Objective: To summarize the research progress of bio-derived materials used for bladder regeneration and repair.
Methods: The recent domestic and foreign sutudies on bio-derived materials used for bladder regeneration and repair, including classification, morphology optimization process, tissue regeneration strategies, and relevant clinical trials, were summarized and analyzed.
Results: Numerous types of bio-derived materials are employed in bladder regeneration and repair, characterized by their low immunogenicity and high inducible activity. Surface modification, gelation, and other morphology optimization process have significantly broadened the application scope of bio-derived materials. These advancements have effectively addressed complications, such as perforation and urolith formation, that may arise during bladder regeneration and repair. The strategy of tissue regeneration utilizing bio-derived materials, targeting the regeneration of bladder epithelium, smooth muscle, blood vessels, and nerves, offers a novel approach to achieving functional regeneration of bladder. Bio-derived materials show great promise for use in bladder regeneration and repair, yet the results from clinical trials with these materials have been less than satisfactory.
Conclusion: Bio-derived materials are widely used in bladder regeneration and repair due to the good biocompatibility, low immunogenicity, and degradable properties, yet face a series of problems, and there are no commercialized bladder tissue engineering grafts used in clinical treatment.
Objective: To evaluate the clinical diagnostic value of knee MRI at 90° flexed position for Ramp lesions of medial meniscus.
Methods: A total of 228 patients with knee pain as the main complaint who were admitted between September 2021 and September 2023 was selected as the research subjects, of which 51 patients met the selection criteria and were enrolled in the study. There were 31 males and 20 females with an average age of 38.6 years (range, 15-67 years). Body mass index was 17.2-28.7 kg/m 2 (mean, 23.9 kg/m 2). There were 25 cases of left knee and 36 cases of right knee. The time from injury to admission was 0.1-14.3 weeks (mean, 2.1 weeks). Preoperative knee MRI at fully extended position (knee extension position) and 90° flexed position (knee flexion position) were performed to determine the presence of irregular signs at the posterior edge of the medial meniscus, and PHMM fluid high signal [i.e. complete fluid filling between the posterior horn of the medial meniscus (PHMM) and the capsule margin]. Findings obtained under arthroscopy served as the "gold standard" to analyze the sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of MRI at knee extension and flexion positions for the two specific signs of Ramp lesion.
Results: Twenty-one patients (41.2%) were diagnosed with Ramp lesions by using arthroscopy, including 1 case of Thaunat type Ⅰ, 2 cases of type Ⅱ, 6 cases of type Ⅲ, 7 cases of type Ⅳ, and 5 cases of type Ⅴ. The positive rates of irregular signs at the posterior edge of the medial meniscus on MRI at knee extension and flexion positions were significantly different from the diagnosis of Ramp injury under arthroscopy ( P<0.05). The sensitivity, specificity, accuracy, PPV, and NPV of MRI in the diagnosis of irregular signs were 76.1%, 60.0%, 66.7%, 57.1%, and 78.3% respectively at knee extension position, and 85.7%, 73.3%, 78.4%, 69.2%, and 88.0% respectively at knee flexion position. The positive rates of PHMM fluid high signal on MRI at knee extension and flexion positions were significantly different from the diagnosis of Ramp injury under arthroscopy ( P<0.05). The sensitivity, specificity, accuracy, PPV, and NPV of MRI in diagnosing PHMM fluid high signal were 38.1%, 100%, 74.5%, 100%, and 69.8% respectively at knee extension position, and 85.7%, 100%, 94.1%, 100%, and 90.9% respectively at knee flexion position.
Conclusion: Knee MRI at 90° flexed position improves the diagnostic performance of the detection of medial meniscal Ramp lesions compared with MRI at fully extended position.
Objective: To investigate the incidence of perioperative deep venous thrombosis (DVT) of lower extremities and its risk factors in elderly patients with femoral neck fracture.
Methods: The clinical data of 4 109 elderly patients with femoral neck fracture admitted between August 2012 and November 2020 and met the selection criteria were retrospectively analyzed. Among them, there were 1 137 males and 2 972 females; their ages ranged from 65 to 101 years, with an average of 77.0 years. The time from fracture to admission ranged from 1 to 360 hours, with an average of 35.2 hours. There were 1 858 cases of hemiarthroplasty, 1 617 cases of total hip arthroplasty, and 634 cases of internal fixation surgery. The preoperative age-adjusted Charlson comorbidity index (aCCI) was 4 (3, 5). Perioperative DVT occurred in 857 cases (20.9%). Univariate analysis was performed on age, gender, body mass index, fracture side, time from fracture to admission, operation type, anesthesia type, blood transfusion, blood pressure after admission, and preoperative aCCI in patients with and without perioperative DVT, and logistic regression analysis was used to screen the risk factors of perioperative DVT in elderly patients with femoral neck fracture.
Results: Univariate analysis showed that there were significant differences in age, gender, time from fracture to admission, operation type, and preoperative aCCI between the two groups ( P<0.05). Further logistic regression analysis showed that age>75 years, female patients, time from fracture to admission>24 hours, and preoperative aCCI>5 were risk factors for perioperative DVT ( P<0.05).
Conclusion: Elderly patients with femoral neck fracture have a higher incidence of perioperative DVT. The advanced aged and female patients, patients with longer fracture time and more comorbidities need to pay special attention to the prevention of perioperative DVT to minimize the occurrence of DVT during femoral neck fractures.
Objective: To review research progress on the design, manufacturing, and clinical application of three-dimensional (3D) printed customized prosthesis in acetabular reconstruction of hip revision surgery.
Methods: The related research literature on 3D printed customized prosthesis and its application in acetabular reconstruction of hip revision surgery was searched by key words of "3D printed customized prosthesis", "revision hip arthroplasty", "acetabular bone defect", and "acetabular reconstruction" between January 2013 and May 2024 in Chinese and English databases, such as CNKI, Wanfang database, PubMed, etc. A total of 34 271 articles were included. After reading the literature titles, abstracts, or full texts, the literature of unrelated, repetitive, low-quality, and low evidence level was screened out, and a total of 48 articles were finally included for analysis and summary.
Results: The bone growth and mechanical properties of 3D printed customized prosthesis materials are better than those of non-3D printed customized prosthesis, which further solves the problem of elastic modulus mismatch between the implant and natural bone caused by "stress shielding"; the porous structure and antibacterial coating on the surface of 3D printed customized prosthesis have good anti-bacterial effect. 3D printed customized prosthesis can perfectly match the patient's individual acetabular anatomical characteristics and defect type, thus improving the accuracy of acetabular reconstruction and reducing the surgical time and trauma.
Conclusion: 3D printed customized prosthesis can be used for precise and efficient individualized acetabular reconstruction in hip revision surgery with good early- and mid-term effectiveness. More optimized production technics and procedures need to be developed to improve the efficiency of clinical application and long-term effectiveness.
Objective: To investigate the anti-adhesive effect and underlying mechanism of dynamic and static stress stimulation on the early healing process of rat Achilles tendon injury.
Methods: Achilles tendon tissues of 15 male Sprague Dawley (SD) rats aged 4-6 weeks were isolated and cultured by enzyme digestion method. Rat Achilles tendon cells were treated with tumor necrosis factor α to construct the Achilles tendon injury cell model, and dynamic stress stimulation (dynamic group) and static stress stimulation (static group) were applied respectively, while the control group was not treated. Live/dead cell double staining was used to detect cell activity, ELISA assay was used to detect the expression of α smooth muscle actin (α-SMA), and real-time fluorescence quantitative PCR was used to detect the mRNA expression of collagen type Ⅰ (COL1A1), collagen type Ⅲ (COL3A1), and Scleraxis (SCX). Thirty male SD rats aged 4-6 weeks underwent Achilles tendon suture and were randomly divided into dynamic group (treated by dynamic stress stimulation), static group (treated by static stress stimulation), and control group (untreated), with 10 rats in each group. HE staining and scoring were performed to evaluate the healing of Achilles tendon at 8 days after operation. COL1A1 and COL3A1 protein expressions were detected by immunohistochemical staining, α-SMA and SCX protein expressions were detected by Western blot, and maximum tendon breaking force and tendon stiffness were detected by biomechanical stretching test.
Results: In vitro cell experiment, when compared to the static group, the number of living cells in the dynamic group was higher, the expression of α-SMA protein was decreased, the relative expression of COL3A1 mRNA was decreased, and the relative expression of SCX mRNA was increased, and the differences were all significant ( P<0.05). In the in vivo animal experiment, when compared to the static group, the tendon healing in the dynamic group was better, the HE staining score was lower, the expression of COL1A1 protein was increased, the expression of COL3A1 protein was decreased, the relative expression of SCX protein was increased, the relative expression of α-SMA protein was decreased, and the tendon stiffness was increased, the differences were all significant ( P<0.05).
Conclusion: Compared with static stress stimulation, the dynamic stress stimulation improves the fibrosis of the scar tissue of the rat Achilles tendon, promote the recovery of the biomechanical property of the Achilles tendon, and has obvious anti-adhesion effect.
Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disease caused by mutations in the NF1 gene. The disease is characterized by neurofibromatosis, which simultaneously affects multiple systems such as nerves, skin, and bone, and has complex clinical manifestations. Since the National Institutes of Health (NIH) established diagnostic criteria in 1988, the diagnosis and treatment of NF1 have progressed significantly. However, due to the complexity of the disease and the lack of effective treatments, the diagnosis and treatment of NF1 still face many challenges. Strengthening multidisciplinary collaboration, improving and popularizing disease diagnosis and treatment strategies, and developing more effective drugs and treatment methods are the keys to further improve the treatment level of NF1 diseases.