Protocol for microindentation analysis of human cartilage and methacrylated gelatin hydrogels with varying stiffness in ATDC5 cell cultures.

Here, we present a protocol for evaluating mechanical properties of human cartilage specimens and methacrylated gelatin (GelMA) hydrogels with varying Young's moduli for cultures of ATDC5 chondrocytes using microindentation. We describe steps for preparing human cartilage specimens and hydrogels, culturing ATDC5 cells, and assessing the stiffness. This protocol was designed to facilitate reproducibility in biomechanical assays of chondrocytes.

Matrix stiffness aggravates osteoarthritis progression through H3K27me3 demethylation induced by mitochondrial damage.

Abnormal epigenetics is the initial factor of the occurrence and development of osteoarthritis (OA), and abnormal mechanical load is a key pathogenic factor of OA. However, how abnormal mechanical load affects chondrocyte epigenetics is unclear. Chondrocytes reportedly respond to mechanics through the extracellular matrix (ECM), which has a role in regulating epigenetics in various diseases, and mitochondria are potential mediators of communication between mechanics and epigenetics.

Hypermethylation of Bmp2 and Fgfr2 Promoter Regions in Bone Marrow Mesenchymal Stem Cells Leads to Bone Loss in Prematurely Aged Mice.

Osteoporosis is an age-related, systemic skeletal disease that poses a significant public health challenge in contemporary society. Development at the epigenetic level is emerging as an important pathogenic mechanism of osteoporosis. Despite indications of a robust association between DNA methylation and osteoporosis development, a comprehensive understanding of the specific role of DNA methylation in osteoporosis remains limited.

A New Method to Predict Postoperative Stem Anteversion in Total Hip Arthroplasty for Developmental Dysplasia of the Hip.

Background: Preoperative evaluation of femoral anteversion to predict postoperative stem anteversion aids the selection of an appropriate prosthesis and optimizes the combined anteversion in total hip arthroplasty (THA) for developmental dysplasia of the hip (DDH). The conventional prediction methods are based on the femoral anteversion measurement at the location of the femoral head and/or neck. However, varied differences between femoral anteversion and postoperative stem anteversion were demonstrated.

A Radiographic Analysis of Coronal Morphological Parameters of Lower Limbs in Chinese Non-knee Osteoarthritis Populations.

Objectives: Analyzing the lower limb coronal morphological parameters in populations without knee osteoarthritis (KOA) holds significant value in predicting, diagnosing, and formulating surgical strategies for KOA. This study aimed to comprehensively analyze the variability in these parameters among Chinese non-KOA populations, employing a substantial sample size.

Methods: A cross-sectional retrospective analysis was performed on the Chinese non-KOA populations (n = 407; 49.

Cell-free fat extract-loaded microneedles attenuate inflammation-induced apoptosis and mitochondrial damage in tendinopathy.

Existing clinical treatments for tendinopathy mainly focus on reducing pain, whereas inhibiting or reversing disease progression remains challenging. Local therapeutic drugs, such as glucocorticoids, cause adverse effects on the metabolism of tendon tissues and injection-related complications. Therefore, new administration modalities for tendinopathy need to be developed.

Pre-Surgery Hip-Knee-Ankle Angle and Weightbearing Line Percentage Are Nearly Perfectly Correlated to the Miniaci Angle When Planning Open Wedge High Tibial Osteotomies.

Purpose: To investigate the conversion formulas between the Miniaci angle, presurgery parameters, and changes in presurgery parameters in open-wedge high tibial osteotomy (OWHTO), including hip-knee-ankle (HKA) angle, weightbearing line (WBL) percentage, mechanical medial proximal tibial angle (mMPTA), ΔHKA angle, ΔWBL percentage, ΔmMPTA, and other parameters.

Methods: From January 2012 to December 2019, 247 lower limbs of 144 patients with medial unicompartmental knee osteoarthritis combined with proximal tibia vara were enrolled. Inclusion criteria were adults, medial unicompartmental knee osteoarthritis, Kellgren-Lawrence classification grade ≤ III, mMPTA ≤ 85°, normal mechanical lateral distal femoral angle (85°-90°), and patella facing anterior in the bipedal standing position.

Use of a Gigli Saw as a Substitute Osteotomy Tool When Oscillating Saw Malfunctions Occur During Hip Arthroplasty.

Objective: The oscillating saw has some inherent disadvantages, such as notch formation and blood splash. The objective is to introduce the Gigli saw as a substitute osteotomy tool when oscillating saw malfunctions occur during surgery.

Methods: During our retrospective study, 120 patients (120 hips) who underwent primary total hip arthroplasty (THA) because of femoral neck fracture, femoral head necrosis, developmental hip dysplasia (Crowe I), or primary osteoarthritis between October 2017 and April 2020 at our institute were included.

Irisin promotes fracture healing by improving osteogenesis and angiogenesis.

Background: Osteogenesis and angiogenesis are important for bone fracture healing. Irisin is a muscle-derived monokine that is associated with bone formation.

Methods: To demonstrate the effect of irisin on bone fracture healing, closed mid-diaphyseal femur fractures were produced in 8-week-old C57BL/6 mice.

Application of a novel osteotomy instrumentation as a substitute tool in total hip arthroplasty.

Background: Mechanical failure, power shortage, and inadvertent contamination of the oscillating saw occasionally occurs in actualizing femoral neck osteotomy during total hip arthroplasty (THA); however, no appropriate alternative solution is currently available. This study aimed to introduce a novel osteotomy instrumentation (fretsaw, jig, cable passer hook) as a substitute tool while the oscillating saw was unavailable during THA.

Methods: This study included 40 patients (40 hips) who underwent femoral neck osteotomy during primary THA using the new osteotomy instrumentation (n = 20) and the oscillating saw (n = 20).

A novel revision system for complex pelvic defects utilizing 3D-printed custom prosthesis.

Background: Thus far, the hip revision surgery has been widely used and promoted, and the technology has been constantly innovated, such as tissue engineering, 3D printing prosthesis, etc. However, traditional standardized prosthesis, allograft, autograft, bone cement and reinforcing ring are still the main treatment methods in the mainstream pelvic defects classification systems for hip revision. In addition, the mainstream classification systems are still mainly focus on the peri-acetabulum, but less on the large-scale complex pelvic defects that widely affecting the regions far away from the acetabulum, which also have a significant impact on the holistic biomechanical properties of pelvis.

Associations of osteoclastogenesis and nerve growth in subchondral bone marrow lesions with clinical symptoms in knee osteoarthritis.

Background/objective: Subchondral bone marrow lesions (BMLs) are common magnetic resonance imaging (MRI) features in joints affected by osteoarthritis (OA), however, their clinical impacts and mechanisms remain controversial. Thus, we aimed to investigate subchondral BMLs in knee OA patients who underwent total knee arthroplasty (TKA), then evaluate the associations of osteoclastogenesis and nerve growth in subchondral BMLs with clinical symptoms.

Methods: Total 70 patients with primary symptomatic knee OA were involved, then separated into three groups based on MRI (without BMLs group, n ​= ​14; BMLs without cyst group, n ​= ​37; BMLs with cyst group, n ​= ​19).

Positive Correlation Between the Femur Neck Shaft and Anteversion Angles: A Retrospective Computed Tomography Analysis in Patients With Developmental Dysplasia of the Hip.

Background: This study aimed to explore the anatomical correlation between the femoral neck shaft angle (NSA) and femoral anteversion angle (AA) in patients with developmental dysplasia of the hip based on the Crowe classification and provide a novel method to estimate the femoral AA on anteroposterior pelvic radiographs.

Methods: A total of 208 patients with dysplastic hips who underwent total hip arthroplasty at our institution were retrospectively included. Preoperative physiological AA and NSA were determined via 3-dimensional computed tomography.

[Semi-automated measurement and analysis of three-dimensional acetabular orientation in asymptomatic population and patients of developmental dysplasia of the hip].

Objective: To evaluate the three-dimensional acetabular orientation in asymptomatic population and patients of developmental dysplasia of the hip (DDH) using a semi-automated measurement software, which provides data for the differential diagnosis, surgical planning, surgical instrument design, and postoperative evaluation of hip related diseases.

Methods: Eighty-four cases of CT data in asymptomatic population (asymptomatic group) and 47 cases of CT data in DDH patients (DDH group) were collected. There was no significant difference in gender and age (including age of male and female subgroups) between the two groups ( <0.

Osteocyte Apoptosis Contributes to Cold Exposure-induced Bone Loss.

Emerging evidence indicates that bone mass is regulated by systemic energy balance. Temperature variations have profound effects on energy metabolism in animals, which will affect bone remodeling. But the mechanism remains unclear.

A novel efficient and precise technique for removing acetabular osteophytes in patients undergoing total hip arthroplasty: the SH-9Hospital acetabular edge file.

Background: Total hip arthroplasty (THA) is frequently performed in patients with end-stage hip disease. Periacetabular osteophytes are common during THA; however, these osteophytes should be removed intraoperatively to avoid potential impingement between osteophytes and femoral prostheses and decrease dislocation risk. There are no current standard procedures or surgical technique criteria to remove these osteophytes.

Abnormal subchondral trabecular bone remodeling in knee osteoarthritis under the influence of knee alignment.

Objective: This study aimed to investigate the abnormal subchondral trabecular bone (STB) remodeling in knee osteoarthritis (OA) under the influence of knee alignment [hip-knee-ankle (HKA) angle].

Design: Forty-one patients with knee OA underwent radiographic examination before total knee arthroplasty (TKA) for the measurement of HKA angle. Tibial plateau specimens obtained during TKA were used for histomorphometric analyses to assess STB remodeling and cartilage degradation.

Lateral tibial intercondylar eminence is a reliable reference for alignment correction in high tibial osteotomy.

Purpose: The purpose of the study is to determine whether the lateral tibial intercondylar eminence (LTIE) is a reliable reference for alignment correction in high tibial osteotomy (HTO).

Methods: A total of 1954 consecutive standing whole-leg radiography (WLR) examinations of 1373 adult patients with knee osteoarthritis between 2012 and 2019 were reviewed retrospectively; 145 patients were included, 53 males and 92 females, with a mean age of 63.3 years.

Verification and clinical translation of a newly designed "Skywalker" robot for total knee arthroplasty: A prospective clinical study.

Objective: To evaluate accuracy of an innovative "Skywalker" system, a newly designed, robot-assisted operation system for orthopaedics via a clinical trial at knee joint.

Methods: We conducted a prospective analysis of the clinical data of 31 patients who underwent total knee arthroplasty assisted by the "Skywalker" robot (Microport, Suzhou, China) from June 2020 to January 2021. Five male patients and 26 female patients aged 69.

Three-dimensional printing-based personalized limb salvage and reconstruction treatment of pelvic tumors.

Background And Objectives: The treatment of pelvic tumors is widely recognized to be challenging. The purpose of this study was to evaluate the efficacy of personalized three-dimensional (3D) printing-based limb salvage and reconstruction treatment for pelvic tumors.

Methods: Twenty-eight pelvic tumor patients were enrolled.

Manipulation under anaesthesia versus lysis of adhesions for arthrofibrosis of the knee: a 6-month randomized, multicentre, non-inferiority comparative effectiveness protocol.

Background: Recent studies show similar outcomes between lysis of adhesions (LOA) and manipulation under anaesthesia (MUA) in patients with arthrofibrosis within 3 to 6 months after arthroscopic knee procedures. As MUA offers positive efficacy with less expense and more convenience, the first consideration in clinical practice shifting to MUA may save much medical cost when MUA is non-inferior to surgery. There is a lack of evidence comparing the clinical outcomes of these two surgical techniques.

A novel and efficient surgical knotting technique for high-tension closures.

Background: The closure of high-tension incisions without any assistance can be difficult and challenging for surgeons. A common practice is to fix the first knot with a clamp and then tie a reverse locking knot; however, this practice has certain disadvantages. The aim of this study was to introduce a novel and efficient surgical knotting technique with various advantages.

Subchondral Trabecular Microstructure and Articular Cartilage Damage Variations Between Osteoarthritis and Osteoporotic Osteoarthritis: A Cross-sectional Cohort Study.

Osteoporotic osteoarthritis (OP-OA) is a specific type of OA. In this study, we aimed to assess the subchondral plate and rod microstructural differences between OA and OP-OA patients by using an individual trabeculae segmentation (ITS) system and to analyze the relationships between subchondral microstructures and cartilage damage in OA and OP-OA patients. Overall, 31 femoral heads were included in this study, which included 11 samples with OA and 13 samples with OP-OA; the normal control (NC) group contained 7 healthy femoral heads.

Osteoblast and Osteoclast Activity Affect Bone Remodeling Upon Regulation by Mechanical Loading-Induced Leukemia Inhibitory Factor Expression in Osteocytes.

Purpose: Bone remodeling is affected by mechanical stimulation. Osteocytes are the primary mechanical load-sensing cells in the bone, and can regulate osteoblast and osteoclast activity, thus playing a key role in bone remodeling. Further, bone mass during exercise is also regulated by Leukemia inhibitory factor (LIF).