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Objective:To design 3D printed prosthesis in an individualized way and explore the short-term clinical efficacy of reconstruction of segmental defect after resection of bone tumor in lower extremities with 3D-printed prosthesis.Methods:From January 2017 to June 2019, 6 patients with lower limb bone tumor who met the inclusion criteria were recruited, including 3 males and 3 females, aged 8.67±1.11 years (range 6-11 years). All 6 cases were primary bone tumors, and the Enneking stages were all IIB, including 3 cases of left tibial tumors, 2 cases of right tibial tumors, and 1 case of right femoral tumor. These 3D-printed prostheses were designed based on the preoperative imaging data. The mechanical stability of the prosthesis was evaluated by three-dimensional finite element analysis. After tumor resection, the 3D-printed prosthesis was installed and fixed to reconstruct the segmental bone defect. All patients were clinically followed up and evaluated by imaging regularly after operation. The functional status was assessed by the Musculoskeletal Tumor Society (MSTS) score. Oncology results and complications were recorded in detail.Results:All operations were successfully performed, including 3 cases underwent left tibial tumor resection, 2 cases underwent right tibial tumor resection, and 1 case underwent right femoral tumor resection. The length of the bone defect after tumor resection was 18.19±3.74 cm, the average operation time was 165.83±54.17 min, and the average intraoperative bleeding was 233.33±133.33 ml. These finite element analysis data show that the overall stress of these prostheses are lower than the maximum mechanical strength of the corresponding materials. These 3D printed prostheses match well with the excision defect and meet the expected effect. There were no adverse reactions during the operation. The mean follow-up period was 16.83±7.17 months. At the last follow-up, all patients survived without tumor recurrence or metastasis. Postoperative imaging results showed that all the implants were stable without complications such as peripheral infection, aseptic loosening, prosthesis fracture. These 3D-printed prostheses composite resulted in substantial bone integration at follow-up. The average MSTS score was 83.67%±9.11%.Conclusion:The individualized 3D printed prosthesis can be used to reconstruct the bone defect after the resection of osteosarcoma in the lower extremities, and the clinical efficacy was satisfactory in the short-term follow-up.
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Objective:To explore the advantages of the novel individualized 3D printing artificial vertebral body in spine reconstruction and to evaluate its clinical effect.Methods:From January 2017 to December 2018, the 15 patients who underwent total vertebrectomy and spine reconstruction with individualized 3D printing artificial vertebral body were analyzed retrospectively. There were 8 males and 7 females, with the mean age 39.5 years (range: 20-57), including 12 primary tumors and 3 metastatic tumors. According to tumor location and surrounding soft tissue invasion range, simple posterior or combined anterior and posterior approach were used for total vertebral resection, and the defection was reconstructed by 3D printing artificial vertebral body. The operation time, intraoperative bleeding volume, postoperative stability of artificial vertebral body and bone ingrowth of adjacent vertebral body, preoperative and postoperative neurological changes, preoperative and postoperative VAS score, local control and survival of patients were analyzed.Results:The mean operation time was 412.0 min (range: 135-740 min), and the mean blood loss was 4 140.0ml (range: 100-14 000 ml). The mean follow-up time was 23.2 months (range: 12-35 months), and no one loss to follow-up. One case had pleural rupture, one case had cerebrospinal fluid leakage and one case had L5 nerve root palsy. All patients recovered after active symptomatic treatment. Compare with the preoperative VAS score (4.7±1.1), the differences of VAS score at 7 d postoperative and last follow-up (1.6±0.6 and 1.0±0.5) were significantly reduced ( P<0.001). Three patients with Frankel grade C gradually recovered to grade D, and no change were found in grade D and Grade E patients, there was no significant improved at last follow-up. Preliminary bone growth was found between the artificial vertebral body and the adjacent vertebral body 3 months after operation. The bone growth was more obvious at 12 months post-operation, and the artificial vertebral body fused with the adjacent vertebral bodies to form bone integration. At 24 months post-operation, the integration of the artificial vertebral body was more accurate. During the follow-up period, there was no loosening or displacement of the artificial vertebral body and no failure of internal fixation. A case of hemangioendothelioma and a case of epithelioid angiosarcoma died at 33 months and 35 months postoperatively. One patient with chondrosarcoma had local recurrence at16 months post-operation. After treated with arotinib, the tumor did not progress. The other 12 patients had no tumor recurrence or distant metastasis. Conclusion:After spinal tumor resection, individualized 3D printing artificial vertebral body can be used to accurate restoration of spinal continuity, and provide nice interface matching and bone growth between artificial vertebral body and the adjacent vertebral endplates. Moreover, the immediate and long-term stability of the artificial vertebral body can meet the needs of spinal reconstruction.
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Objective@#To investigate the survival rate, function outcomes, and complications after using unicondylar osteoarticular allografts with or without prosthesis to reconstruct the knee joint for tumors located in distal femoral or proximal tibial uni-condyle.@*Methods@#Twenty-two patients who underwent unicondylar osteoarticular allografts with or without prosthesis composite reconstructions from January 2007 to December 2015 in Department of Orthopaedic Surgery of Xi Jing Hospital, the Fourth Military Medical University were retrospectively reviewed. There were 14 males and 8 females and the mean age was 35 years(8-65 years). There were 12 malignent tumors and 10 aggressive benign tumors. The tumors were located in distal femur in 14 cases and proximal tibia in 8 cases. After tumor excision, the distal femur was reconstructed with unicondylar osteoallograft-prosthesis composite, and proximal tibial plate was reconstructed with unicondylar osteoarticular allograft with the help of computer-assisted navigation system. Function and radiograph were documented according to the Musculoskeletal Tumor Society (MSTS) functional scoring system and the International Society of Limb Salvage (ISOLS) radiographic scoring system. The median follow-up time was 60 months (5-116 months).@*Results@#At the latest follow-up, 2 patients had amputation owing to local recurrence in 12 malignant tumors. Three patients had pulmonary metastasis and 1 patient died another 2 alive with disease. Kaplan-Meier analysis indicated that the disease-free survival rate was 73%. There was no recurrence and metastasis in 10 patients with giant cell tumor. The average MSTS score was 26 points and the radiographic score was 78%-94%(average 90%). The complications included superficial infection in 1 patient and screw broken in 1 patient. There was no broken or collapse allograft in all composite reconstruction patients but 6 cases in allograft reconstruction.@*Conclusions@#Unicondylar osteoarticular allografts or prosthesis composite was feasible reconstruction for tumors in distal femoral uni-condyle. It could provide good functional outcomes and also prevent joint degeneration. Similarly, allograft reconstruction was also a reliable technique for proximal tibial defect.
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Objective To explore the effectiveness of our self-designed 3D printing relay template in the treatment of malunion of irregular intra-articular ankle fractures.Methods From October 2013 to October 2015,our self-designed 3D printing relay template was used in 14 patients with severe malunion of intra-articular ankle fracture to assist their intra-articular osteotomy.They were 10 males and 4 females,with an average age of 40.5 years (from 34 to 59 years).Thin slice CT scan was preformed preoperatively for all the ankles involved.The computer fictitious tibial and fibular models for location and osteotomy navigation templates were acquired from the data of CT scan after processing,design and reconstruction by software.After the navigation templates which fit the size of solid ankle were printed by a 3D printer,they were sterilized and reserved.The guide plates were used in turn during operation.The irregular malunited bone blocks in the posterior malleolus were completely resected along the osteotomy template.After fracture reduction,the bone blocks were stabilized with internal fixation.Fracture union time was recorded.Scores of visual analogue scale (VAS),American Orthopaedic Foot and Ankle Society (AOFAS) and the short form-36 (SF-36),ankle ROM and complications were also recorded at the final follow-ups.Results The 14 patients obtained an average follow-up of 28.6 months (from 14 to 35 months).Bony union was achieved after an average of 3.7months (from 3 to 6 months).At the final follow-ups,on average,VAS score (2.2 ± O.8),AOFAS ankle and hindfoot score (81.1 ± 6.8),SF-36 score (82.5 ± 5.2),dorsal extension (27.5 ° ± 2.5°),and plantar flexion (24.2° ±6.3°) were significantly improved compared with the preoperative values (6.3 ± 1.8,43.1 ± 12.0,37.6 ± 9.9,14.1° ± 3.8° and 14.4° ± 3.9°,respectively) (P ＜ 0.05).No implant failure,soft tissue complications or post-traumatic arthritis occurred during the follow-up.Conclusion Since our self-designed 3D printing relay templates for osteotomy can accurately position the fracture lines of the distal tibia via limited incision and invasion,they help a lot in precise osteotomy and anatomical reduction of malunited intra-articular ankle fracture,preventing incidence of traumatic arthritis.
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Objective To explore the feasibility and clinical efficacy of long-segmental bone defects after en bloc tumor resection of lower limb segment with composite of titanium alloy 3D printed prosthesis and vascularized fibular autograft and bioceramics.Methods 5 patients with lower extremity tumor (1 high grade chondrosarcoma,1 Ewing sarcoma,1 single metastatic tumor and 2 osteosarcoma) were treated by en bloc resection and precise reconstruction with segmental 3D-printed,custom-made prosthesis from August 2015 to November 2016,which composed of 1 male and 4 females,ranged from 16 to 56 years old,the average was 32± 19.3 years old.Three-dimensional computed tomography reconstructed images of patients' tumors were built before surgery.Custom-made prostheses were manufactured based on the patients' reconstructed images with micro-pores on the surface.After en bloc tumor resection with the help of osteotomy guide plate,the defects were reconstructed with 3D-printed,custom-made prostheses.Vascularized fibular autografts were put inside the prostheses,and the interval space among them was filled with bioceramics.Results All the 5 cases were performed surgical planning before the surgery with prosthesis and guide plate were designed at the same time.After verification of the finite element analysis SLM (2 cases) and the EBM (3 cases) were used to process prosthesis,and were designed into porous sharp with 210.98±66.16 mm in length and 26 901.76±12 903.96 mm3 in volume.Then the prosthesis would be cleaned and sterilized.All 5 operation were proceeded according to the plan of preoperative.The intra-operative guide plate were installed on the bone surface stably.The bone cutting was guided according to the plan of preoperative.By intra-operative frozen pathological examination,there were no malignant tissues in near and far marrow cavity.Unfolded fibular flap with 168.75±49.07 mm in length and porous tricalcium phosphate particle composite implants with 10±4.08 g were used in 4 cases and bone cement was used in 1 cases of metastatic tumor.The average operation time was 261±85 min and average blood loss was 540±182 ml.After a mean follow-up time of 6.4 months (1-15 months),all 5 cases survived with no local recurrence and pulmonary metastasis tumor.2 cases with vascular pedicle fibular transplant confirmed the survival of fibula via bone scan 3 months after operation.All cases were no infection,fractures,prosthesis loosening,except broken screw in 1 case.The Musculoskeletal Tumor Society (MSTS) 93 score was 17-26.Conclusion Long segment tubular titanium alloy 3D printed prosthesis with vascularized fibular autograft and bioceramics could reconstruct the segmental defects caused by tumor resection.