title: One-step reconstruction with a 3D-printed, custom-made prosthesis after total en bloc sacrectomy: a technical note.
abstract: Surgeries for primary malignancies involving upper sacrum require total en bloc sacrectomy followed by complex mechanical reconstruction, which might be simplified by application of the three-dimensional (3D) printing technique.
  
  
  
  To describe the design of a 3D-printed custom-made prosthesis for reconstruction after total en bloc sacrectomy, the surgical technique, and the clinical and functional outcome of a patient.
  
  
  
  A 62-year-old patient with recurrent sacral chordoma was admitted in our center. One-stage total en bloc sacrectomy through posterior approach was planned, and a 3D-printed sacral prosthesis was prepared for reconstruction according to the anticipated osteotomic planes.
  
  
  
  The patient received one-stage total en bloc sacrectomy through posterior approach followed by reconstruction with the 3D-printed sacral prosthesis. The whole procedure took 5 h, and intra-operative blood loss was 3400 ml. The patient recovered uneventfully and started ambulation at 3 weeks after surgery. An asymptomatic instrument failure was found radiographically at 8-month follow-up. At 1 year after surgery, the patient was disease free and could walk over short distance with crutches without pain or any mechanical instability.
  
  
  
  The advantages of our reconstruction method included: (1) the prosthesis provided an optimal reconstruction of lumbosacral and pelvic ring by integrating spinal pelvic fixation, posterior pelvic ring fixation, and anterior spinal column fixation in one step and (2) its porous surface could induce bone ingrowth and might enhance stability. Although there was an instrumental failure, we considered that it could be one reconstructive option. More research is warranted focusing on the modification of locations, diameters, and quantity of screws and biomechanical characteristics. The long-term functional and bone in-growth outcome will be followed to validate the use of the prosthesis.
authors.affiliation: Musculoskeletal Tumor Center, Peking University People's Hospital, No. 11 Xizhimen South Street, Xicheng District, Beijing, 100044, China.
authors.forename: Ran
authors.initials: R
authors.lastname: Wei
authors.affiliation: Musculoskeletal Tumor Center, Peking University People's Hospital, No. 11 Xizhimen South Street, Xicheng District, Beijing, 100044, China. bonetumor@163.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
authors.affiliation: Musculoskeletal Tumor Center, Peking University People's Hospital, No. 11 Xizhimen South Street, Xicheng District, Beijing, 100044, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Ji
authors.affiliation: Musculoskeletal Tumor Center, Peking University People's Hospital, No. 11 Xizhimen South Street, Xicheng District, Beijing, 100044, China.
authors.forename: Yidan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Musculoskeletal Tumor Center, Peking University People's Hospital, No. 11 Xizhimen South Street, Xicheng District, Beijing, 100044, China.
authors.forename: Haijie
authors.initials: H
authors.lastname: Liang
mesh_terms: D002817:Chordoma / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D066330:Printing, Three-Dimensional; D019736:Prostheses and Implants; D019919:Prosthesis Implantation / Q000295:instrumentation / Q000379:methods*; D019651:Plastic Surgery Procedures / Q000295:instrumentation / Q000379:methods*; D012447:Sacrum / Q000601:surgery*; D013125:Spinal Neoplasms / Q000601:surgery*
keywords: 3D printing; Chordoma; Oncology; Prosthesis; Reconstruction; Total en bloc sacrectomy