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 compare the effectiveness between three-dimensional (3D) printed porous titanium alloy cage (3D Cage) and poly-ether-ether-ketone cage (PEEK Cage) in the posterior lumbar interbody fusion (PLIF). Methods A total of 66 patients who were scheduled to undergo PLIF between January 2018 and June 2019 were selected as the research subjects, and were divided into the trial group (implantation of 3D Cage, n=33) and the control group (implantation of PEEK Cage, n=33) according to the random number table method. Among them, 1 case in the trial group did not complete the follow-up exclusion study, and finally 32 cases in the trial group and 33 cases in the control group were included in the statistical analysis. There was no significant difference in gender, age, etiology, disease duration, surgical segment, and preoperative Japanese Orthopaedic Association (JOA) score between the two groups (P>0.05). The operation time, intraoperative blood loss, complications, JOA score, intervertebral height loss, and interbody fusion were recorded and compared between the two groups. Results The operations of two groups were completed successfully. There was 1 case of dural rupture complicated with cerebrospinal fluid leakage during operation in the trial group, and no complication occurred in the other patients of the two groups. All incisions healed by first intention. There was no significant difference in operation time and intraoperative blood loss between groups (P>0.05). All patients were followed up 12-24 months (mean, 16.7 months). The JOA scores at 1 year after operation in both groups significantly improved when compared with those before operation (P<0.05); there was no significant difference between groups (P>0.05) in the difference between pre- and post-operation and the improvement rate of JOA score at 1 year after operation. X-ray film reexamination showed that there was no screw loosening, screw rod fracture, Cage collapse, or immune rejection in the two groups during follow-up. At 3 months and 1 year after operation, the rate of intervertebral height loss was significantly lower in the trial group than in the control group (P<0.05). At 3 and 6 months after operation, the interbody fusion rating of trial group was significantly better in the trial group than in the control group (P<0.05); and at 1 year after operation, there was no significant difference between groups (P>0.05). ConclusionThere is no significant difference between 3D Cage and PEEK Cage in PLIF, in terms of operation time, intraoperative blood loss, complications, postoperative neurological recovery, and final intervertebral fusion. But the former can effectively reduce vertebral body subsidence and accelerate intervertebral fusion.
Objective To investigate the construction of a novel tissue engineered meniscus scaffold based on low temperature deposition three-dimenisonal (3D) printing technology and evaluate its biocompatibility. Methods The fresh pig meniscus was decellularized by improved physicochemical method to obtain decellularized meniscus matrix homogenate. Gross observation, HE staining, and DAPI staining were used to observe the decellularization effect. Toluidine blue staining, safranin O staining, and sirius red staining were used to evaluate the retention of mucopolysaccharide and collagen. Then, the decellularized meniscus matrix bioink was prepared, and the new tissue engineered meniscus scaffold was prepared by low temperature deposition 3D printing technology. Scanning electron microscopy was used to observe the microstructure. After co-culture with adipose-derived stem cells, the cell compatibility of the scaffolds was observed by cell counting kit 8 (CCK-8), and the cell activity and morphology were observed by dead/live cell staining and cytoskeleton staining. The inflammatory cell infiltration and degradation of the scaffolds were evaluated by subcutaneous experiment in rats. Results The decellularized meniscus matrix homogenate appeared as a transparent gel. DAPI and histological staining showed that the immunogenic nucleic acids were effectively removed and the active components of mucopolysaccharide and collagen were remained. The new tissue engineered meniscus scaffolds was constructed by low temperature deposition 3D printing technology and it had macroporous-microporous microstructures under scanning electron microscopy. CCK-8 test showed that the scaffolds had good cell compatibility. Dead/live cell staining showed that the scaffold could effectively maintain cell viability (>90%). Cytoskeleton staining showed that the scaffolds were benefit for cell adhesion and spreading. After 1 week of subcutaneous implantation of the scaffolds in rats, there was a mild inflammatory response, but no significant inflammatory response was observed after 3 weeks, and the scaffolds gradually degraded. Conclusion The novel tissue engineered meniscus scaffold constructed by low temperature deposition 3D printing technology has a graded macroporous-microporous microstructure and good cytocompatibility, which is conducive to cell adhesion and growth, laying the foundation for the in vivo research of tissue engineered meniscus scaffolds in the next step.
ObjectiveTo study clinical practical value of multimode imaging technique in precise hepatectomy for huge hepatocellular carcinoma (HCC). MethodsThe clinicopathologic data of patients with huge HCC who underwent precise hepatectomy in Yuebei People’s Hospital from Jan. 2018 to Dec. 2020 were collected. The three-dimensional (3D) reconstruction, 3D visualization, 3D printing, and augmented reality (AR) were used to guide preoperative evaluation, surgical planning, and surgical navigation. The liver function indexes, surgical mode, operative time, intraoperative bleeding, volume of resected liver, postoperative hospitalization, and complications were analyzed. ResultsThere were 23 patients in this study, including 18 males and 5 females, with (56.8±8.1) years old. The virtual tumor volume assessed by multimodal imaging technology was (865.2±165.6) mL and the virtual resected liver volume was (1 628.8±144.4) mL. The planned operations were anatomical hepatectomy in 19 patients and non-anatomical hepatectomy in 4 patients. The actual operation included 17 cases of anatomical hepatectomy and 6 cases of non-anatomical hepatectomy, which was basically consistent with the results of AR. The operative time was (298.4±74.5) min, the median hepatic blood flow blocking time was 20 min, and the intraoperative bleeding was (330.4±152.8) mL. Compared with preoperative levels, the levels of hemoglobin and albumin decreased temporarily on the first day after operation (P<0.05), and then which began to rise on the third day and basically rose to the normal range; prothrombintime, total bilirubin, alanine aminotransferase, and aspartate aminotransferase increased transiently on the first day after operation (P<0.05), then which began to decline to the normal levels. There were no serious operative complications and no perioperative death. The median follow-up time was 18 months, the tumor recurrence and metastasis occurred in 3 cases. ConclusionFrom preliminary results of this study, it could improve surgical safety and precision of hepatectomy for huge HCC by preoperative precise assessment and operation navigation in good time of multimode imaging technology.
Objective To explore the application progress and clinical value of digital technologies in the surgical treatment of ankylosing spondylitis (AS). Methods By systematically reviewing domestic and international literature, the study summarized the specific application scenarios, operational procedures, and technical advantages of digital technologies [including preoperative three-dimensional (3D) planning, intraoperative real-time navigation, robot-assisted surgery, and 3D printing] in AS surgery, and analyzed their impact on surgical accuracy, complication rates, and clinical outcomes. ResultsDigital technologies significantly improve the precision and safety of AS surgery. Preoperative 3D planning enables personalized surgical protocols; intraoperative navigation systems dynamically adjusts surgical trajectories, reducing the risk of iatrogenic injury; robot-assisted surgery can minimize human errors and enhance implant positioning accuracy; 3D-printed anatomical models and guides optimize the correction of complex spinal deformities. Furthermore, the combined applications of these technologies shorten operative time, reduce intraoperative blood loss, decrease postoperative complications (e.g., infection, nerve injury), and accelerate functional recovery.ConclusionThrough multidimensional integration and innovation, digital technologies provide a precise and minimally invasive solution for AS surgical treatment. Future research should focus on their synergy with biomaterials and intelligent algorithms to further refine surgical strategies and improve long-term prognosis.
Three-dimensional (3D) printing, an emerging rapid prototyping technology, has been widely used in biomedical field. 3D printing was originally used to construct the visualization models and molds in medicine. With the development of 3D printing in biomedical field, the technology was gradually applied in complex tissue regeneration and organ reconstruction. Artificial tissues and organs obtained by 3D printing are expected to be used for organ transplantation, new drug development and drug toxicity evaluation in the field of medicine and health care research. This paper describes the individualized application of 3D printing technology in liver surgery and introduces the research progress of 3D bioprinting technology in liver transplantation, drug metabolism and hepatotoxicity evaluation, and prospects its future development trend to provide a reference for further study.
ObjectiveTo investigate the effectiveness of three-dimensional (3D) navigation template in the adult cubitus varus osteotomy.MethodsBetween April 2013 and September 2015, 17 patients with cubitus varus were admitted. There were 6 males and 11 females, aged from 19 to 38 years, with an average age of 26.9 years. There were 10 cases of left elbow joints and 7 cases of right elbow joints. The disease duration was 9-30 years (mean, 18 years). Based on the preoperative X-ray film, the humerus-elbow-wrist (HEW) angle was (−13.2 ±3.3)°, the anteversion angle was (−10.5±2.3)°. The preoperative range of motion (ROM) of flexion was (127.3±7.3)° and ROM of extension was (−10.0±2.5)°. Based on the CT 3D reconstruction, the osteotomy navigation template was designed and printed by 3D printing technique. The cubitus varus osteotomy was assisted by 3D navigation template. The postoperative HEW angle, anteversion angle, and ROMs of the elbow joints of both sides were measured. The elbow function was evaluated based on the Oppenheim elbow function score at 1 year after operation.ResultsAll cubitus varus osteotomies succeeded with the assist of 3D navigation template. All incisions healed by first intention. All patients were followed up 12-15 months (mean, 13 months). X-ray films showed that all osteotomies healed after 9-12 weeks (mean, 11 weeks). At 1 year after operation, the HEW angle was (9.7±1.9)°, the anteversion angle was (20.7±4.3)°, the ROM was (2.6±3.5)° in extension and (139.2±4.8)° in flexion of affected side. The HEW angle, anteversion angle, and ROMs significantly increased compared with preoperative values (P<0.05). And there was no significant difference between affected and normal elbow joints (P>0.05). The elbow functions were excellent in 13 cases and good in 4 cases based on the Oppenheim elbow function score at 1 year after operation. There was no complication such as the nerve injury or osteomyositis of elbow joint during follow-up. ConclusionThe 3D navigation template can provide a personalized and precise osteotomy treatment for adult cubitus varus deformity and obtain a satisfactory effectiveness.
Objective To investigate the effectiveness of using 3 hollow compression screws combined with 1 screw off-axis fixation under the guidance of three-dimensional (3D) printed guide plate with mortise-tenon joint structure (mortise-tenon joint plate) for the treatment of Pauwels type Ⅲ femoral neck fractures. Methods A clinical data of 78 patients with Pauwels type Ⅲ femoral neck fractures, who were admitted between August 2022 and August 2023 and met the selection criteria, was retrospectively analyzed. The operations were assisted with mortise-tenon joint plates in 26 cases (mortise-tenon joint plate group) and traditional guide plates in 28 cases (traditional plate group), and without guide plates in 24 cases (control group). There was no significant difference in the baseline data of gender, age, body mass index, cause of injury, and fracture side between groups (P>0.05). The operation time, intraoperative blood loss, frequency of intraoperative fluoroscopy, incision length, incidence of postoperative deep vein thrombosis of lower extremity, pain visual analogue scale (VAS) score at 1 week after operation, and Harris score of hip joint at 3 months after operation were recorded and compared. X-ray re-examination was taken to check the quality of fracture reduction, fracture healing, and the shortening length of the femoral neck at 3 months after operation, and the incidences of internal fixation failure and osteonecrosis of the femoral head during operation. Results Compared with the control group, the operation time, intraoperative blood loss, and frequency of intraoperative fluoroscopy reduced in the two plate groups, and the quality of fracture reduction was better, but the incision was longer, and the differences were significant (P<0.05). The operation time and intraoperative blood loss were significantly higher in the traditional plate group than in the mortise-tenon joint plate group (P<0.05), the incision was significantly longer (P<0.05); and the difference in fracture reduction quality and the frequency of intraoperative fluoroscopy was not significant between two plate groups (P>0.05). There was 1 case of deep vein thrombosis of lower extremity in the traditional plate group and 1 case in the control group, while there was no thrombosis in the mortise-tenon joint plate group. There was no significant difference in the incidence between groups (P>0.05). All patients were followed up 12-15 months (mean, 13 months). There was no significant difference in VAS score at 1 week and Harris score at 3 months between groups (P>0.05). Compared with the control group, the fracture healing time and the length of femoral neck shortening at 3 months after operation were significantly shorter in the two plate groups (P<0.05). There was no significant difference between the two plate groups (P>0.05). There was no significant difference in the incidences of non-union fractures, osteonecrosis of the femoral head, or internal fixation failure between groups (P>0.05). Conclusion For Pauwels type Ⅲ femoral neck fractures, the use of 3D printed guide plate assisted reduction and fixation can shorten the fracture healing time, reduce the incidence of postoperative complications, and be more conducive to the early functional exercise of the affected limb. Compared with the traditional guide plate, the mortise-tenon joint plate can reduce the intraoperative bleeding and shorten the operation time.
ObjectiveTo investigate the short-term effectiveness of three-dimensional (3D) printed trabecular metal pads for Paprosky type Ⅲ acetabular defect in hip revision.MethodsBetween August 2014 and December 2015, the 3D printed trabecular metal pads were used to repair Paprosky type Ⅲ acetabular defects and reconstruct the annular structure of the acetabulums in 5 cases of primary hip revision. There were 3 males and 2 females, aged from 50 to 72 years, with an average age of 66 years. The time from initial replacement to revision was 10 to 18 years, with an average of 14.4 years. The types of prostheses in primary replacement were non-cemented in 3 cases and cemented in 2 cases. The types of acetabular bone defects were Paprosky type ⅢA in 3 cases and Paprosky type ⅢB in 2 cases. The preoperative Harris score was 34.23±11.67. The height of rotation center of affected hip was (38.17±8.87) mm and the horizontal position was (35.62±9.12) mm.ResultsThe operation time was 120-180 minutes, with an average of 142 minutes. The intraoperative bleeding volume was 800-1 700 mL, with an average of 1 100 mL. Five patients were followed up 18-24 months (mean, 21 months). At last follow-up, the Harris score was 79.82±8.70, which was significantly higher than that before operation (t=16.991, P=0.000). At 1 week after operation, the abduction angle of acetabular cup was 38-42° (mean, 39.4 °) and the anteversion angle was 13-18 ° (mean, 14.6°). The height and horizontal position of rotation center of affected hip were (22.08±8.33) mm and (29.03±6.28) mm, respectively, showing significant differences when compared with those before operation (P<0.05); there was no significant difference when compared with those of healthy hip [(28.62±7.73), (27.29±4.22) mm] (P>0.05). During the follow-up, there was no complication such as prosthesis loosening, dislocation, or periprosthetic fracture.ConclusionIn hip revision, 3D printed trabecular metal pads can repair Paprosky type Ⅲ acetabular defect, reconstruct the structure of acetabulum, provide a stable supporting structure for the acetabular cup, reconstruct the relatively normal rotation center of the hip joint, avoid iatrogenic bone loss, and achieve satisfactory functional recovery of the hip. The long-term effectiveness needs further follow-up.
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.