigation? (2) What was the mean time for navigation procedures and the time improvement during the learning curve?…”

Hemicortical Resection and Inlay Allograft Reconstruction for Primary Bone Tumors

“…Additional factors should, however, be considered. First, perfect fitting of allografts may reduce fracture rates 26 . Three-dimensional CT scanning of allografts may aid in the selection of better-fitting grafts 27 .…”