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.
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.
In order to address the problem of traditional dolphin adjuvant therapy such as high cost and its limitation in time and place, this paper introduces a three-dimensional virtual dolphin adjuvant therapy system based on virtual reality technology. By adopting Oculus wearable three-dimensional display, the system combined natural human-computer interaction based on Leap Motion with high-precision gesture recognition and cognitive training, and achieved immersive three-dimensional interactive game for child rehabilitation training purposes. The experimental data showed that the system can effectively improve the cognitive and social abilities of those children with autism spectrum disorder, providing a useful exploration for the rehabilitation of those children.
Objective To review the research progress of in-situ three dimensional (3D) bio-printing technology in the repair of bone and cartilage injuries. Methods Literature on the application of in-situ 3D bio-printing technology to repair bone and cartilage injuries at home and abroad in recent years was reviewed, analyzed, and summarized. Results As a new tissue engineering technology, in-situ 3D bio-printing technology is mainly applied to repair bone, cartilage, and skin tissue injuries. By combining biomaterials, bioactive substances, and cells, tissue is printed directly at the site of injury or defect. At present, the research on the technology mainly focuses on printing mode, bio-ink, and printing technology; the application research in the field of bone and cartilage mainly focuses on pre-vascularization, adjusting the composition of bio-ink, improving scaffold structure, printing technology, loading drugs, cells, and bioactive factors, so as to promote tissue injury repair. Conclusion Multiple animal experiments have confirmed that in-situ 3D bio-printing technology can construct bone and cartilage tissue grafts in a real-time, rapid, and minimally invasive manner. In the future, it is necessary to continue to develop bio-inks suitable for specific tissue grafts, as well as combine with robotics, fusion imaging, and computer-aided medicine to improve printing efficiency.
Objective To design a new type of three-dimensional honeycomb guide for percutaneous cannulated screw placement in femoral neck fracture and evaluate its effectiveness. Methods The clinical data of 40 patients with femoral neck fracture who met the selection criteria between June 2019 and December 2020 were retrospectively analyzed. According to different intraoperative positioning methods, they were divided into control group (20 cases, free hand positioning screws) and study group (20 cases, new guide assisted positioning screws). There was no significant difference in gender, age, side, cause of injury, Garden classification, and time from injury to operation between the two groups (P>0.05). The operation time, fluoroscopy times, guide needle puncture times, and fracture healing time of the two groups were recorded. The hip function was evaluated by Harris score at last follow-up. At immediate after operation, the following imaging indexes were used to evaluate the accuracy of screw implantation distribution: screw spacing, screw coverage area, distance from screw to cervical cortex, parallelism between screws, and screw to cervical axial deviation. Results All operations were successfully completed, and the guide needle did not penetrate the femoral neck cortex. There was no significant difference in operation time and fluoroscopy times between the two groups (P>0.05); the guide needle puncture times in the study group was significantly less than that in the control group (t=8.209, P=0.000). Imaging detection at immediate after operation showed that the screw spacing and screw coverage area in the study group were significantly greater than those in the control group (P<0.05); the distance from screw to cervical cortex, parallelism between screws, and screw to cervical axial deviation were significantly smaller than those in the control group (P<0.05). All patients were followed up 7-25 months, with an average of 19.3 months. There was no significant difference in follow-up time between the two groups (t=?0.349, P=0.729). There were 2 cases of fracture nonunion in the control group and 1 case in the study group, and the other fractures completely healed. One case of osteonecrosis of the femoral head occurred in the control group. During the follow-up, there was no complication such as vascular and nerve injury, venous thrombosis, screw penetration, withdrawal, breakage, and refracture, etc. There was no significant difference in fracture healing time and Harris score at last follow-up between the two groups (P>0.05). ConclusionThe new three-dimensional honeycomb guide has the advantages of simple structure and convenient use. It can reduce the puncture times of the guide needle and effectively improve the accuracy distribution of cannulated screw implantation.
ObjectiveTo establish a model of three-dimensional (3-D) cephalometric analysis to study dentomaxillofacial deformities. MethodsBetween January 2012 and October 2013,15 patients with dentomaxillofacial deformities were treated using 3-D cephalometric analysis in orthognathic surgery plan.There were 7 males and 8 females with an average age of 23.6 years (range,17-37 years),including 4 cases of mandibular protrusion with maxillary deficiency,4 cases of maxillary protrusion with mandibular deficiency,2 cases of long face syndrome,and 5 cases of facial asymmetry.CT images were reconstructed by Mimics software.The anatomical landmarks were located,the reference planes and analysis planes were defined and the 3-D coordinate was established.The distance and degree between landmarks and analysis planes which defined in the measure project were measured. ResultsBased on the 3-D CT quantitative analysis methods,cephalometric analysis project was defined in the 3-D coordinate.3-D cephalometric analysis provided a convenient and precise method for the clinical measurement of dentomaxillofacial morphology,and reduce the time in preoperation analysis. ConclusionThe model of 3-D CT cephalometric analysis can provide precise information in the diagnosis and treatment planning of orthognathic surgery.
Objective To compare the reduction qualities of three-dimensional visible technique without fluoroscopy and two-dimensional fluoroscopy for unstable pelvic fractures during operations. Methods The clinical data of 40 patients with unstable pelvic fractures, who met the selection criteria in three clinical centers between June 2021 and September 2022, were retrospectively analyzed. According to the reduction methods, the patients were divided into two groups. Twenty patients in trial group were treated with unlocking closed reduction system combined with three-dimensional visible technique without fluoroscopy; 20 patients in control group with unlocking closed reduction system under two-dimensional fluoroscopy. There was no significant difference in the gender, age, injury mechanism, Tile type of fracture, Injury Severity Score (ISS), and the time between injury to operation between the two groups (P>0.05). The qualities of fracture reduction according to the Matta criteria, operative time, intraoperative blood loss, fracture reduction time, times of fluoroscopy, and System Usability Scale (SUS) score were recorded and compared. Results All operations were successfully completed in both groups. According to the Matta criteria, the qualities of fracture reduction were rated as excellent in 19 patients (95%) in trial group, which was better than that in the control group (13 cases, 65%), with a significant difference (χ2=3.906, P=0.048). The operative time and intraoperative blood loss had no significant differences between the two groups (P>0.05). The fracture reduction time and times of fluoroscopy were significantly less in trial group than in control group (P<0.05), and SUS score in trial group was significantly higher in trial group than in control group (P<0.05). ConclusionCompared to using unlocking closed reduction system under two-dimensional fluoroscopy, three-dimensional visible technique without fluoroscopy can significantly improve the reduction quality of unstable pelvic fractures without prolonging the operative time, and is valuable to reduce iatrogenic radiation exposure for patients and medical workers.
In this article, we introduce the principle, describe the utilization and discuss the future development of three-dimensional printing technology for manufacturing artificial organs.
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.
ObjectiveTo investigate the effectiveness of percutaneous double-segment lengthened sacroiliac screws internal fixation assisted by three-dimensional (3D) navigation technology in treatment of Denis type Ⅱ and Ⅲ sacral fractures. Methods A clinical data of 45 patients with the Denis type Ⅱ and Ⅲ sacral fractures admitted between January 2017 and May 2020 was retrospectively analyzed. There were 31 males and 14 females, with an average age of 48.3 years (range, 30-65 years). The pelvic fractures were all high energy injuries. According to the Tile classification standard, there were 24 cases of type C1, 16 cases of type C2, and 5 cases of type C3. The sacral fractures were classified as Denis type Ⅱ in 31 cases and type Ⅲ in 14 cases. The interval between injury and operation was 5-12 days (mean, 7.5 days). The lengthened sacroiliac screws were implanted in S1 and S2 segments respectively under the assistance of 3D navigation technology. The implantation time of each screw, the intraoperative X-ray exposure time, and the occurrence of surgical complications were recorded. After operation, the imaging reexamination was used to evaluate the screw position according to Gras standard and the reduction quality of sacral fractures according to Matta standard. At last follow-up, the pelvic function was scored with Majeed scoring standard. Results The 101 lengthened sacroiliac screws were implanted with the assisting of 3D navigation technology. The implantation time of each screw was 37.3 minutes on average (range, 30-45 minutes), and the X-ray exposure time was 46.2 seconds on average (range, 40-55 seconds). All patients had no neurovascular or organ injury. All incisions healed by first intention. The quality of fracture reduction was evaluated according to Matta standard as excellent in 22 cases, good in 18 cases, and fair in 5 cases, and the excellent and good rate was 88.89%. The screw position was evaluated according to Gras standard as excellent in 77 screws, good in 22 screws, and poor in 2 screws, and the excellent and good rate was 98.02%. All patients were followed up 12-24 months (mean, 14.6 months). All fractures healed and the healing time was 12-16 weeks (mean, 13.5 weeks). Pelvic function was evaluated according to Majeed scoring standard as excellent in 27 cases, good in 16 cases, fair in 2 cases, and the excellent and good rate was 95.56%. Conclusion Percutaneous double-segment lengthened sacroiliac screws internal fixation for the treatment of Denis type Ⅱ and Ⅲ sacral fractures is minimally invasive and effective. With the assistance of 3D navigation technology, the screw implantation is accurate and safe.