Preliminary Results of a 3D‐Printed Modular Vertebral Prosthesis for Anterior Column Reconstruction after Multilevel Thoracolumbar Total En Bloc Spondylectomy
Authors: Tang Xiaodong , Yang Yi , Zang Jie , Du Zhiye , Yan Taiqiang , Yang Rongli , Guo Wei 
Published: April 2021

Objective

To evaluate preliminary results of a 3D‐printed modular prosthesis for spinal reconstruction after multilevel thoracolumbar total en bloc spondylectomy (TES).

Methods

Patients with thoracolumbar spinal tumors treated surgically between January 2016 and April 2019 were included in this retrospective study. A total of 17 male and 10 female patients with a mean age of 42 (range, 15–72) years comprised the sample. The pathological diagnoses included six chondrosarcomas (one of them was mesenchymal chondrosarcoma), six giant cell tumors, three malignant peripheral nerve sheath tumors, two osteosarcomas, two undifferentiated high‐grade pleomorphic sarcomas (UPS), two solitary fibrous tumors, one Ewing's sarcoma, one liposarcoma, and four metastatic tumors. Tumors involved 2 levels in 14 patients, 3 levels in seven patients, 4 levels in four patients, 5 levels in one patient, and 6 levels in one patient. A 3D‐printed modular prosthesis was used for anterior column reconstruction after TES. All analyses were performed using SPSS version 18.0 (SPSS, Inc., Chicago, IL). Descriptive statistics were used to analyze the demographic data and clinical outcomes. Data forms included mean, standard deviation and range.

Results

Under general anesthesia, all patients received TES with an average operative time of 639 (range, 210–1650) min, and the mean blood loss during operation was 4.1 (range, 0.8–13.3) L. Twenty‐two patients have been transferred to ICU for a mean time of 3.2 (range, 0–6) d. All patients had follow‐up procedures except for one, who died of perioperative complications. Mean time of follow‐up was 22 (range, 12–41) months. Local recurrence (19.2%) occurred in two patients with intralesional margin and three patients with marginal margin, respectively. At the end of follow‐up, three patients died of disease, eight patients were alive with disease, and 15 patients had no evidence of disease. Average lengths of resected vertebrae and modular prostheses were 71.4 ± 26.5 mm (range, 40–142 mm) and 68.4 ± 23.9 mm (range, 40–132 mm), respectively. In 26 patients with minimum follow‐up of more than 1 year, no evidence of internal fixation failure or dislocation of vertebral prosthesis was found. Asymptomatic prosthetic subsidence into adjacent vertebral bodies occurred in 10 patients with a mean length of 1.8 ± 1.0 mm (range, 1–4 mm). The subsidence was seen at proximal end in two patients, distal end in four patients, and both ends in four patients. Eighteen major complications and 14 minor complications were found in 15 patients. All patients fully recovered at 3 or 6 months after operation. At the latest follow‐up, in 23 alive patients, 19 can walk independently and two can achieve outdoor activities by walking aid.

Conclusion

For spinal reconstruction after multilevel thoracolumbar TES, 3D‐printed modular vertebral prosthesis is suitable for different length of anterior column reconstruction with less mechanical complications, and can provide a stable environment to maintain or rehabilitate patients' neurological function in short‐term follow‐up.