Reconstructing three-dimensional (3D) models from two-dimensional (2D) images is necessary for preoperative planning and the customization of joint prostheses. However, the traditional statistical modeling reconstruction shows a low accuracy due to limited 3D characteristics and information loss. In this study, we proposed a new method to reconstruct the 3D models of femoral images by combining a statistical shape model with Laplacian surface deformation, which greatly improved the accuracy of the reconstruction. In this method, a Laplace operator was introduced to represent the 3D model derived from the statistical shape model. By coordinate transformations in the Laplacian system, novel skeletal features were established and the model was accurately aligned with its 2D image. Finally, 50 femoral models were utilized to verify the effectiveness of this method. The results indicated that the precision of the method was improved by 16.8%–25.9% compared with the traditional statistical shape model reconstruction. Therefore, the method we proposed allows a more accurate 3D bone reconstruction, which facilitates the development of personalized prosthesis design, precise positioning, and quick biomechanical analysis.
Objective To summarize the application progress of three-dimensional (3D) printed metal prosthesis in joint surgery. Methods The related literature was extensively reviewed. The effectiveness of 3D printed metal prosthesis in treatment of joint surgery diseases were discussed and summarized, including the all key issues in prosthesis transplantation such as prosthesis stability, postoperative complications, bone ingrowth, etc. Results 3D printed metal prosthesis has good matching degree, can accurately reconstruct and restore joint function, reduce operation time, and achieve high patient satisfaction in short- and medium-term follow-up. Its application in joint surgery has made good progress. Conclusion The personalized microporous structure prostheses of different shapes produced by 3D printing can solve the problem of poor personalized matching of joints for special patients existing in traditional prostheses. Therefore, 3D printing technology is full of hope and will bring great potential to the reform of orthopedic practice in the future.
With the developing of three-dimensional (3D) printing technology, it is widely used in the treatment of bone tumors in the clinical orthopedics. Because of the great individual differences in the location of bone tumor, resection and reconstruction are difficult. Based on 3D printing technology, the 3D models can be prepared to show the anatomical part of the disease, so that the surgeons can create a patient-specific operational plans based on better understand the local conditions. At the same time, preoperative simulation can also be carried out for complex operations and patient-specific prostheses can be further designed and prepared according to the location and size of tumor, which may have more advantages in adaptability. In this paper, the domestic and international research progress of 3D printing technology in the treatment of limb bone tumors in recent years were reviewed and summarized.
Objective To investigate the cl inical directive significance of three-dimensional reconstruction of CT in treating mandibular angle hypertrophy. Methods Between March 2009 and January 2011, 18 patients with mandibular angle hypertrophy were treated using the three-dimensional reconstruction technology of CT. All patients were female, aged20-36 years with an average of 25 years. Eighteen patients included: 14 single mandibular angle hypertrophy, 3 mandibular angle hypertrophy with masseter hypertrophy, and 1 mandibular angle hypertrophy with bilateral asymmetry; 6 cases of ptosis of mandibular angle, 9 cases of prominent mandibular angle, and 3 cases of introversive mandibular angle. According to the types of mandibular angle hypertrophy, the surgical methods could be correctly chosen. The procedure was planned and simulated; the osteotomy l ine was marked and the osteotomy was measured on the workstations of three-dimensional reconstruction. Results No fracture of mandible occurred in the operation. Facial nerve temporary attack occurred in 1 case and recovered at 3 months after operation. All patients were followed up 6-12 months (mean, 7.6 months). After 6 months of operation, the effectiveness was satisfactory in 15 cases, basically satisfactory in 2 cases, and unsatisfactory in 1 case (bilateral asymmetry). Conclusion Based on three-dimensional reconstruction technology of CT, surgical design performed on the model will promote the accuracy of operation. Basically symmetrical appearances can be achieved with satisfactory results.
ObjectiveTo investigate the effectiveness of digital three-dimensional (3D) printing osteotomy guide plate assisted total knee arthroplasty (TKA) in treatment of knee osteoarthritis (KOA) patients with femoral internal implants. Methods The clinical data of 55 KOA patients who met the selection criteria between July 2021 and October 2023 were retrospectively analyzed. Among them, 26 cases combined with femoral implants were treated with digital 3D printing osteotomy guide plate assisted TKA (guide plate group), and 29 cases were treated with conventional TKA (control group). There was no significant difference in gender, age, body mass index, side, Kellgren-Lawrence classification, preoperative visual analogue scale (VAS) score, Hospital for Special Surgery (HSS) knee score, knee range of motion, and other baseline data between the two groups (P>0.05). The operation time, intraoperative blood loss, incision length, postoperative first ambulation time, surgical complications; VAS score, knee HSS score, knee range of motion before operation, at 1 week and 3 months after operation, and at last follow-up; distal femoral lateral angle, proximal tibial medial angle, hip-knee-ankle angle and other imaging indicators at last follow-up were recorded and compared between the two groups. ResultsThe operation time, incision length, intraoperative blood loss, and postoperative first ambulation time in the guide plate group were significantly lower than those in the control group (P<0.05). In the control group, there were 1 case of incision rupture and bleeding and 1 case of lower limb intermuscular venous thrombosis, which was cured after symptomatic treatment. There was no complication such as neurovascular injury, incision infection, or knee prosthesis loosening in both groups. Patients in both groups were followed up 12-26 months, with an average of 16.25 months. The VAS score, HSS score, and knee range of motion improved at each time point after operation in both groups, and further improved with time after operation, the differences were significant (P<0.05). The above indicators in the guide plate group were significantly better than those in the control group at 1 week and 3 months after operation (P<0.05), and there was no significant difference between the two groups at last follow-up (P>0.05). At last follow-up, the distal femoral lateral angle, the proximal tibial medial angle, and the hip-knee-ankle angle in the guide plate group were significantly better than those in the control group (P<0.05). Conclusion The application of digital 3D printing osteotomy guide plate assisted TKA in the treatment of KOA patients with femoral implants can simplify the surgical procedures, overcome limitations of conventional osteotomy guides, reduce surgical trauma, achieve individualized and precise osteotomy, and effectively restore lower limb alignment and knee joint function.
【Abstract】ObjectiveTo evaluate the value of MR imaging with a contrast-enhanced multi-phasic isotropic volumetric interpolated breath-hold examination (VIBE) in diagnosis of primary liver carcinoma. MethodsThirty-two consecutive patients with surgical-pathologically confirmed 42 foci of primary carcinoma of liver underwent comprehensive MR examination of the upper abdomen, routine two-dimensional (2D) T1WI and T2WI images were acquired before administration of Gd-DTPA for contrast enhancement. Then, contrast-enhanced multi-phasic VIBE was acquired followed by 2D T1WI images. The lesion appearances on hepatic arterial, portal venous and equilibrium phases of VIBE sequence were carefully observed along with delineation of hepatic arterial and portal venous structures. The lesion detection rates and lesion characterization ability were compared among various MR sequences. Results33(78.6%), 30(71.4%), 38(90.5%) and 42(100%) foci were displayed respectively on T2WI, non-enhanced T1WI, enhanced T1WI and enhanced 3D-VIBE images (P＜0.05). The hepatic arterial anatomy of 30 patients （93.8%） and the portal venous structure of 31 patients （96.9%） were clearly depicted on enhanced 3D-VIBE images. Using MIP and MPR reconstruction techniques, the feeding arteries of 14 foci and draining vein of 12 foci were clearly displayed.ConclusionHigh-quality 3D-VIBE images are not only better than 2D images in lesion detection and characterization for primary liver carcinoma, but also able to provide much more information about hepatic vascular anatomy.
Objective To investigate the effects of in-vitro monolayer culture and three-dimensional (3-D) alginate microsphere culture on the differentiation of normal human nucleus pulposus cells (NPCs), and to discuss the regulatory mechanism of restoring the phenotype of dedifferentiated NPCs by culturing resveratrol (RES) in 3-D alginate microsphere. Methods Normal human nucleus pulposus tissues were harvested for culture and identification of NPCs from 6 patients with burst lumbar vertebra fracture. NPCs at passages 1, 3, 5, and 7 in the in-vitro monolayer culture were harvested to observe the morphology, cell aging, and proteoglycan expression. The cell proliferation rates of NPCs at passage 1 in-vitro in monolayer culture and in 3-D alginate microsphere culture were detected. NPCs at passage 7 were randomly divided into 3-D alginate microsphere control group (group A), RES group (group B), silent mating type information regulation 2 homolog 1 (SIRT1)- small interfering RNA (siRNA) + RES group (group C), and negative control-siRNA + RES group (group D); and NPCs in the in-vitro monolayer culture was monolayer control group (group E). After corresponding treatment, Western blot was used for determining the protein expressions of SIRT1, Aggrecan, and collagen type II; real-time fluorescence quantitative PCR was used for detecting SIRT1 mRNA expression. Results The cultured cells were identified to be NPCs. Morphological observation, senescence-associated β-galactosidase (SA-β-gal) staining, and toluidine blue staining showed that dedifferentiation of normal NPCs tended to occur under continuous in-vitro monolayer culture, which was more obvious with increase of passage number. NPCs in 3-D alginate microsphere culture showed significantly lower proliferation rate than NPCs in the in-vitro monolayer culture (P lt; 0.05), but it could significantly improve the protein expressions of collagen type II and Aggrecan in dedifferentiated NPCs, showing significantly difference between groups E and A (P lt; 0.05). The protein expressions of SIRT1, collagen type II, and Aggrecan in group B were significantly improved when compared with that in group A (P lt; 0.05). Real-time fluorescence quantitative PCR and Western blot showed that the expressions of SIRT1 mRNA and proteins in group C were significantly inhibited after transfected with SIRT1-siRNA when compared with those in groups B and D (P lt; 0.05), and the protein expressions of collagen type II and Aggrecan in group C were significantly lower than those in groups B and D (P lt; 0.05). Conclusion Continuous in-vitro monolayer culture could efficiently cultivate numerous seeding NPCs, but it is liable to dedifferentiate. In 3-D alginate microsphere culture, RES could restore the phenotype of dedifferentiated NPCs and synthesize more extracellular matrix, which is related to the regulation of SIRT1.
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.
Objective To evaluate the effectiveness of combining three-dimensional printing (3DP) models with three-dimensional visualization (3DV) technology in the teaching of thoracoscopic sublobar resection. Methods From March 2024 to June 2025, 150 interns were randomly assigned by envelope method to the 3DV, 3DP, and combined (3DV+3DP) groups. Three theoretical tests and score changes were used to assess short- and long-term teaching outcomes, and a questionnaire survey was conducted to analyze learning experience. Results After teaching, scores improved significantly in all groups (P<0.001), with the greatest increase in the combined group (47.18±5.81), which was higher than the 3DV and 3DP groups (P<0.001 and P=0.002, respectively). At 1 month, scores declined in all groups (P=0.028), but the combined group showed the smallest decrease (−6.94 ± 6.05). The combined group also showed the most pronounced advantage in spatial cognition (38.0%). Conclusion Innovative 3DP+3DV instructional model improves sublobar lung resection teaching and shows better long-term retention and spatial cognition.
Objective To investigate the cl inical results of the flap pedicled with collateral branch of descendingrarus of lateral circumflex femoral artery with digital three-dimensional reconstruction technique for lower l imb soft tissue defects. Methods Between March 2009 and January 2010, 7 patients with lower l imb soft tissue defects were treated with free flap pedicled with collateral branch of descending rarus of lateral circumflex femoral artery. There were 6 males and 1 female with an age range from 6 to 51 years. They were injured by traffic accident (4 cases), or by object hit from height (3 cases). The locations were foot in 2 cases, ankle in 2 cases, and anterior tibia in 3 cases. The disease duration was 8 hours to 40 days (mean, 20 days). All the cases compl icated by exposure of tendons or bones. The areas of soft tissue defect ranged from 12 cm × 7 cm to 20 cm × 14 cm. Free flaps were transplanted at 4 to 16 days after symptomatic treatment. Before operation, all the flaps were designed with digital three-dimensional reconstruction technique. The size of flaps ranged from 15 cm × 9 cm to 22 cm × 16 cm The donor sites were closed directly in all cases. Results All the flaps survived. The wounds and incisions at donor sites healed by first intention. All the patients were followed up 6 to 12 months. The texture, appearance, and function of the flaps were satisfactory, and no compl ication occurred. All the flaps had protective sensation, which could meet the requirement of the daily l ife. The function of ankle was satisfactory with normal walk; the extension was 19-22° and the flexion was 30-36°. No obvious scar formed at donor sites. Conclusion The flap pedicled with collateral branch of descending rarus of lateral circumflex femoral artery has rel iable blood supply, easy operation, l ittle influence on the donor site, and high success rate with digital three-dimensional reconstruction technique. It is an excellent option for repairing lower l imb soft tissue defects.