In order to find an ideal biological material to prevent peridural adhesion following laminectomy, 30 rabbits were used as animal model, in each of which 2 defects with a size of 1 cm x 0.5 cm were made following laminectomy of L3, L5 spine. One of the defects was covered extradurally with chitosan, gelatin foam or PLA membrane respectively, while the other defect was exposed as control. All of these animals were sacrificed on the 2nd, 4th, 6th, 8th and 10th week after operation, and the extradural fibrosis and adhesion of every animal were evaluated by gross observation and histological examinations. It was revealed that in the chitosan and PLA membrane groups, the extradural tissue was smooth without thickening and there was no fibrous proliferation or adhesion in the epidural cavity, and that in the chitosan group, the growth of fibroblast was restrained but the growth of the epithelial cells was promoted significantly, thus, wound healing was rapid. In the control group and gelatin foam group, obvious extradural fibrosis and adhesion were observed and the extradural space had almost disappeared. Therefore, it was concluded that the biodegradable PLA membrane and chitosan were both an ideal material in the prevention of postoperative epidural adhesion.
UK Biobank (UKB) is a forward-looking epidemiological project with over 500, 000 people aged 40 to 69, whose image extension project plans to re-invite 100, 000 participants from UKB to perform multimodal brain magnetic resonance imaging. Large-scale multimodal neuroimaging combined with large amounts of phenotypic and genetic data provides great resources to conduct brain health-related research. This article provides an in-depth overview of UKB in the field of neuroimaging. Firstly, neuroimage collection and imaging-derived phenotypes are summarized. Secondly, typical studies of UKB in neuroimaging areas are introduced, which include cardiovascular risk factors, regulatory factors, brain age prediction, normality, successful and morbid brain aging, environmental and genetic factors, cognitive ability and gender. Lastly, the open challenges and future directions of UKB are discussed. This article has the potential to open up a new research field for the prevention and treatment of neurological diseases.
The stiffness of an ideal fracture internal fixation implant should have a time-varying performance, so that the fracture can generate reasonable mechanical stimulation at different healing stages, and biodegradable materials meet this performance. A topology optimization design method for composite structures of fracture internal fixation implants with time-varying stiffness is proposed, considering the time-dependent degradation process of materials. Using relative density and degradation residual rate to describe the distribution and degradation state of two materials with different degradation rates and elastic modulus, a coupled mathematical model of degradation simulation mechanical analysis was established. Biomaterial composite structures were designed based on variable density method to exhibit time-varying stiffness characteristics. Taking the bone plate used for the treatment of tibial fractures as an example, a composite structure bone plate with time-varying stiffness characteristics was designed using the proposed method. The optimization results showed that material 1 with high stiffness formed a columnar support structure, while material 2 with low stiffness was distributed at the degradation boundary and inside. Using a bone remodeling simulation model, the optimized bone plates were evaluated. After 11 months of remodeling, the average elastic modulus of callus using degradable time-varying stiffness plates, titanium alloy plates, and stainless steel plates were 8 634 MPa, 8 521 MPa, and 8 412 MPa, respectively, indicating that the use of degradable time-varying stiffness plates would result in better remodeling effects on the callus.
Objective To review the development of endoscopic techniques in breast surgery, focusing on their use in benign breast lump resection and breast-conserving surgery for cancer, and also summarize the development and application of these techniques in China, highlighting promotion and homogenization challenges and future directions. Methods A systematic review of relevant literature was conducted to trace the historical evolution, clinical applications, and related research of endoscopic techniques in breast surgery, emphasizing their advantages and disadvantages of endoscopic benign breast lump resection and breast-conserving surgery for cancer. Results Endoscopic benign breast lump resection and breast-conserving surgery for cancer have improved patients’ postoperative psychological health and quality of life, particularly in scar-free surgery. However, challenges such as limited intraoperative visibility and prolonged surgery time lead to controversy in clinical practice. Conclusion Despite significant advancements, endoscopic techniques in breast surgery also face challenges. Future efforts should focus on technological improvements and clinical research to address these issues, promoting widespread application and standardization. The key to future development lies in the promotion and homogenization of these technologies.
Objective To evaluate the effectiveness of microplate fixation in open-door cervical expansive laminoplasty (ELP) by comparing with anchor fixation. Methods Between January 2005 and October 2008, 35 patients with multi-segment cervical spondylotic myelopathy were treated. Of them, 15 patients underwent ELP by microplate fixation (microplate group) and 20 patients underwent ELP by anchor fixation (anchor group). In microplate group, there were 10 malesand 5 females with the age of (51.2 ± 11.5) years; the disease duration ranged from 6 to 60 months (mean, 14 months); and the preoperative Japanese Orthopoaedic Association (JOA) score was 7.7 ± 2.5. In anchor group, there were 13 males and 7 females with the age of (50.7 ± 10.8) years; the disease duration ranged from 3 to 58 months (mean, 17 months); and the preoperative JOA score was 7.8 ± 2.9. There was no significant difference in the general data, such as gender, age, and JOA score between 2 groups (P gt; 0.05). Results All incisions healed by first intention. Thirty-five cases were followed up 24-68 months (mean, 32 months). The operation time was (113 ± 24) minutes in anchor group and (111 ± 27) minutes in microplate group, showing no significant difference (t=0.231 3, P=0.818 5). The rate of spinal canal expansion in microplate group (60% ± 24%) was significantly higher than that in anchor group (40% ± 18%) (t=2.820, P=0.008). The JOA scores of 2 groups at 3 months and 24 months after operation were significantly higher than the preoperative scores (P lt; 0.01). There was no significant difference in JOA score between 2 groups at 3 months after operation (t=1.620 5, P=0.114 6), but the JOA score of microplate group was significantly higher than that of anchor group at 24 months after operation (t=3.454 3, P=0.001 5). X-ray film, MRI, and CT scan at 3-6 months after operation displayed that door spindle reached bony fusion. There was no occurrence of ‘‘re-close of door’’ in 2 groups. The rate of compl ication in microplate group (13.3%, 2/15) was significantly lower than that in anchor group (25.0%, 5/20) (χ2=7.160 0, P=0.008 6). Conclusion ELP by microplate fixation can achieve the stabil ity quickly after operation, which can help patients to do functional exercises early, and has satisfactory effectiveness and less complications.
Objective To investigate the effect of methylprednisolone sodium succinate (MP) and mouse nerve growth factor (mNGF) for injection in treating acute spinal cord injury (ASCI) and cauda equina injury. Methods Between December 2004 and December 2007, 43 patients with ASCI and cauda equina injury were treated, including 33 males and 10 females with an average age of 43 years (range, 32-66 years). Injured vertebral columns were C2 in 1 case, C4 in 5 cases, C5 in 7cases, C6 in 3 cases, T8 in 1 case, T10 in 1 case, T11 in 2 cases, T12 in 3 cases, L1 in 9 cases, L2 in 5 cases, L3 in 3 cases, L4 in 1 case, and L5 in 2 cases. All the patients had sensory disturbance and motor dysfunction at admission. The Frankel scale was used for assessment of nerve function, 5 cases were rated as Grade A, 12 as Grade B, 22 as Grade C, and 4 as Grade D before operation. In 43 patients, 23 cases were treated with MP and mNGF (group A), 20 cases with MP only (group B). There was no significant difference in general data between 2 groups (P gt; 0.05). All the patients were admitted, received drug treatment within 8 hours of injury, and were given spinal canal decompression, bone transplantation, and internal fixation within 48 hours. The neurological function score systems of American Spinal Injury Association (ASIA) were used for neurological scores before treament, at 1 week and 2 years after treatment. The scores of the activity of daily l iving (ADL) were evaluated and compared. Results All the patients achieved heal ing of incision by first intention. Forty-three cases were followed up 24-61 months with an average of 30 months. Bone graft fusion was achieved after 6-17 months, 11 months on average with stable fixation. No death and compl ications of osteonecrosis and central obesity occurred. There was no significant difference in neurological function scores and ADL scores between 2 groups before treatment (P gt; 0.05); however, the neurological function scores and ADL scores at 1 week and 2 years after treatment were higher than those before treatment (P lt; 0.01) in 2 groups. Group A had higher neurological function scores and ADL scores than group B (P lt; 0.01). At 1 week and 2 years after treatment, the improvement rates of neurological function of group A (47.8%, 11/23 and 91.3%, 21/23) were significantly higher (P lt; 0.01) than those of group B (30.0%, 6/20 and 70.0%, 14/20). Conclusion MP and mNGF play an important role in improving the neurological function in patients with ASCI and cauda equina injury.