In this article, we introduce the principle, describe the utilization and discuss the future development of three-dimensional printing technology for manufacturing artificial organs.
ObjectiveTo explore the effectiveness and advantage of three-dimensional (3D) printed navigation templates assisted Ludloff osteotomy in treatment of moderate and severe hallux valgus.MethodsBetween April 2013 and February 2015, 28 patients (28 feet) with moderate and severe hallux valgus who underwent Ludloff osteotomy were randomly divided into 2 groups (n=14). In group A, the patients were treated with Ludloff osteotomy assissted with a 3D printed navigation template. In group B, the patients were treated with traditional Ludloff osteotomy. There was no significant difference in gender, age, affected side, and clinical classification between 2 groups (P>0.05). The operation time and intraoperative blood loss were recorded. The ankle function of the foot at preoperation, immediate after operation, and last follow-up were assessed by the American Orthopedic Foot and Ankle Society (AOFAS) score. Besides, the X-ray film were taken to assess the hallux valgus angle (HVA), intermetatarsal angle (IMA), and the first metatarsal length shortening.ResultsAll patients were followed up 18-40 months (mean, 26.4 months). The operation time and intraoperative blood loss in group A were significantly less than those in group B (P<0.05). The HVA, IMA, and AOFAS scores in groups A and B at immediate after operaton and last follow-up were sinificantly improved when compared with preoperative values (P<0.05); but no significant difference was found between at immediate after operation and at last follow-up (P>0.05). No significant difference was found in HVA and IMA between group A and group B at difference time points (P>0.05). There were significant differences in AOFAS score and the first metatarsal length shortening at immediate after operation and at last follow-up between 2 groups (P<0.05). Except 1 case of metastatic metatarsalgia in group B, there was no other operative complications in both groups.Conclusion3D printed navigation template assisted Ludloff osteotomy can provide accurate preoperative planning and intraoperative osteotomy. It is an ideal method for moderate and severe hallux valgus.
Objective To investigate the effectiveness of sacroiliac screw implantation assisted by three-dimensional (3D) printed faceted honeycomb guide plate in the treatment of posterior pelvic ring fracture. Methods The clinical data of 40 patients with posterior pelvic ring fractures treated with sacroiliac screw implantation between December 2019 and December 2022 were retrospectively analyzed. Among them, 18 cases were treated with sacroiliac screws fixation assisted by 3D printed faceted honeycomb guide plate (guide plate group), and 22 cases were treated with sacroiliac screws percutaneously fixation under fluoroscopy (conventional group). There was no significant difference in baseline data (P>0.05) such as gender, age, time from injury to operation, and Dennis classification between the two groups. The implantation time, frequency of C-arm X-ray fluoroscopy, frequency of guide pin adjustment of each sacroiliac screw, and postoperative complications and bone healing were recorded. Majeed score was used to evaluate the functional recovery at 6 months after operation, and CT was used to observe whether the screw penetrated the bone cortex. The deviation between the virtual position and the actual position of the screw tip, the sacral foramen, and the screw entry point was measured on the sagittal CT images of the guide plate group. Results The number of screws implanted in S1 and S2 vertebral bodies was 14 and 16 respectively in the guide plate group, and 17 and 18 respectively in the conventional group. The implantation time of each sacroiliac screw, the frequency of C-arm X-ray fluoroscopy, and the frequency of guide pin adjustment in S1, S2, and all vertebrae in the guide plate group were significantly less than those in the conventional group (P<0.05). Patients in both groups were followed up 8-48 months, with an average of 19.7 months. There was no incision infection, screw displacement, or internal fixation loosening in both groups. Callus growth was observed in all patients at 12 weeks after operation, and bone healing was achieved in all patients. The healing time ranged from 12 to 24 weeks, with an average of 15.7 weeks. No sacroiliac screw penetrated the bone cortex in the guide plate group; 2 patients in the conventional group had sacroiliac screws penetrating the bone cortex without damaging blood vessels or nerves. In the guide plate group, the deviation between the virtual position and the actual position of the screw tip, the sacral foramen, and the screw entry point were (2.91±1.01), (2.10±0.74), and (1.67±0.70) mm, respectively, with an average deviation of (2.19±1.22) mm. There was no significant difference in Majeed function evaluation between the two groups at 6 months after operation (P>0.05). Conclusion The application of 3D printed faceted honeycomb guide plate in sacroiliac screw implantation for posterior pelvic ring fracture can shorten the screw implantation time, reduce the frequency of fluoroscopy and guide pin adjustment, and reduce the risk of screw penetration through the bone cortex.
Large defects of jaw caused by tumor, trauma and so on in oral and maxillofacial region lead to facial deformity, language and chewing dysfunction, which severely damage the patient’s life quality. Three-dimensional printing (3DP) is also named additive manufacturing (AM), which can print materials layer by layer to create three-dimensional objects. The complex shape of jaw defects can be accurately reconstructed using 3DP scaffold combined with image data, computer-aided-design and manufacture. It has specific advantages compared with traditional way of jaw reconstruction and has attracted much attention in the field of jaw tissue engineering recently. This article presented the progress of 3DP scaffold and its application in jaw reconstruction, providing a new idea for jaw reconstruction.
Objective To explore feasibility and effectiveness of three-dimensional (3D) printing technology in precise hepatectomy. Methods The patient was a 60-year-old woman with diagnosis of liver malignancy. The liver model was reconstructed using the IQQA Liver System (EDDA Technology, Inc. USA) based on the CT scan data. The volumes of the liver and the lesion were measured and recorded. The CT data were further digitally reconstructed by means of cloud computing and storage with RevoCloud (V1.0) Medical Imaging System. The best surgical plan was determined by the repeated virtual surgical resection with the reconstruction system, based on the corresponding resected liver volume and the remaining liver volume. Results The reconstruction of liver clearly showed that the tumor invaded the right hepatic and middle hepatic veins, as well as the anterior branch of right portal vein, which was consistent with the conclusion of CT scan. In the other hand, the right posterior branch of the portal vein was completely distributed in the segment Ⅴ and Ⅵ, while a relatively large right posterior inferior vena presented and drained segment Ⅴ and Ⅵ. The anatomic resection of segment Ⅶ, Ⅷ , and Ⅳa was completed according to the preoperative plan. The liver function kept recovering, and the patient discharged a week later. Conclusion Results of this patient show that 3D printing technology can accurately assess anatomic construction of liver and determine relationship between lesion and its surrounding tissue, which can be effectively used in precise hepatectomy.
Spinal fusion is a standard operation for treating moderate and severe intervertebral disc diseases. In recent years, the proportion of three-dimensional printing interbody fusion cage in spinal fusion surgery has gradually increased. In this paper, the research progress of molding technology and materials used in three-dimensional printing interbody fusion cage at present is summarized. Then, according to structure layout, three-dimensional printing interbody fusion cages are classified into five types: solid-porous-solid (SPS) type, solid-porous-frame (SPF) type, frame-porous-frame (FPF) type, whole porous cage (WPC) type and others. The optimization process of three-dimensional printing interbody fusion cage and the advantages and disadvantages of each type are analyzed and summarized in depth. The clinical application of various types of 3D printed interbody fusion cage was introduced and summarized later. Lastly, combined with the latest research progress and achievements, the future research direction of three-dimensional printing interbody fusion cage in molding technology, application materials and coating materials is prospected in order to provide some reference for scholars engaged in interbody fusion cage research and application.
Objective To explore the effectiveness of computer-aided technology in the treatment of primary elbow osteoarthritis combined with stiffness under arthroscopy. Methods The clinical data of 32 patients with primary elbow osteoarthritis combined with stiffness between June 2018 and December 2020 were retrospectively analyzed. There were 22 males and 10 females with an average age of 53.4 years (range, 31-71 years). X-ray film and three-dimensional CT examinations showed osteophytes of varying degrees in the elbow joint. Loose bodies existed in 16 cases, and there were 7 cases combined with ulnar nerve entrapment syndrome. The median symptom duration was 2.5 years (range, 3 months to 22.5 years). The location of bone impingement from 0° extension to 140° flexion of the elbow joint was simulated by computer-aided technology before operation and a three-dimensional printed model was used to visualize the amount and scope of impinging osteophytes removal from the anterior and posterior elbow joint to accurately guide the operation. Meanwhile, the effect of elbow joint release and impinging osteophytes removal was examined visually under arthroscopy. The visual analogue scale (VAS) score, Mayo elbow performance score (MEPS), and elbow range of motion (extension, flexion, extension and flexion) were compared between before and after operation to evaluate elbow function. Results The mean operation time was 108 minutes (range, 50-160 minutes). All 32 patients were followed up 9-18 months with an average of 12.5 months. There was no other complication such as infection, nervous system injury, joint cavity effusion, and heterotopic ossification, except 2 cases with postoperative joint contracture at 3 weeks after operation due to the failure to persist in regular functional exercises. Loose bodies of elbow and impinging osteophytes were removed completely for all patients, and functional recovery was satisfactory. At last follow-up, VAS score, MEPS score, extension, flexion, flexion and extension range of motion significantly improved when compared with preoperative ones (P<0.05). Conclusion Arthroscopic treatment of primary elbow osteoarthritis combined with stiffness using computer-aided technology can significantly reduce pain, achieve satisfactory functional recovery and reliable effectiveness.
Bone tumor surgery involves tumor resection and subsequent reconstruction. With the development of surgical technique and new material, there is a great step toward bone and joint reconstruction in bone tumor surgery. Generally speaking, there are two major reconstructive methods including bio-reconstruction and mechanical reconstruction. In addition, three-dimensional printed prosthesis has been widely applied in the field of bone tumor surgery. The short-term result is encouraged; however, long-term results and related complications are seldom reported.
ObjectiveTo investigate the accuracy of progressive three-dimensional navigation template system (abbreviated as progressive template) to assist atlas-axial pedicle screw placement. MethodsThe clinical data of 33 patients with atlas-axial posterior internal fixation surgery between May 2015 and May 2017 were retrospectively analyzed. According to the different methods of auxiliary screw placement, the patients were divided into trial group (19 cases, screw placement assisted by progressive template) and control group (14 cases, screw placement assisted by single navigation template system, abbreviated as initial navigation template). There was no significant difference in gender, age, cause of injury, damage segments, damage types, and preoperative Frankel classification between the two groups (P>0.05). The operation time and intraoperative blood loss of the two groups were compared. The safety of screw placement was evaluated on postoperative CT by using the method from Kawaguchi et al, the deviation of screw insertion point were calculated, the angular deviation of the nailing on coordinate systems XOZ, XOY, YOZ were calculated according to Peng’s method. ResultsAll patients completed the operation successfully; the operation time and intraoperative blood loss in the trial group were significantly less than those in the control group (t=–2.360, P=0.022; t=–3.006, P=0.004). All patients were followed up 12–40 months (mean, 25.3 months). There was no significant vascular injury or nerve injury aggravation. Postoperative immediate X-ray film and CT showed the dislocation was corrected. Postoperative immediate CT showed that all 76 screws were of grade 0 in the trial group, and the safety of screw placement was 100%; 51 screws were of grade 0, 3 of gradeⅠ, and 2 of gradeⅡ in the control group, and the safety of screw placement was 91.1%; there was significant difference in safety of screw placement between the two groups (χ2=7.050, P=0.030). The screw insertion point deviation and angular deviation of the nailing on XOY and YOZ planes in the trial group were significantly less than those in the control group (P<0.05). There was no significant difference in angular deviation of the nailing on XOZ between the two groups (t=1.060, P=0.290). ConclusionCompared with the initial navigation template, the progressive navigation template assisting atlas-axial pedicle screw placement to treat atlas-axial fracture with dislocation, can reduce operation time and intraoperative blood loss, improve the safety of screw placement, and match the preoperative design more accurately.
ObjectiveTo explore the effectiveness of a new point contact pedicle navigation template (referred to as “new navigation template” for simplicity) in assisting screw implantation in scoliosis correction surgery. MethodsTwenty-five patients with scoliosis, who met the selection criteria between February 2020 and February 2023, were selected as the trial group. During the scoliosis correction surgery, the three-dimensional printed new navigation template was used to assist in screw implantation. Fifty patients who had undergone screw implantation with traditional free-hand implantation technique between February 2019 and February 2023 were matched according to the inclusion and exclusion criteria as the control group. There was no significant difference between the two groups (P>0.05) in terms of gender, age, disease duration, Cobb angle on the coronal plane of the main curve, Cobb angle at the Bending position of the main curve, the position of the apical vertebrae of the main curve, and the number of vertebrae with the pedicle diameter lower than 50%/75% of the national average, and the number of patients whose apical vertebrae rotation exceeded 40°. The number of fused vertebrae, the number of pedicle screws, the time of pedicle screw implantation, implant bleeding, fluoroscopy frequency, and manual diversion frequency were compared between the two groups. The occurrence of implant complications was observed. Based on the X-ray films at 2 weeks after operation, the pedicle screw grading was recorded, the accuracy of the implant and the main curvature correction rate were calculated. ResultsBoth groups successfully completed the surgeries. Among them, the trial group implanted 267 screws and fused 177 vertebrae; the control group implanted 523 screws and fused 358 vertebrae. There was no significant difference between the two groups (P>0.05) in terms of the number of fused vertebrae, the number of pedicle screws, the pedicle screw grading and accuracy, and the main curvature correction rate. However, the time of pedicle screw implantation, implant bleeding, fluoroscopy frequency, and manual diversion frequency were significantly lower in trial group than in control group (P<0.05). There was no complications related to screws implantation during or after operation in the two groups. ConclusionThe new navigation template is suitable for all kinds of deformed vertebral lamina and articular process, which not only improves the accuracy of screw implantation, but also reduces the difficulty of operation, shortens the operation time, and reduces intraoperative bleeding.