Physical and chemical niche of human growth plate for polarized bone development.

Growth plate (GP), a critical cartilaginous structure in amniotes, underpins longitudinal bone growth, yet the intricate mechanisms behind its polarized mineralization during evolution remain unclear. Herein, employing high-resolution analytical techniques, we reveal that the GP-epiphysis interface displays a sharp transition in tissue modulus, acting as a protective shell for the underlying GP, whereas the GP-metaphysis interface exhibits a gradual modulus increase, enabling efficient load redistribution to the metaphysis. This mechanical microenvironment contributes to unique microstructural and compositional transformations from GP to epiphysis and metaphysis.

Biomechanical analysis of posterior, transforaminal, extreme, oblique, and anterior lumbar interbody fusion surgical models: a finite element study.

Many lumbar interbody fusion methods have been proposed, but there is a relative scarcity of fundamental biomechanical research on these varied surgical procedures. In this study, a finite element model of an L4-L5 functional spinal unit was created and five interbody fusion methods were evaluated, including posterior lumbar interbody fusion (PLIF), transforaminal lumbar interbody fusion (TLIF), extreme lateral interbody fusion (XLIF), oblique lateral interbody fusion (OLIF) and anterior lumbar interbody fusion (ALIF). Static and harmonic vibration surgery analysis models were developed based on it, investigating the biomechanical properties, as well as the variation of strain energy.

Development and validation of a nomogram prediction model for perioperative deep vein thrombosis risk in arthroplasty: a retrospective study.

Background: Perioperative monitoring thrombosis has become more crucial due to the rising demand for arthroplasty and shorter hospital stays. We aimed to comprehensively explore immune-inflammatory and hypercoagulable states during perioperative periods patients undergoing arthroplasty to identify the risk factors for early postoperative deep vein thrombosis (DVT) and construct a nomogram prediction model for postoperative DVT.

Methods: Electronic medical records of 841 patients who underwent primary arthroplasty at a single institution were retrospectively reviewed.

High-speed centrifugation reduces immune rejection by removing bone marrow elements from fresh osteochondral allografts.

Background: Fresh osteochondral allografts (OCAs) contain numerous immunogenic components in the subchondral bone (SB). Whether high-speed centrifugation (HSC) reduces immune rejection by removing bone marrow elements (BMEs), compared to methods without HSC, remains unknown. This study aimed to validate the efficacy and safety of HSC in reducing immune rejection by removing allogeneic BMEs.

A tough soft-hard interface in the human knee joint driven by multiscale toughening mechanisms.

Joining heterogeneous materials in engineered structures remains a significant challenge due to stress concentration at interfaces, which often leads to unexpected failures. Investigating the complex, multiscale-graded structures found in animal tissue provides valuable insights that can help address this challenge. The human meniscus root-bone interface is an exemplary model, renowned for its exceptional fatigue resistance, toughness, and interfacial adhesion properties throughout its lifespan.

Nanostructure-Mediated Photothermal Effect for Reinforcing Physical Killing Activity of Nanorod Arrays.

The physical killing of bacteria based on surface topography has attracted much attention due to the sustainable and safe prevention of biofilm formation. However, the antibacterial efficiency of biomedical implants derived solely from nanostructures or microstructures is insufficient to combat bacteria against common infections, such as methicillin-resistant Staphylococcus aureus with thick cell walls. Herein, photothermal therapy is carried out in the presence of nanorod arrays to mitigate infection of biomedical implants.

Integrated proteomics and metabolomics analysis of sclerosis-related proteins and femoral head necrosis following internal fixation of femoral neck fractures.

Femoral head necrosis (FHN) is a serious complication after femoral neck fractures (FNF), often linked to sclerosis around screw paths. Our study aimed to uncover the proteomic and metabolomic underpinnings of FHN and sclerosis using integrated proteomics and metabolomics analyses. We identified differentially expressed proteins (DEPs) and metabolites (DEMs) among three groups: patients with FNF (Group A), sclerosis (Group B), and FHN (Group C).

Biomechanical properties of articular cartilage in different regions and sites of the knee joint: acquisition of osteochondral allografts.

Osteochondral allograft (OCA) transplantation involves grafting of natural hyaline cartilage and supporting subchondral bone into the cartilage defect area to restore its biomechanical and tissue structure. However, differences in biomechanical properties and donor-host matching may impair the integration of articular cartilage (AC). This study analyzed the biomechanical properties of the AC in different regions of different sites of the knee joint and provided a novel approach to OCA transplantation.

High-Speed Centrifugation Efficiently Removes Immunogenic Elements in Osteochondral Allografts.

Objectives: The current clinical pulse lavage technique for flushing fresh osteochondral allografts (OCAs) to remove immunogenic elements from the subchondral bone is ineffective. This study aimed to identify the optimal method for removing immunogenic elements from OCAs.

Methods: We examined five methods for the physical removal of immunogenic elements from OCAs from the femoral condyle of porcine knees.

Near-infrared Ⅱ light-assisted Cu-containing porous TiO coating for combating implant-associated infection.

Treatment implant-associated infections remains a severe challenge in the clinical practice. This work focuses on the fabrication of Cu-containing porous TiO coatings on titanium (Ti) by a combination of magnetron sputtering and dealloying techniques. Additionally, photothermal therapy is employed to enhance the effect of Cu ions in preventing bacterial infection.

Treatment of Articular Cartilage Defects: A Descriptive Analysis of Clinical Characteristics and Global Trends Reported from 2001 to 2020.

Purpose: To evaluate the clinical characteristics and global trends in the surgical treatment of articular cartilage defects.

Methods: Studies in English published between January 1, 2001 and December 31, 2020 were retrieved from MEDLINE, WOS, INSPEC, SCIELO, KJD, and RSCI on the "Web of Science." Patient data were extracted, including age, sex, defect location and laterality, duration of follow-up and symptoms, and body mass index (BMI).

Characteristics and Clinical Outcomes After Osteochondral Allograft Transplantation for Treating Articular Cartilage Defects: Systematic Review and Single-Arm Meta-analysis of Studies From 2001 to 2020.

Background: Osteochondral allograft transplantation (OCA) treats symptomatic focal cartilage defects with satisfactory clinical results.

Purpose: To comprehensively analyze the characteristics and clinical outcomes of OCA for treating articular cartilage defects.

Study Design: Systematic review; Level of evidence, 4.

Prevention of sclerosis around cannulated screw after treatment of femoral neck fractures with bioceramic nails: a finite element analysis.

Purpose: Conventional cannulated screws (CS) are the main treatment method for femoral neck fractures (FNF). However, the rate of femoral head necrosis remains high after FNF treatment. The study aimed to compare the biomechanical features of different internal fixation materials for the treatment of Pauwel type III FNF to explore new strategies for clinical management.

Titanium alloy cannulated screws and biodegrade ceramic nails for treatment of femoral neck fractures: A finite element analysis.

Background: Our previous studies have demonstrated the mechanical effect of sclerosis around screw paths on the healing of femoral neck fractures (FNF) after internal fixation. Furthermore, we discussed the possibility of using bioceramic nails (BNs) to prevent sclerosis. However, all these studies were conducted under static conditions as the patient was standing on one leg, while the effect of the stress generated during movement is unknown.

The enhanced visible light driven photocatalytic activity of zinc porphyrin/g-CN nanosheet for efficient bacterial infected wound healing.

Graphitic carbon nitride (g-CN) has received much attention as a metal-free polymeric two-dimensional photocatalyst for antibiotic-free antibacterial application. However, the weak photocatalytic antibacterial activity of pure g-CN stimulated by visible light limits its applications. Herein, g-CN is modified with Zinc (II) meso-tetrakis (4-carboxyphenyl) porphyrin (ZnTCPP) by amidation reaction to enhance the utilization of visible light and reduce the recombination of electron-hole pairs.

Comparison of femoral mechanics before and after internal fixation removal and the effect of sclerosis on femoral stress: a finite element analysis.

Background: Femoral neck fractures are a common traumatic injury. The removal of the internal fixation remains controversial, especially in terms of mechanical stability. Moreover, collapsed necrosis of the femoral head continues to occur after fracture healing.

Stage-specific and location-specific cartilage calcification in osteoarthritis development.

Objectives: This study investigated the stage-specific and location-specific deposition and characteristics of minerals in human osteoarthritis (OA) cartilages via multiple nano-analytical technologies.

Methods: Normal and OA cartilages were serially sectioned for micro-CT, scanning electron microscopy with energy dispersive X-ray spectroscopy, micro-Raman spectroscopy, focused ion beam scanning electron microscopy, high-resolution electron energy loss spectrometry with transmission electron microscopy, nanoindentation and atomic force microscopy to analyse the structural, compositional and mechanical properties of cartilage in OA progression.

Results: We found that OA progressed by both top-down calcification at the joint surface and bottom-up calcification at the osteochondral interface.

α2-macroglobulin-rich serum as a master inhibitor of inflammatory factors attenuates cartilage degeneration in a mini pig model of osteoarthritis induced by "idealized" anterior cruciate ligament reconstruction.

Post-traumatic osteoarthritis is a special type of osteoarthritis and a common disease, with few effective treatments available. α2-Macroglobulin (α2M) is important to chondral protection in post-traumatic osteoarthritis. However, its injection into xenogeneic joint cavities involves safety hazards, limiting clinical applications.

Nanostructured Cu-doped TiO with photothermal effect for prevention of implant-associated infection.

Bacterial infection of titanium (Ti) dental implants is still a major clinical complication. In this study, a combination of copper (Cu) ions and photothermal therapy is used to combat implant-associated infection. Cu doped TiO (TiO-Cu) films were prepared on Ti by magnetron sputtering and subsequently annealing.

Micro-Computed Tomography Analysis of Femoral Head Necrosis After Long-Term Internal Fixation for Femoral Neck Fracture.

Objective: To analyze necrotic femoral head after long-term internal fixation for femoral neck fractures using micro-computed tomography (CT) for bone histomorphometry.

Methods: The experimental group included six patients (two men and four women; mean age 62.00 ± 9.

[Clinical effects of arthroscopy-assisted anterior cruciate ligament tibial eminence avulsion fracture compared with traditional open surgery:a Meta-analysis].

Objective: To systematically evaluate the clinical efficacy of arthroscopy and traditional incision in the treatment of tibial avulsion fracture of anterior cruciate ligament (ACL).

Methods: From July 2010 to July 2020, clinical comparative trial about arthroscopy and traditional incision in the treatment of ACL tibial avulsion fracture was conducted by using computer-based databases, including Embase, Pubmed, Central, Cinahl, PQDT, CNKI, Weipu, Wanfang, Cochrane Library, CBM. Literature screening and data extraction were carried out according to the inclusion and exclusion criteria, and the quality of the included literature was evaluated by improved Jadad score and Ottawa Newcastle scale (NOS).

Identification of an Ultrathin Osteochondral Interface Tissue with Specific Nanostructure at the Human Knee Joint.

Cartilage adheres to subchondral bone via a specific osteochondral interface tissue where forces are transferred from soft cartilage to hard bone without conferring fatigue damage over a lifetime of load cycles. However, the fine structure and mechanical properties of the osteochondral interface tissue remain unclear. Here, we identified an ultrathin ∼20-30 μm graded calcified region with two-layered micronano structures of osteochondral interface tissue in the human knee joint, which exhibited characteristic biomolecular compositions and complex nanocrystals assembly.