The computer assisted bone bank and its application in individual treatment of bone tumor

Abstract

Objective To investigate the clinical value of a computer assisted bone bank in bone tumor resection and structural allograft bone reconstruction with computer assisted navigation.Methods Bone allografts in the present conventional bone bank in Xijing Hospital were sectionally scanned by CT.Three-dimensional reconstructed images of the CT scans were saved and marked in the digital analytical system to establish a computer assisted bone bank.Before surgery three-dimensional reconstruc ted CT image data of the bone tumor were compared with the allogenic osteoarticular data in the digital bone bank to select an optimum match in bone remodeling segments.Both data were imported at the.dicom 3.0 format into the navigational system to accurately locate borders of the tumor and to cut the allograft bone during the surgery preoperatively designed with the aid of the digital bone bank to get a structural reconstruction.From November 2009 to June 2012,tunor resections and reconstructions under computer navigation assisted by the digital bone bank were performed in 6 patients with malignant bone tumors.The patients were 7 males and 4 females,aged from 13 to 42 years (average,24.7 years).There were 3 cases of giant cell tumor,5 cases of osteosarcoma,2 cases of chondrosarcona and one case of Ewing sarcoma.The oncological and functional outcomes were postoperatively evaluated by the Musculoskeletal Tumor Society 93 (MSTS93) system.Results The computer assisted bone bank obviously shortened the time for selecting allograft bone materials before surgery and improved the matching accuracy,compared with routine preparation of allograft bone.The dissection registration spots in the actual operations matched well with the preoperative three-dimensional reconstructed CT images before surgery,with an average registration error of 0.42 rmm.The 11 patients were followed up from 3 to 30 months (average,15.7 months).Postoperative X-ray images showed that the tumor resection territory and the allograft bone cutting region were totally consistent with the preoperative design in all patients.No limb discrepancy or malformation was observed.No screw loosening or breakage or joint collapse occurred.No obvious immunity rejection,or local recurrence or remote metastasis was observed.The healing between allograft and host bone was achieved after an average of 6.3 months.The average MSTS93 functional score was 25.7 points.Conclusions A digital bone bank can provide accurate information for selecting allograft bone materials before surgery,and allows for individual design of resection and reconstruction protocols which,in combination with computer navigation,may improve the safety and effectiveness of a salvage limb operation. Key words: Bone bank; Bone neoplasms; Surgery, computer-assisted