Intraoperative radiographic analysis and adjustment of the optimal position of plate in high tibial osteotomy.

BACKGROUND: When high tibial osteotomy is performed for genu varus deformity, it is not easy to determine the accurate placement of the plate. PURPOSE: To determine a simple way to assess the position of the plate, to provide more effective mechanical support and to reduce the risk of implant rupture and vascular injury. MATERIAL AND METHODS: Two human anatomical marks, the patellar ligament and semimembranosus, were connected and divided into four parts to identify points Ⅰ, Ⅱ, and Ⅲ. These points determined the areas for Tomofix placement: anterior, anterolateral, and lateral. Simulated internal fixation placed hole B of Tomofix at points Ⅰ (anterior), Ⅱ (anterolateral), and Ⅲ (lateral). We analyzed the pointing direction of the locking screws in Tomofix holes on MRI to assess potential injury risk to the popliteal neurovascular bundle. RESULTS: In the X-ray: holes B and C appeared as the plate in the anterior, only hole C appeared as the plate in the anterolateral, and none of the holes appeared as the plate in the lateral. In the general view of the sawbones, the screw pointed towards the popliteal neurovascular bundle when the plate was in the anterior. CONCLUSION: If a small number of holes on the plate is visible under fluoroscopy, then several lateral positions of the plate can be obtained; the direction of the screw tunnel tends to deviate from the popliteal neurovascular bundle with the posterior position of the plate.

Laser stripe segmentation and centerline extraction based on 3D scanning imaging.

Ambient noise and illumination inhomogeneity will seriously affect the high-precision measurement of structured light 3D morphology. To overcome the influences of these factors, a new, to the best of our knowledge, sub-pixel extraction method for the center of laser stripes is proposed. First, an automatic segmentation model of structured light stripe based on the UNet deep learning network and level set is constructed. Coarse segmentation of laser stripes using the UNet network can effectively segment more complex scenes and automatically obtain a prior shape information. Then, the prior information is used as a shape constraint for fine segmentation of the level set, and the energy function of the level set is improved. Finally, the stripe normal field is obtained by calculating the stripe gradient vector, and the center of the stripe is extracted by fusing the gray center of gravity method according to the normal direction of the stripe distribution. The experimental results show that the average width error of different rows of point cloud data of workpieces with different widths is less than 0.3 mm, and the average repeatability extraction error is less than 0.2 mm.

Clinical efficacy and feasibility of laser correction technology with an ordinary laser pen and surgical instrument box in open-wedge high tibial osteotomy.

BACKGROUND: The clinical outcomes of open-wedge high tibial osteotomy (OWHTO) for medial knee osteoarthritis primarily depend on the corrective precision. The present study aimed to determine the efficacy and feasibility of laser correction technology with an ordinary laser pen and surgical instrument box. METHODS: This prospective and randomized trial included 71 patients randomly divided into laser (n = 36) and traditional groups (n = 35). In the laser group, the hip centre, knee (Fujisawa point), and ankle centre were located preoperatively using the surgical instrument box lid. The leg was aligned with an ordinary laser pen. In the traditional group, the lower limb alignment was corrected by a metal cable. Radiation exposure, operative time, and rate of outliers (lower limb force line does not pass through 62-66% of the lateral tibial plateau) were evaluated. The visual analogue scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were recorded. After 24 months, the femoral tibial angle (FTA), medial proximal tibial angle (MPTA), and posterior slope angle (PSA), were recorded. The Kaplan-Meier method was used to evaluate the survival time of affected knees, and postoperative complications were recorded. RESULTS: The radiation exposure, operative time and rate of outliers were lower in the laser correction group (P < 0.05). Six months postoperatively, the VAS and WOMAC scores were significantly improved in both groups (P < 0.001). At 24 months, the FTA, MPTA, and PSA were corrected in both groups (P < 0.001). There were no differences in the postoperative knee survival time from OWHTO to knee arthroplasty between the groups or postoperative complications (P = 0.53; P = 0.61). CONCLUSIONS: Laser correction technology can effectively reduce radiation exposure, the operative time, and the rate of outliers (trial identification number (retrospectively registered): ChiCTR2200060480; date of register: 03/06/2022).

In situ cell electrospun using a portable handheld electrospinning apparatus for the repair of wound healing in rats.

Slow or non-healing wounds caused by full-thickness skin wounds of various origins have become a difficult challenge in clinical wound treatment. In particular, large full-thickness skin wounds often lead to serious chronic skin wounds that do not heal. Electrospinning technology and stem cell treatment for wound repair have attracted much attention due to its unique advantages. In the current study， we electrospun polyvinyl alcohol (PVA) and bone marrow-derived stem cells (BMSCs) by a handheld electrospinning device, the distribution and interaction of cells and fibres were determined by light and electron microscopy and the cell viability and proliferation were determined by live/dead cell staining. The tissues were analysed by histology with Haematoxylin and Eosin (H&E) and Masson staining and immunohistochemical staining. We found that the fibres were distributed uniformly and BMSCs were distributed between the fibres. Cytotoxicity and cell proliferation tests proved its good biocompatibility. Histological staining shows it can accelerate wound healing and appendages regeneration by promoting granulation tissue repair. The instant PVA/stem cell fibres prepared by a handheld electrospinning device strongly promote the repair of full-thickness skin wounds in rats. The proposed electrospinning technology is expected to have great potential in household, outdoor and battlefield first aid.

Intra-Articular Platelet-Rich Plasma Combined With Hyaluronic Acid Injection for Knee Osteoarthritis Is Superior to Platelet-Rich Plasma or Hyaluronic Acid Alone in Inhibiting Inflammation and Improving Pain and Function.

PURPOSE: To evaluate the effectiveness and explore the therapeutic mechanisms of platelet-rich plasma (PRP) combined with hyaluronic acid (HA) as a treatment for knee osteoarthritis (KOA). METHODS: In total, 122 knees were randomly divided into HA (34 knees), PRP (40 knees), and PRP+HA (48 knees) groups. Platelet densities in whole blood and PRP were examined using Wright-Giemsa staining. Visual analogue scale, Lequesne, Western Ontario and McMaster Universities Osteoarthritis Index, Lysholm scores, and postoperative complications were evaluated. High-frequency color Doppler imaging was used to observe the synovium and cartilage. Enzyme-linked immunosorbent assays were used to quantify interleukin-1ß, tumor necrosis factor-α, matrix metalloproteinase-3, and tissue inhibitor of metalloproteinase-1 levels in synovial fluid. RESULTS: The platelet density in PRP was 5.13-times that in whole blood (P = .002). At 24 months, pain and function scores in the PRP+HA group were better than those in the HA-alone and PRP-alone groups (Ppain = .000; Pfunction = .000). At 6 and 12 months, synovial hyperplasia in the PRP and PRP+HA groups was improved (P < .05). After 6 and 12 months, the synovial peak systolic velocity, synovial end-diastolic velocity, systolic/diastolic ratio, and resistance index were improved in the PRP+HA group (P < .05). Complications were greatest in the PRP group (P = .008). After 6 and 12 months, interleukin-1ß, tumor necrosis factor-α, matrix metalloproteinase-3, and tissue inhibitor of metalloproteinase-1 in the PRP and PRP+HA groups decreased (P < .05), with more apparent inhibition in the PRP+HA group (P < .05). CONCLUSIONS: PRP combined with HA is more effective than PRP or HA alone at inhibiting synovial inflammation and can effectively improve pain and function and reduce adverse reactions. Its mechanism involves changes in the synovium and cytokine content. LEVEL OF EVIDENCE: Level II, Prospective cohort study.

Transcriptomic analysis reveals mechanism of light-sensitive albinism in tea plant Camellia sinensis 'Huangjinju'.

BACKGROUND: Camellia sinensis 'Huangjinju' is an albino tea variety developed recently in China. Young leaves of 'Huangjinju' demonstrate bright yellow when cultivated under natural sunlight, but regreens under reduced light intensity. To elucidate the physiological and molecular mechanisms of this light-sensitive albinism, we compared leaf pigmentation, metabolites, cellular ultrastructure and transcriptome between plants cultured under natural sunlight and shade. RESULTS: Shading treatment doubled the chlorophyll concentration and regreened albino leaves; carotenoid also increased by 30%. Electron microscopy analyses showed that chloroplast not only increased in number but also in size with a complete set of components. In addition, regreened leaves also had a significantly higher concentration of polyphenols and catechins than albino leaves. At transcriptomic level, a total of 507 genes were differentially expressed in response to light condition changes. The most enriched pathways include light harvest protein complex, response to stimuli, oxidation-reduction process, generation of precursor metabolites and energy response. CONCLUSION: The integrated strategy in this study allows a mechanistic understanding of leaf albinism in light-sensitive tea plants and suggested the regulation of gene networks involved in pigmentation and protein processing. Results from this study provide valuable information to this area and can benefit the domestication and artificial breeding to develop new albino tea varieties.

A Composite Tissue Engineered Bone Material Consisting of Bone Mesenchymal Stem Cells, Bone Morphogenetic Protein 9 (BMP9) Gene Lentiviral Vector, and P3HB4HB Thermogel (BMSCs-LV-BMP9-P3HB4HB) Repairs Calvarial Skull Defects in Rats by Expression of Osteogenic Factors.

BACKGROUND Bone tissue engineering has been proven to be an appropriate approach for treating bone defects. This study aimed to investigate the effects and mechanism of a composite tissue engineered bone material consisting of bone mesenchymal stem cells (BMSCs), bone morphogenetic protein (BMP9) gene lentiviral vector, and P3HB4HB thermogel (BMSCs-LV-BMP9-P3HB4HB) on calvarial skull defects in rats. MATERIAL AND METHODS LV-BMP9 viral vector was structured and infected to BMSCs-P3HB4HB composite scaffold, which was named as BMSCs-P3HB4HB composite bone repair material. Adipogenic differentiation was determined by oil-red O (ORO) and alkaline phosphatase (ALP) staining. Osteogenic differentiation was measured using Alizarin red staining. Cell viability was examined using Cell-Counting Kit-8 (CCK-8) assay. Protein expression of osteogenic factors, including BMP9, runt-related transcription factor 2 (RUNX2), osteocalcin (OCN), osteopontin (OPN), and osterix (OSX), was detected with Western blot assay and immunohistochemistry. mRNA of these osteogenic factors was examined by RT-PCR. Histological changes were examined with hematoxylin and eosin (H&E) and Masson's trichrome staining. Bone repair was measured using micro-computed tomography (micro-CT). RESULTS BMSCs and LV-BMP9-infected BMSCs demonstrated adipogenic and osteogenic differentiation potential. BMSCs-P3HB4HB scaffold demonstrated good cell-tissue compatibility. BMSCs-LV-BMP9-P3HB4HB exhibited significantly higher osteogenic ability and cell viability of BMSCs compared to BMSCs-LV-P3HB4HB (p<0.05). BMSCs-LV-BMP9-P3HB4HB significantly promoted osteogenic factors (RUNX2, OCN, OPN, and OSX) expression compared to the BMSCs-LV-P3HB4HB group (p<0.05) in both BMSCs and in calvarial defect rats. BMSCs-LV-BMP9-P3HB4HB demonstrated stronger repair ability. BMSCs-LV-BMP9-P3HB4HB significantly alleviated pathological injury and increased collagen fiber production compared to the BMSCs-LV-P3HB4HB group (p<0.05). CONCLUSIONS BMSCs-LV-BMP9-P3HB4HB composite bone repair material can effectively repair injured skull tissues of calvarial defect rats through triggering osteogenic factors expression. The present generated bone repair material may have applications in tissue engineering in regeneration of bone defects.

Correlation between the efficacy of stem cell therapy for osteonecrosis of the femoral head and cell viability.

BACKGROUND: Osteonecrosis of the femoral head (ONFH) is a common disease that greatly affects the quality of life of patients. Repair of the necrotic area is key to successful treatment. Currently, the combination of stem cell transplantation and decompression is used clinically to promote the repair of necrotic areas based on the characteristics of stem cells. However, a considerable number of patients do not achieve a satisfactory outcome in terms of repair of the femoral head necrotic area, and it is very important to determine the reasons for the poor curative effect. The aim of this study was to investigate the correlation between stem cell viability and the repair efficacy of stem cell therapy combined with core decompression for early-stage ONFH. METHODS: A total of 30 patients with idiopathic ONFH underwent core decompression combined with autologous stem cell transplantation. The Harris hip score (HHS) and difference in necrosis area before and after surgery were measured. The mean repair ratio was set as the threshold to divide the patients into group A (ratio above the mean) and group B (ratio below the mean). The ultrastructure, proliferative capacity, and multidirectional differentiation ability were compared between the groups. RESULTS: At 9 months after surgery, the HHS and magnetic resonance imaging (MRI) findings improved by varying degrees. Based on the mean repair ratio of (62.2 ± 27.0)%, the threshold for dividing the patients into groups A and B was set to 62.2%. Better repair (group A) was associated with more rapid proliferation and a healthier ultrastructure. The cells in group A showed stronger specific staining signifying osteogenic and chondrogenic differentiation; alkaline phosphatase (ALP) activity, an indicator of osteogenic differentiation, was higher in group A than in group B (OD, 2.39 ± 0.44 and 1.85 ± 0.52; p <  0.05). CONCLUSIONS: The quality of implanted stem cells is closely related to treatment efficacy and determines whether the defective self-repair in the necrotic area can be corrected to enhance repair and thus achieve the desired therapeutic outcome. TRIAL REGISTRATION: The trial registration number: ChiCTR-ORC-17011698 (retrospectively registered at 2017-06-19).

Osteoblastic differentiation of stem cells induced by graphene oxide-hydroxyapatite-alginate hydrogel composites and construction of tissue-engineered bone.

This study aimed to investigate the effect of graphene oxide (GO)-hydroxyapatite (HA)-sodium alginate (SA) composite application in the field of bone tissue engineering. Four scaffold groups were established (SA-HA, SA-HA-0.8%GO, SA-HA-1.0%GO and SA-HA-1.2%GO) and mixed with bone marrow mesenchymal stem cells (BMSCs). Hydrogel viscosity was measured at room temperature, and after freeze-drying and Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) to detect substance crystallinity, the printability of each hydrogel type was measured with a printing grid. Scanning electron microscopy (SEM) was used to observe the internal microstructure of the scaffolds and to evaluate the growth and proliferation of cells on the scaffold. A hollow cylinder was printed to compare the forming effect of the hydrogel bioinks, and cell-hydrogel composites were implanted under the skin of nude mice to observe the effect of the hydrogels on osteogenesis in vivo. Increased GO concentrations led to reduced scaffold degradation rates, increased viscosity, increased printability, increased mechanical properties, increased scaffold porosity and increased cell proliferation rates. In vivo experiments showed that hematoxylin and eosin (HE) staining, Alizarin red staining, alkaline phosphatase staining and collagen type I immunohistochemical staining increased as the implantation time increased. These results demonstrate that GO composites have high printability as bioinks and can be used for bioprinting of bone by altering the ratio of the different components.

Development and Application of a No-Clog Surgical Suction Tip Using 3D Printing Technology.

BACKGROUND Clogging of the suction tip frequently occurs during orthopedic surgery. We developed a novel anti-clog suction tip using 3D printing technology to improve orthopedic surgery efficiency. MATERIAL AND METHODS We studied the root causes of obstructions in suction tips currently employed in orthopedic surgery during actual surgical cases. CAD software and 3D printer was used to design, modify, and print the novel suction tip. The frequency of clogging, the frequency of replacement of the suction tip, the time lost in replacing suction tips or connecting tubes, surgical duration, intraoperative surgical blood loss, and the satisfaction scores for the suction tips as rated by the surgeons were compared between the novel suction tip and the conventional suction tip. Comparisons were made first in laboratory experiments using a simulant liquid and then during total hip replacement surgeries. RESULTS In the simulant liquid experiments, the novel suction tips showed significantly reduced frequency of complete clogging and decreased time spent removing all fluid in comparison to the conventional suction tips (p<0.05). In the clinical trials, the novel suction tips exhibited significantly reduced frequency of complete clogging, shorter surgical duration, and reduced intraoperative surgical blood loss compared to the conventional suction tips (p<0.05). Surgeon satisfaction scores were higher for the novel tips than for the conventional tips (p<0.05). CONCLUSIONS Our surgeon-designed and -produced surgical suction tip utilizing 3D desktop printing technology was highly effective in resolving the problem of clogged suction tips during orthopedic surgery and yielded high surgeon satisfaction.

Construction of an adherence rating scale for exercise therapy for patients with knee osteoarthritis.

BACKGROUND: Knee osteoarthritis (KOA) is one of the most common chronic diseases in the elderly and is the primary cause of the loss of motor function and disability in this population. Exercise therapy is a core, basic and matureand treatment method of treating patients with KOA. Exercise therapy is "strongly recommended" or "recommended" in the diagnosis and treatment guidelines of osteoarthritis in many countries, and most scholars advocate exercise therapy as the preferred rehabilitation method for KOA patients. However, poor long-term adherence is a serious problem affecting the therapeutic effect of this mature treatment. The objective of this study was to construct a concise and practical adherence rating scale (ARS) based on the exercise therapy adherence prediction model in patients with knee osteoarthritis. METHODS: A binary logistic regression model was established, with the adherence of 218 cases of KOA patients as the dependent variable. The patients' general information, exercise habits, knowledge, attitude, and exercise therapy were independent variables. The regression coefficients were assigned to various variables in the model, and the ARS was constructed accordingly. Receiver operating characteristic curves and curve fitting were used to analyse the effect of the ARS in predicting the adherence and to determine the goodness of fit for the adherence. The external validity of the ARS was examined in a randomized controlled trial. RESULTS: The construction of the adherence model and the ARS included the following variables: age (1 point), education level (1 point), degree of social support (2 points), exercise habits (3 points), knowledge of KOA prevention and treatment (2 points), degree of care needed to treat the disease (1 point), familiarity with exercise therapy (4 points) and treatment confidence (3 points). The critical value of the total score of the ARS was 6.50, with a sensitivity of 87.20% and a specificity of 76.34%. CONCLUSIONS: A KOA exercise therapy adherence model and a simple and practical ARS were constructed. The ARS has good internal validity and external validity and can be used to evaluate the adherence to exercise therapy in patients with KOA.

Three dimensional printing technology and materials for treatment of elbow fractures.

PURPOSE: 3D printing is a rapid prototyping technology that uses a 3D digital model to physically build an object. The aim of this study was to evaluate the peri-operative effect of 3D printing in treating complex elbow fractures and its role in physician-patient communication and determine which material is best for surgical model printing. METHOD: Forty patients with elbow fractures were randomly divided into a 3D printing-assisted surgery group (n = 20) and a conventional surgery group (n = 20). Surgery duration, intra-operative blood loss, anatomic reduction rate, incidence of complications and elbow function score were compared between the two groups. The printing parameters, the advantages and the disadvantages of PLA and ABS were also compared. The independent-samples t-test was used to compare the data between groups. A questionnaire was designed for orthopaedic surgeons to evaluate the verisimilitude, the appearance of being true or real, and effectiveness of the 3D printing fracture model. Another questionnaire was designed to evaluate physician-patient communication effectiveness. RESULTS: The 3D group showed shorter surgical duration, lower blood loss and higher elbow function score, compared with the conventional group. PLA is an environmentally friendly material, whereas ABS produce an odour in the printing process. Curling edges occurred easily in the printing process with ABS and were observed in four of ten ABS models but in only one PLA model. The overall scores given by the surgeons about the verisimilitude and effectiveness of the 3D model were relatively high. Patient satisfaction scores for the 3D model were higher than those for the 2D imaging data during physician-patient discussions. CONCLUSION: 3D-printed models can accurately depict the anatomic characteristics of fracture sites, help surgeons determine a surgical plan and represent an effective tool for physician-patient communication. PLA is more suitable for desktop fused deposition printing in surgical modeling applications.

Both Talin-1 and Talin-2 correlate with malignancy potential of the human hepatocellular carcinoma MHCC-97 L cell.

BACKGROUND: Talin-1 (TLN-1) and TLN-2 are implicated in many cellular processes, but their roles in hepatocellular carcinoma (HCC) remain unclear. This study aimed to assess cell cycle distribution, anoikis, invasion and migration in human HCC MHCC-97 L cells. METHODS: MHCC-97 L cells, which highly express TLN-1, were transduced with TLN-1 shRNA (experimental group) or scramble shRNA (negative control group); non-transduced MHCC-97 L cells were used as blank controls. TLN-1 and TLN-2 mRNA and protein levels were detected by real-time RT-PCR and western blot, respectively. Then, cell cycle distribution and anoikis were assessed by flow cytometry. In addition, migration and invasion abilities were assessed using Transwell and cell scratch assays. Finally, a xenograft nude mouse model was established to further assess cell tumorigenicity. RESULTS: Compared with the blank and negative control groups, TLN-1/2 mRNA and protein levels were significantly reduced in the experiment group. TLN-1/2 knockdown cells showed significantly more cells in the G0/G1 phase (79.24%) in comparison with both blank (65.36%) and negative (62.69%) control groups; conversely, less cells were found in G2/M and S phases in the experimental group compared with controls. Moreover, anoikis was enhanced (P < 0.05), while invasion and migration abilities were reduced (P < 0.05) in TLN-1/2 knockdown cells compared with controls. TLN-1/2 knockdown inhibited MHCC-97 L cell migration (Percentage of wound healing area: experimental group: 32.6 ± 0.7% vs. negative controls: 50.1 ± 0.6% and blank controls: 53.6 ± 0.6%, both P < 0.01). Finally, the tumors obtained with TLN-1/2 knockdown cells were smaller (P < 0.05) compared with controls. CONCLUSION: Both TLN-1 and TLN-2 levels correlate with tumorigenicity in human HCC, indicating that these molecules constitute important molecular targets for the diagnosis and/or treatment of HCC.

Bio-electrospraying is a safe technology for delivering human adipose-derived stem cells.

Bio-electrospraying (BES) is a technique for directly jetting living cells that has significant implications for tissue engineering and regenerative medicine. However, the effect of BES on human adipose-derived stem cells (hASCs) remains unknown. Here, we show that an hASC suspension was successfully electrosprayed via a continuous, stable and linearly directed electrospray at 10 kV and at 3 ml/h. Morphological observations and Trypan Blue and CCK-8 assays revealed that the cells remained viable and proliferated at a rate similar to that of the controls (0 kV). However, at 20 kV, BES became unstable and cell viability was reduced. Moreover, hASCs electrosprayed at 10 kV retained their multilineage potential, successfully differentiating into chondrogenic, osteogenic and neurogenic lineages. Thus, BES does not significantly affect cell morphology, viability or multipotency.

Cementless bilateral synchronous total hip arthroplasty in ankylosing spondylitis with hip ankylosis.

PURPOSE: This study was a retrospective analysis of early and mid-term clinical effects and perioperative management of cementless bilateral synchronous total hip arthroplasty (THA) in patients with ankylosing spondylitis (AS) with bilateral hip ankylosis. METHODS: Fifteen AS patients (30 hips) with bilateral hip ankylosis were managed with cementless bilateral synchronous THA. Surgical outcome was evaluated using the visual analogue scale (VAS), the range of motion and the Harris score. RESULTS: The mean follow-up period was 29.3 months. At the last follow-up visit, the VAS score decreased from 7.53 ± 0.99 before the operation to 2.40 ± 0.91. The Harris score increased from 24.8 ± 7.42 before the operation to 83.8 ± 4.61. The total range of motion increased from 78.73 ± 14.53 before the operation to 209.73 ± 16.19 after the operation. After the operation, there was one case of early hip dislocation, one case of femoral nerve stretch injury and one case of superficial incision infection. There were no cases of deep venous thrombosis. X-ray examinations did not show prosthetic loosening or displacement. CONCLUSION: AS patients with bilateral hip ankylosis can be treated with cementless bilateral synchronous THA, which could greatly improve hip joint function without significant complications. The clinical effects proved to be satisfactory.

Application of Metagenomic High-Throughput Sequencing in a Rare Case of Multisite Infection With Two Microorganisms After Total Knee Arthroplasty.

Postoperative deep infection is usually identified by microbial culture. However, frequent false-negative results have severely limited effective treatment. We report a rare case of intra-articular and paravertebral infection after total knee arthroplasty caused by Mycoplasma hominis and Ureaplasma urealyticum, with multiple negative microbial culture results. Eventually, the pathogens were identified using metagenomic high-throughput sequencing, and the patient was successfully treated with several "old" antibiotics. We analyze the clinical characteristics of this patient and systematically describe the application of high-throughput sequencing and antibiotics. [Orthopedics. 2024;47(1):e52-e56.].

Intelligent and Bioactive Osseointegration of the Implanted Piezoelectric Bone Cement with the Host Bone Is Realized by Biomechanical Energy.

Poly methyl methacrylate (PMMA) bone cement is widely used in orthopedic surgeries, including total hip/knee arthroplasty and vertebral compression fracture treatment. However, loosening due to bone resorption is a common mid-to-late complication. Therefore, developing bioactive bone cement that promotes bone growth and integration is key to reducing aseptic loosening. In this study, we developed a piezoelectric bone cement comprising PMMA and BaTiO3 with excellent electrobioactivity and further analyzed its ability to promote bone integration. Experiments demonstrate that the PMMA and 15 wt % BaTiO3 cement generated an open-circuit voltage of 37.109 V under biomimetic mechanical stress, which effectively promoted bone regeneration and interfacial bone integration. In vitro experiments showed that the protein expression levels of ALP and RUNX-2 in the 0.65 Hz and 20 min group increased by 1.74 times and 2.31 times. In vivo experiments confirmed the osteogenic ability of PMMA and 15 wt % BaTiO3, with the increment of bone growth in the non-movement and movement groups being 4.67 and 4.64 times, respectively, at the second month after surgery. Additionally, Fluo-4 AM fluorescence staining and protein blotting experiments verified that PMMA and 15 wt % BaTiO3 electrical stimulation promoted osteogenic differentiation of BMSCs by activating calcium-sensitive receptors and increasing calcium ion inflow by 1.41 times when the stimulation reached 30 min. Therefore, piezoelectric bioactive PMMA and 15 wt % BaTiO3 cement has excellent application value in orthopedic surgery systems where stress transmission is prevalent.