Unicompartmental knee arthroplasty combined with posterior cruciate ligament reconstruction: a case report.

BACKGROUND: In this study, we present the unique case of a patient with knee osteoarthritis (OA) of the medial compartment and posterior cruciate ligament (PCL) deficiency who underwent simultaneous medial unicompartmental knee arthroplasty (UKA) and PCL reconstruction. CASE PRESENTATION: A 49-year-old male patient presented with a 1-year history of pain and instability in the left knee. The patient had previously experienced a trauma-related injury to the PCL of the left knee that was left untreated. Imaging and physical examination confirmed the presence of left medial knee OA along with PCL rupture. To address these issues, the patient underwent UKA combined with PCL reconstruction. The patient's Lysholm score was 47 before surgery and 81 three months after surgery, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score was 29 before surgery and 18 three months after surgery, and the International Knee Documentation Committee (IKDC) subjective score was 56.3 before surgery and 74.7 three months after surgery. Six months after surgery, the patient's gait returned to normal, and he was able to jog. CONCLUSION: This case report presents the first instance of UKA combined with PCL reconstruction and introduces a novel treatment approach for patients suffering from medial knee OA and ligament injury.

Effect of Perineural or Intravenous Betamethasone on Femoral Nerve Block Outcomes in Knee Arthroplasty: A Randomized, Controlled Study.

OBJECTIVES: Despite the use of multimodal analgesia, patients undergoing knee arthroplasty still encounter residual moderate pain. The addition of betamethasone to local anesthetic has been shown to improve postoperative pain. However, it remains uncertain whether the positive effects of perineural or intravenous administration of betamethasone on analgesia outcomes lead to better early mobility and postoperative recovery. METHODS: Between June 2022 and February 2023, a total of 159 patients who were undergoing knee arthroplasty were included in this study. These patients were allocated randomly into three groups: (i) the NS group, received ropivacaine 0.375% and intravenous 3mL 0.9% normal saline; (ii) the PNB group, received ropivacaine 0.375% plus perineural betamethasone (12mg) 3mL and intravenous 3mL 0.9% normal saline; and (iii) the IVB group, received ropivacaine 0.375% and intravenous betamethasone (12mg) 3mL. RESULTS: Both perineural and intravenous administration of betamethasone led to improved median (IQR) numeric rating scale (NRS) scores on the 6-meter walk test, with a score of 1.0 (1.0-2.0) for both groups, compared with 2.0 (1.0-2.0) for the NS group (p = 0.003). Compared to the NS group, both the PNB and IVB groups showed significant reductions in NRS scores at 24 and 36 h after surgery, along with a significant increase in ROM at 24, 36, and 48 h post-operation. Additionally, it exhibited lower levels of cytokine IL-1ß and TNF-α in fluid samples, as well as lower level of HS-CRP in blood samples in the PNB and IVB groups compared to the NS group. CONCLUSION: The administration of perineural and intravenous betamethasone demonstrated an enhanced analgesic effect following knee arthroplasty. Furthermore, it was associated with reduced levels of IL-1ß, TNF-α, and HS-CRP, as well as enhanced knee ROM, which is conducive to early ambulation and postoperative rehabilitation after knee arthroplasty.

Large-scale pancreatic cancer detection via non-contrast CT and deep learning.

Pancreatic ductal adenocarcinoma (PDAC), the most deadly solid malignancy, is typically detected late and at an inoperable stage. Early or incidental detection is associated with prolonged survival, but screening asymptomatic individuals for PDAC using a single test remains unfeasible due to the low prevalence and potential harms of false positives. Non-contrast computed tomography (CT), routinely performed for clinical indications, offers the potential for large-scale screening, however, identification of PDAC using non-contrast CT has long been considered impossible. Here, we develop a deep learning approach, pancreatic cancer detection with artificial intelligence (PANDA), that can detect and classify pancreatic lesions with high accuracy via non-contrast CT. PANDA is trained on a dataset of 3,208 patients from a single center. PANDA achieves an area under the receiver operating characteristic curve (AUC) of 0.986-0.996 for lesion detection in a multicenter validation involving 6,239 patients across 10 centers, outperforms the mean radiologist performance by 34.1% in sensitivity and 6.3% in specificity for PDAC identification, and achieves a sensitivity of 92.9% and specificity of 99.9% for lesion detection in a real-world multi-scenario validation consisting of 20,530 consecutive patients. Notably, PANDA utilized with non-contrast CT shows non-inferiority to radiology reports (using contrast-enhanced CT) in the differentiation of common pancreatic lesion subtypes. PANDA could potentially serve as a new tool for large-scale pancreatic cancer screening.

Non-enhanced magnetic resonance imaging-based radiomics model for the differentiation of pancreatic adenosquamous carcinoma from pancreatic ductal adenocarcinoma.

Purpose: To evaluate the diagnostic performance of radiomics model based on fully automatic segmentation of pancreatic tumors from non-enhanced magnetic resonance imaging (MRI) for differentiating pancreatic adenosquamous carcinoma (PASC) from pancreatic ductal adenocarcinoma (PDAC). Materials and methods: In this retrospective study, patients with surgically resected histopathologically confirmed PASC and PDAC who underwent MRI scans between January 2011 and December 2020 were included in the study. Multivariable logistic regression analysis was conducted to develop a clinical and radiomics model based on non-enhanced T1-weighted and T2-weighted images. The model performances were determined based on their discrimination and clinical utility. Kaplan-Meier and log-rank tests were used for survival analysis. Results: A total of 510 consecutive patients including 387 patients (age: 61 ± 9 years; range: 28-86 years; 250 males) with PDAC and 123 patients (age: 62 ± 10 years; range: 36-84 years; 78 males) with PASC were included in the study. All patients were split into training (n=382) and validation (n=128) sets according to time. The radiomics model showed good discrimination in the validation (AUC, 0.87) set and outperformed the MRI model (validation set AUC, 0.80) and the ring-enhancement (validation set AUC, 0.74). Conclusions: The radiomics model based on non-enhanced MRI outperformed the MRI model and ring-enhancement to differentiate PASC from PDAC; it can, thus, provide important information for decision-making towards precise management and treatment of PASC.

Deep Learning for Fully Automated Prediction of Overall Survival in Patients Undergoing Resection for Pancreatic Cancer: A Retrospective Multicenter Study.

OBJECTIVE: To develop an imaging-derived biomarker for prediction of overall survival (OS) of pancreatic cancer by analyzing preoperative multiphase contrast-enhanced computed topography (CECT) using deep learning. BACKGROUND: Exploiting prognostic biomarkers for guiding neoadjuvant and adjuvant treatment decisions may potentially improve outcomes in patients with resectable pancreatic cancer. METHODS: This multicenter, retrospective study included 1516 patients with resected pancreatic ductal adenocarcinoma (PDAC) from 5 centers located in China. The discovery cohort (n=763), which included preoperative multiphase CECT scans and OS data from 2 centers, was used to construct a fully automated imaging-derived prognostic biomarker-DeepCT-PDAC-by training scalable deep segmentation and prognostic models (via self-learning) to comprehensively model the tumor-anatomy spatial relations and their appearance dynamics in multiphase CECT for OS prediction. The marker was independently tested using internal (n=574) and external validation cohorts (n=179, 3 centers) to evaluate its performance, robustness, and clinical usefulness. RESULTS: Preoperatively, DeepCT-PDAC was the strongest predictor of OS in both internal and external validation cohorts [hazard ratio (HR) for high versus low risk 2.03, 95% confidence interval (CI): 1.50-2.75; HR: 2.47, CI: 1.35-4.53] in a multivariable analysis. Postoperatively, DeepCT-PDAC remained significant in both cohorts (HR: 2.49, CI: 1.89-3.28; HR: 2.15, CI: 1.14-4.05) after adjustment for potential confounders. For margin-negative patients, adjuvant chemoradiotherapy was associated with improved OS in the subgroup with DeepCT-PDAC low risk (HR: 0.35, CI: 0.19-0.64), but did not affect OS in the subgroup with high risk. CONCLUSIONS: Deep learning-based CT imaging-derived biomarker enabled the objective and unbiased OS prediction for patients with resectable PDAC. This marker is applicable across hospitals, imaging protocols, and treatments, and has the potential to tailor neoadjuvant and adjuvant treatments at the individual level.

Pravastatin Reduces Matrix Metalloproteinases Expression and Promotes Cholesterol Efflux in Osteoarthritis Chondrocytes.

Background: Chondrocyte metabolic disorder plays an important role in the development of osteoarthritis (OA). The use of statins in the treatment of OA has also been widely studied, but the mechanism is still confusing. The present study aims to investigate the effects of statin on osteoarthritis chondrocytes and its underlying mechanism. Major findings. An untargeted metabolomics study revealed that the treatment of statins significantly changed the metabolites of articular cartilage tissues collected from female osteoarthritis patients, and might be involved in the glycerophospholipid metabolism pathway. In vitro study showed that 5-50 µmol/L of pravastatin exerts no cytotoxicity on human chondrocytes. Besides, 50 µmol/L of pravastatin caused a significant decrease in the expression of matrix metalloproteinase (MMP)-1 and MPP-13, and intracellular cholesterol in interleukin-1ß (IL-1ß)-induced human chondrocytes. Furthermore, at both mRNA and protein levels, the expression of the proteins related to the cholesterol efflux pathway (liver X receptor and cholesterol efflux regulatory protein) were significantly up-regulated by 50 µmol/L of pravastatin in IL-1ß-induced human chondrocytes. Conclusion: Pravastatin can reduce the expression of MMPs in IL-1ß-induced human chondrocytes and protect the chondrocyte matrix. The mechanism may be related to promoting the expression of proteins related to the cholesterol efflux pathway and reducing the level of cellular cholesterol.

Stromal cell-derived factor-1 promotes osteoblastic differentiation of human bone marrow mesenchymal stem cells via the lncRNA-H19/miR-214-5p/BMP2 axis.

BACKGROUND: Stromal cell-derived factor-1 (SDF-1) plays an important role in the osteoblastic differentiation of human bone marrow mesenchymal stem cells (hBMMSCs), but the specific mechanism remains unclear. Our study aimed to clarify the role of the lncRNA-H19/miR-214-5p/BMP2 axis in the osteoblastic differentiation of hBMMSCs induced by SDF-1. METHODS: We used reverse-transcriptase polymerase chain reaction, western blotting, alkaline phosphatase activity test, and Alizarin red staining to evaluate the osteoblastic differentiation of primary hBMMSCs and the luciferase reporter assay to determine if lncRNA-H19 binds with miR-214-5p. RESULTS: Our results indicated that SDF-1 (50 ng/mL) promotes the osteoblastic differentiation of hBMMSCs, significantly upregulates osteoblastogenic genes (OCN, OSX, RUNX2, and ALP), and increases Alizarin red staining, alkaline phosphatase activity, and lncRNA-H19 expression. Luciferase reporter assay verified that lncRNA-H19 binds with and represses miR-214-5p, thereby upregulating BMP2 expression. Use of miR-214-5p inhibitor or overexpression of lncRNA-H19 can promote the osteoblastic differentiation of hBMMSCs, but miR-214-5p or shH19 inhibits the osteoblastic differentiation of hBMMSCs. Treatment with an miR-214-5p inhibitor could rescue the inhibitory effect of shH19 on the osteoblastic differentiation of hBMMSCs. CONCLUSIONS: Taken together, SDF-1 promotes the osteoblastic differentiation of hBMMSCs through the lncRNA-H19/miR-214-5p/BMP2 axis. Increased osteoblastic differentiation by an miR-214-5p inhibitor reveals a new possible strategy for the treatment of bone defect and osteoporosis.

miR-142-5p protects against osteoarthritis through competing with lncRNA XIST.

BACKGROUND: The relevance between abnormal microRNA expression and osteoarthritis (OA) has been elaborated in recent studies. Hence, the present study aimed to assess the impact of miR-142-5p on chondrocyte growth and apoptosis. METHODS: To mimic OA-like chondrocyte damage, interleukin (IL)-1ß was used for chondrocyte treatment. The expression of miR-142-5p, SGTB, long non-coding RNA (lncRNA) X inactive specific transcript (XIST) and involved molecules such as Col2A1, Bcl-2, MMP13 and Bax was determined via a quantitative reverse transcriptase-polymerase chain reaction and western blot analyses. Functional roles of miR-142-5p, SGTB and XIST were monitored in 5-ethynyl-2'-deoxyuridine, CCK-8 and TUNEL experiments. Rescue analyses were conducted to consolidate the effect of the XIST/miR-142-5p/SGTB axis on chondrocytes in OA. RESULTS: miR-142-5p was down-regulated in IL-1ß-treated chondrocytes, whereas SGTB and XIST levels were increased. Overexpression of miR-142-5p stimulated proliferation and retarded apoptosis in IL-1ß-treated chondrocytes. Meanwhile, miR-142-5p elevation was correlated with an elevation of Col2A1 and Bcl-2, as well as a decline of MMP13 and Bax. A mechanistic study showed that miR-142-5p negatively regulated SGTB expression. Moreover, we found that lncRNA XIST could relieve the inhibition of miR-142-5p on SGTB expression. Augmentation of SGTB or suppression of miR-142-5p reversed the influence of XIST depletion on chondrocyte growth and apoptosis. CONCLUSIONS: The present study has explored the fundamental role of miR-142-5p in IL-1ß-treated chondrocytes, as well as the novel molecular mechanism constituted by miR-142-5p/SGTB/XIST in OA. Potentially, the results obtained may add new insight into OA pathogenesis.

Mesenchymal Stem Cells for Regenerative Medicine.

In recent decades, the biomedical applications of mesenchymal stem cells (MSCs) have attracted increasing attention. MSCs are easily extracted from the bone marrow, fat, and synovium, and differentiate into various cell lineages according to the requirements of specific biomedical applications. As MSCs do not express significant histocompatibility complexes and immune stimulating molecules, they are not detected by immune surveillance and do not lead to graft rejection after transplantation. These properties make them competent biomedical candidates, especially in tissue engineering. We present a brief overview of MSC extraction methods and subsequent potential for differentiation, and a comprehensive overview of their preclinical and clinical applications in regenerative medicine, and discuss future challenges.

Correcting pelvic obliquity in the lateral position to improve acetabular component orientation during total hip arthroplasty.

BACKGROUND: The acetabular component orientation during total hip arthroplasty (THA) impacts future hip function and early revision. Correcting pelvic obliquity may improve outcomes. OBJECTIVE: To correct pelvic obliquity in the lateral position by applying a gradienter and plumb during THA using fluoroscopy. METHODS: Fifty patients undergoing THA were randomized and divided into 2 groups. In controls, acetabular components were placed using traditional methods. In experimental patients, acetabular components were placed after correcting pelvic obliquity. We measured pelvic obliquity and recorded intra-operative and post-operative abduction angles, comparing abduction angle bias between post-operative measurements and intra-operation estimations. RESULTS: Before correction, the average pelvic obliquity was -1.647∘± 4.512∘ in experimental patients. The average abduction angle in experimental patients was 42.685∘± 3.355∘ postoperatively, differing by 1.962∘± 1.515∘ from intra-operative estimates, while in control patients, it was 44.534∘± 4.844∘ postoperatively, differing by 4.244∘± 3.042∘ from intra-operative estimates. The bias of the abduction angle was much greater in control than in experimental patients (P< 0.05). CONCLUSION: The pelvic obliquity in the lateral position affects surgeon judgment during THA. By correcting pelvic obliquity with a gradienter and plumb, the abduction angle bias can be reduced.

Kartogenin-Incorporated Thermogel Supports Stem Cells for Significant Cartilage Regeneration.

Recently, cartilage tissue engineering (CTE) attracts increasing attention in cartilage defect repair. In this work, kartogenin (KGN), an emerging chondroinductive nonprotein small molecule, was incorporated into a thermogel of poly(L-lactide-co-glycolide)-poly(ethylene glycol)-poly(L-lactide-co-glycolide) (PLGA-PEG-PLGA) to fabricate an appropriate microenvironment of bone marrow mesenchymal stem cells (BMSCs) for effective cartilage regeneration. More integrative and smoother repaired articular surface, more abundant characteristic glycosaminoglycans (GAGs) and collagen II (COL II), and less degeneration of normal cartilage were obtained in the KGN and BMSCs coloaded thermogel group in vivo. In conclusion, the KGN-loaded PLGA-PEG-PLGA thermogel can be utilized as an alternative support for BMSCs to regenerate damaged cartilage in vivo.

Cross-sectional Anatomy of Ilium for Guiding Acetabular Component Placement Using High Hip Center Technique in Asian Population.

BACKGROUND: Many clinical studies have been published involving the use of a high hip center (HHC), achieved good follow-up. However, there is a little anatomic guidance in the literature regarding the amount of bone stock available for initial implant coverage in this area of the ilium. The purpose of this study was to evaluate the thickness and width of the human ilium and related acetabular cup coverage for guiding acetabular component placement in HHC. METHODS: A total of 120 normal hips in 60 cases of adult patients from lower extremities computer tomographic angiography Digital Imaging and Communications in Medicine data were chosen for the study. After importing the data to the mimics software, we chose the cross sections every 5-mm increments from the rotational center of the hip to the cephalic of the ilium according the body sagittal axis, then we measured the thickness and width of the ilium for each cross section in axial plane, calculated the cup coverage at each chosen section. RESULTS: At the acetabular dome, the mean thickness and width of the ilium were 49.71 ± 4.88 mm and 38.92 ± 3.67 mm, respectively, whereas at 1 cm above the dome, decreased to 41.35 ± 5.13 and 31.13 ± 3.37 respectively, and 2 cm above the dome, decreased to 31.25 ± 4.04 and 26.65 ± 3.43, respectively. Acetabular cup averaged coverage for 40-, 50-, and 60-mm hemispheric shells, was 100%, 89%, and 44% at the acetabular dome, 100%, 43.7%, and 27.5% for 1 cm above the dome, and 37.5%, 21.9%, and 14.2% for 2 cm above the dome. CONCLUSIONS: HHC reconstructions within 1 cm above the acetabular dome will be an acceptable and smaller diameter prosthesis would be better.

Biomimetic biphasic scaffolds for osteochondral defect repair.

The osteochondral defects caused by vigorous trauma or physical disease are difficult to be managed. Tissue engineering provides a possible option to regenerate the damaged osteochondral tissues. For osteochondral reconstruction, one intact scaffold should be considered to support the regeneration of both cartilage and subchondral bone. Therefore, the biphasic scaffolds with the mimic structures of osteochondral tissues have been developed to close this chasm. A variety of biomimetic bilayer scaffolds fabricated from natural or synthetic polymers, or the ones loading with growth factors, cells, or both of them make great progresses in osteochondral defect repair. In this review, the preparation and in vitro and/or in vivo verification of bioinspired biphasic scaffolds are summarized and discussed, as well as the prospect is predicted.

Accuracy of the lesser trochanter for guiding lag screw insertion in hip fracture management.

The goal of this study was to evaluate the accuracy of the lesser trochanter for entry of lag screw placement in the fixation of hip fractures. Radiographs of the pelvis with both hips in 50 Chinese patients were analyzed to determine the accuracy of using the lesser trochanter as a reference landmark for inserting lag screws. The femoral neck was divided into 4 parts, and the second distal part was classified as the safe zone. Cobb angles of 125° and 130° were used as representative lag screw insertion angles, referencing the lateral cortex of the lesser trochanter for measurement, and insertion tracks were drawn on the neck of the femur. The accuracy of lag screw placement in the defined safe zone was evaluated. Accuracy of placement in the safe zone for entry points at the superior tip, apex, and inferior tip of the lesser trochanter were 78%, 39%, and 0%, respectively, for the 125° Cobb angle. Rates for the superior tip, apex, and inferior tip of the lesser trochanter were 31%, 74%, and 6%, respectively, for the 130° Cobb angle. The entry point at the level of the inferior tip of the lesser trochanter had incidence rates of 95% and 71% for cutout for 125° and 130° screws, respectively. The authors found that the superior tip of the lesser trochanter was a good reference point for 125° lag screw insertion and that the apex of the lesser trochanter was a good reference point for 130° lag screw insertion. Entry at the level of the inferior tip of the lesser trochanter has a very high rate of cutout and should be avoided.

Three-dimensional reconstruction method for measuring the knee valgus angle of the femur in northern Chinese adults.

The purpose of this study was to establish a method for measuring the knee valgus angle from the anatomical and mechanical axes on three-dimensional reconstruction imaging models, and to use this method for estimating an average knee valgus angle value for northern Chinese adults. Computed tomographic angiography data in DICOM format for 128 normal femurs from 64 adult subjects were chosen for analysis. After the femur images were subjected to three-dimensional reconstruction, the deepest point in the intercondylar notch (point A), the midpoint of the medullary cavity 20 cm above the knee-joint line (point B), and the landmark of the femoral head rotation center (point C) were identified on each three-dimensional model. The knee valgus angle was defined as the angle enclosed by the distal femoral anatomical axis (line AB) and the femoral mechanical axis (line AC). The average (mean±SD) of knee valgus angle for the 128 femurs was 6.20°±1.20° (range, 3.05° to 10.64°). Significant positive correlations were found between the knee valgus angles of the right and left sides and between the knee valgus angle and age. During total knee arthroplasty, choosing a valgus cut angle of approximately 6° may achieve a good result in reestablishing the natural mechanical alignment of the lower extremity for patients of northern Chinese ethnicity. Larger valgus cut angles should be chosen for older patients.

Improved method for planning intramedullary guiding rod entry point in total knee arthroplasty.

BACKGROUND: To study the accuracy of using the deepest point of the intercondylar notch (DPIN) as a reference point for femoral intramedullary (IM) guiding rod entrance in total knee arthroplasty (TKA) with 3-D reconstruction in Chinese subjects. METHODS: A total of 50 normal femurs in 25 Chinese subjects (mean age 25.6 ± 2.9 years; range 18-29 years) were chosen from the lower extremities computed tomography digital imaging and communications in medicine (DICOM) database for this study. The DICOM data were imported into Mimics 10.0 software. A cylinder (radius = 4 mm; length = 20 cm) was used to simulate ideal insertion of a IM guiding rod into the femoral canal. DPIN was taken as a reference point for calculating the relative position of the rod's entry point. RESULTS: The mean rod entry point position in the coronal plane was 2.94 ± 1.12 mm (range 0.79-4.91 mm) medial and 6.01 ± 2.09 mm (range 2.49-9.51 mm) anterior to the DPIN, with no significant difference between sides. All potential angle errors were below 2°. CONCLUSION: The results of this study show that the DPIN can serve as a reference for surgeons using an IM guide system in TKA.