With the development of three-dimensional (3D) printing technology, more and more researches have focused on its application in the region of intervertebral fusion materials; the prospects are worth looking forward to. This article reviews the researches about 3D printing technology in spinal implants, and summarizes the materials and printing technology applied in the field of spinal interbody fusion, and the shortcomings in the current research and application. With the rapid development of 3D printing technology and new materials, more and more 3D printing spinal interbodies will be developed and used clinically.
More and more relevant research results show that anatomical segmentectomy has the same effect as traditional lobectomy in the surgical treatment of early-stage non-small cell lung cancer (diameter<2.0 cm). Segmentectomy is more difficult than lobotomy. Nowadays, with the promotion of personalization medicine and precision medicine, three-dimensional technique has been widely applied in the medical field. It has advantages such as preoperative simulation, intraoperative positioning, intraoperative navigation, clinical teaching and so on. It plays a key role in the discovery of local anatomical variation of pulmonary segment. This paper reviewed the clinical application of three-dimensional technique and briefly described the clinical application value of this technique in segmentectomy.
ObjectiveTo analyze the clinical outcomes of 3D-printing assisting minimally invasive fixation of calcaneal fractures. MethodsThe study included 12 patients who were diagnosed with calcaneal fractures between October 2014 and May 2015. Using a real-size 3D-printed calcaneus model, the calcaneal locking plate could be preshaped before the operation and used with a minimally invasive approach to achieve rigid plate fixation just as with the lateral approach. Complications and surgery time were recorded and functional results were evaluated using the American Orthopaedic Foot Society ankle-metapedes score (AOFAS). The reduction of fracture was evaluated using the Bohler angle and Gissane angle. ResultsThere was no relevant postoperative complications. All fractures got bone union. The mean postoperative Bohler angle was (29.4±6.1) ° and the mean postoperative Gissane angle was (121.4±12.6) °. The difference in Bohler angle and calcaneal Gissane angle before and after the surgery was significant (P ＜ 0.01) . The mean postoperative AOFAS score was 75.2±5.4, and the fine/excellent rate was 83.3%. ConclusionWe believe this novel technique can be useful for the operative treatment of displaced intra-articular calcaneal fractures.
ObjectiveTo manufacture a polycaprolactone (PCL)/type Ⅰ collagen (COL Ⅰ) tissue engineered meniscus scaffold (hereinafter referred to as PCL/COL Ⅰ meniscus scaffold) by three-dimensional (3D) printing with low temperature deposition technique and to study its physicochemical properties.MethodsFirst, the 15% PCL/4% COLⅠ composite solution and 15% PCL simple solution were prepared. Then, 15% PCL/4% COL Ⅰmeniscus scaffold and 15% PCL meniscal scaffold were prepared by using 3D printing with low temperature deposition techniques. The morphology and microstructure of the scaffolds were observed by gross observation and scanning electron microscope. The compression modulus and tensile modulus of the scaffolds were measured by biomechanical test. The components of the scaffolds were analyzed by Fourier transform infrared spectroscopy (FTIR). The contact angle of the scaffold surface was measured. The meniscus cells of rabbits were cultured with the two scaffold extracts and scaffolds, respectively. After cultured, the cell proliferations were detected by cell counting kit 8 (CCK-8), and the normal cultured cells were used as controls. Cell adhesion and growth of scaffold-cell complex were observed by scanning electron microscope.ResultsAccording to the gross and scanning electron microscope observations, two scaffolds had orientated 3D microstructures and pores, but the surface of the PCL/COLⅠ meniscus scaffold was rougher than the PCL meniscus scaffold. Biomechanical analysis showed that the tensile modulus and compression modulus of the PCL/COL Ⅰ meniscus scaffold were not significantly different from those of the PCL meniscus scaffold (P>0.05). FTIR analysis results showed that COL Ⅰ and PCL were successful mixed in PCL/ COL Ⅰ meniscus scaffolds. The contact angle of PCL/COLⅠ meniscus scaffold [(83.19±7.49)°] was significantly lower than that of PCL meniscus scaffold [(111.13±5.70)°] (t=6.638, P=0.000). The results of the CCK-8 assay indicated that with time, the number of cells cultured in two scaffold extracts showed an increasing trend, and there was no significant difference when compared with the control group (P>0.05). Scanning electron microscope observation showed that the cells attached on the PCL/ COL Ⅰ meniscus scaffold more than that on the PCL scaffold.ConclusionPCL/COLⅠmeniscus scaffolds are prepared by 3D printing with low temperature deposition technique, which has excellent physicochemical properties without cytotoxicity. PCL/COLⅠmeniscus scaffold is expected to be used as the material for meniscus tissue engineering.
Objective To manufacture a poly (lactic-co-glycolic acid) (PLGA) scaffold by low temperature deposition three-dimensional (3D) printing technology, prepare a PLGA/decellularized articular cartilage extracellular matrix (DACECM) cartilage tissue engineered scaffold by combining DACECM, and further investigate its physicochemical properties. Methods PLGA scaffolds were prepared by low temperature deposition 3D printing technology, and DACECM suspensions was prepared by modified physical and chemical decellularization methods. DACECM oriented scaffolds were prepared by using freeze-drying and physicochemical cross-linking techniques. PLGA/DACECM oriented scaffolds were prepared by combining DACECM slurry with PLGA scaffolds. The macroscopic and microscopic structures of the three kinds of scaffolds were observed by general observation and scanning electron microscope. The chemical composition of DACECM oriented scaffold was analyzed by histological and immunohistochemical stainings. The compression modulus of the three kinds of scaffolds were measured by biomechanical test. Three kinds of scaffolds were embedded subcutaneously in Sprague Dawley rats, and HE staining was used to observe immune response. The chondrocytes of New Zealand white rabbits were isolated and cultured, and the three kinds of cell-scaffold complexes were prepared. The growth adhesion of the cells on the scaffolds was observed by scanning electron microscope. Three kinds of scaffold extracts were cultured with L-929 cells, the cells were cultured in DMEM culture medium as control group, and cell counting kit 8 (CCK-8) was used to detect cell proliferation. Results General observation and scanning electron microscope showed that the PLGA scaffold had a smooth surface and large pores; the surface of the DACECM oriented scaffold was rough, which was a 3D structure with loose pores and interconnected; and the PLGA/DACECM oriented scaffold had a rough surface, and the large hole and the small hole were connected to each other to construct a vertical 3D structure. Histological and immunohistochemical qualitative analysis demonstrated that DACECM was completely decellularized, retaining the glycosaminoglycans and collagen typeⅡ. Biomechanical examination showed that the compression modulus of DACECM oriented scaffold was significantly lower than those of the other two scaffolds (P<0.05). There was no significant difference between PLGA scaffold and PLGA/DACECM oriented scaffold (P>0.05). Subcutaneously embedded HE staining of the three scaffolds showed that the immunological rejections of DACECM and PLGA/DACECM oriented scaffolds were significantly weaker than that of the PLGA scaffold. Scanning electron microscope observation of the cell-scaffold complex showed that chondrocytes did not obviously adhere to PLGA scaffold, and a large number of chondrocytes adhered and grew on PLGA/DACECM oriented scaffold and DACECM oriented scaffold. CCK-8 assay showed that with the extension of culture time, the number of cells cultured in the three kinds of scaffold extracts and the control group increased. There was no significant difference in the absorbance (A) value between the groups at each time point (P>0.05). Conclusion The PLGA/DACECM oriented scaffolds have no cytotoxicity, have excellent physicochemical properties, and may become a promising scaffold material of tissue engineered cartilage.
Objective To assess the application value of 3-dimensional(3D) printing technology in surgical treatment for congenital tracheal stenosis. Methods We retrospectively analyzed the clinical data of preoperative diagnosis, intra-operative decision-making and postoperative follow-up of four children with congenital tracheal stenosis under the guidance of 3D printing in our hospital between February 2013 and May 2014. There were 3 males and 1 female aged 23.0±7.1 months. Among them, two children were with pulmonary artery sling, one with ventricular septal defect, and the other one with tetralogy of Fallot. The airway stenosis was diagnosed preoperatively by chest CT scan and 3D printing tracheal models, and was confirmed by the help of bronchoscopy under anesthesia. During operation the associated cardiac malformation was corrected firstly under extracorporeal circulation followed by tracheal malformation remedy. The design and implementation of tracheal operation plans were guided by the shape and data from 3D printing trachea models. There were two patients with long segment of tracheal stenosis who received slide anastomosis. And the other two patients were characterized with tracheal bronchus, one of which combined ostial stenosis of right bronchial performed extensive slide anastomosis, and the other one performed end to end anastomosis. Results All the children’s preoperative 3D printing trachea models were in accord with bronchoscopy and intra-operative exploration results. Intra-operative bronchoscopy confirmed that all tracheal stenosis cured completely. All anastomotic stomas were of integrity, and all the luminals were fluent. There was no operative death or no serious complication. During 1-2 years follow-up, all patients breathed smoothly and their airways were of patency by postoperative 3D printing trachea model. Conclusion 3D printing can provide a good help to congenital tracheal stenosis in preoperative diagnosis, the design of operation plan, intra-operative decision-making and manipulation, which can improve the operation successful rate of tracheal stenosis.
Mitral valve disease is the most common cardiac valve disease. The main treatment of mitral valve disease is surgery or interventional therapy. However, as the anatomy of mitral valve is complicated, the operation is particularly difficult. As a result, it requires sophisticated experiences for surgeons. Three-dimensional (3D) printing technology can transform two-dimensional medical images into 3D solid models. So it can provide clear spatial anatomical information and offer safe and personalized treatment for the patients by simulating surgery process. This article reviews the applications of 3D printing technology in the treatment of mitral valve disease.
ObjectiveTo investigate the short-term effectiveness of three-dimensional (3D) printing personalized prosthesis in the treatment of giant cell tumor of bone around knee joint.MethodsA clinical data of 9 patients with giant cell tumor of bone around knee joints and met the inclusive criteria between May 2014 and August 2017 was retrospectively analysed. There were 4 males and 5 females, with an average age of 35.8 years (range, 24-50 years). The lesion located at the distal femur in 4 cases and at the proximal tibia in 5 cases. The disease duration was 5-25 months (mean, 12.9 months). According to Campanacci grading, there were 2 patients of grade Ⅰ and 7 of grade Ⅱ. The 3D printing personalized prosthesis was designed based on the CT scanning and 3D reconstruction prepared before operation. All patients were treated with the tumor resection and 3D printing personalized prosthesis reconstruction. The radiological examination was taken to observe the tumor recurrence and the Musculoskeletal Tumor Society 1993 (MSTS93) score was used to evaluate the knee function.ResultsAll operations were successful and all incisions healed by first intention without early complications. All patients were followed up 24-40 months (mean, 31.2 months). At last follow-up, no complication such as pain, pathological fracture, prosthesis loosening, or tumor recurrence occurred. The MSTS93 score was 20-29 (mean, 24.7). The knee function was rated as excellent in 6 cases and good in 3 cases, with the excellent and good rate of 100%. ConclusionFor giant cell tumor of bone around knee joint, 3D printing personalized prosthesis has the advantages of bio-fusion with host bone, mechanical stability, good joint function, and ideal short-term effectiveness. But the middle- and long-term effectiveness still need to be further observed.
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.
In recent years, 3D printing technology, as a new material processing technology, can precisely control the macroscopic and microstructure of biological scaffolds and has advantages that traditional manufacturing methods cannot match in the manufacture of complex bone repair scaffolds. Magnesium ion is one of the important trace elements of the human body. It participates in many physiological activities of the body and plays a very important role in maintaining the normal physiological function of the organism. In addition, magnesium ions also have the characteristics of promoting the secretion of osteogenic proteins by osteoblasts and osteogenic differentiation of mesenchymal stem cells. By combining with 3D printing technology, more and more personalized magnesium-based biological scaffolds have been produced and used in bone regeneration research in vivo and in vitro. Therefore, this article reviews the application and research progress of 3D printing magnesium-based biomaterials in the field of bone regeneration and repair.