Objectives. This study was conducted to evaluate the cytokine-release kinetics of platelet-rich plasma (PRP) according to different activation protocols. Methods. Two manual preparation procedures (single-spin (SS) at 900 g for five minutes; double-spin (DS) at 900 g for five minutes and then 1500 g for 15 minutes) were performed for each of 14 healthy subjects. Both preparations were tested for platelet activation by one of three activation protocols: no activation, activation with calcium (Ca) only, or calcium with a low dose (50 IU per 1 ml PRP) of thrombin. Each preparation was divided into four aliquots and incubated for one hour, 24 hours, 72 hours, and seven days. The cytokine-release kinetics were evaluated by assessing PDGF, TGF, VEGF, FGF, IL-1, and MMP-9 concentrations with bead-based sandwich immunoassay. Results. The concentration of cytokine released from PRP varied over time and was influenced by various activation protocols. Ca-only activation had a significant effect on the DS PRPs (where the VEGF, FGF, and IL-1 concentrations were sustained) while Ca/thrombin activation had effects on both SS and DS PRPs (where the PDGF and VEGF concentrations were sustained and the TGF and FGF concentrations were short). The IL-1 content showed a significant increase with Ca-only or Ca/thrombin activation while these activations did not increase the MMP-9 concentration. Conclusion. The SS and DS methods differed in their effect on cytokine release, and this effect varied among the cytokines analysed. In addition, low dose of thrombin/calcium activation increased the overall cytokine release of the PRP preparations over seven days, relative to that with a calcium-only supplement or non-activation. Cite this article: Professor J. H. Oh. Cytokine-release kinetics of platelet-rich plasma according to various activation protocols. Bone Joint Res 2016;5:37–45. doi: 10.1302/2046-3758.52.2000540

Aims. To characterize the intracellular penetration of osteoblasts and osteoclasts by methicillin-resistant Staphylococcus aureus (MRSA) and the antibiotic and detergent susceptibility of MRSA in bone. Methods. Time-lapse confocal microscopy was used to analyze the interaction of MRSA strain USA300 with primary murine osteoblasts and osteoclasts. The effects of early and delayed antibiotic treatments on intracellular and extracellular bacterial colony formation and cell death were quantified. We tested the effects of cefazolin, gentamicin, vancomycin, tetracycline, rifampicin, and ampicillin, as well as agents used in surgical preparation and irrigation. Results. MRSA infiltrated bone-resident cells within 15 to 30 minutes. Penetration was most effectively prevented with early (i.e. 30 minutes) antibiotic administration. The combined administration of rifampicin with other antibiotics potentiated their protective effects against MRSA-induced cytotoxicity and most significantly reduced extracellular bacterial bioburden. Gentamicin-containing compounds were most effective in reducing intracellular MRSA bioburden. Of the surgical preparation agents evaluated, betadine reduced in vitro MRSA growth to the greatest extent. Conclusion. The standard of care for open fractures involves debridement and antibiotics within the first six hours of injury but does not account for the window in which bacteria penetrate cells. Antibiotics must be administered as early as possible after injury or prior to incision to prevent intracellular infestation. Rifampicin can potentiate the capacity of antibiotic regimens to reduce MRSA-induced cytotoxicity. Cite this article:Bone Joint Res. 2020;9(2):49–59

Aims. Tourniquets have potential adverse effects including postoperative thigh pain, likely caused by their ischaemic and possible compressive effects. The aims of this preliminary study were to determine if it is possible to directly measure intramuscular pH in human subjects over time, and to measure the intramuscular pH changes resulting from tourniquet ischaemia in patients undergoing knee arthroscopy. Methods. For patients undergoing short knee arthroscopic procedures, a sterile calibrated pH probe was inserted into the anterior fascial compartment of the leg after skin preparation, but before tourniquet inflation. The limb was elevated for three minutes prior to tourniquet inflation to 250 mmHg or 300 mmHg. Intramuscular pH was recorded at one-second intervals throughout the procedure and for 20 minutes following tourniquet deflation. Probe-related adverse events were recorded. Results. A total of 27 patients were recruited to the study. Mean tourniquet time was 21 minutes (10 to 56). Tourniquet pressure was 300 mmHg for 21 patients and 250 mmHg for six patients. Mean muscle pH prior to tourniquet inflation was 6.80. Muscle pH decreased upon tourniquet inflation, with a steeper fall in the first ten minutes than for the rest of the procedure. Change in muscle pH was significant after five minutes of tourniquet ischaemia (p < 0.001). Mean muscle pH prior to tourniquet release was 6.58 and recovered to 6.75 within 20 minutes following release. No probe related adverse events were recorded. Conclusion. It is possible to directly measure skeletal muscle pH in human subjects over time. Tourniquet ischaemia results in a decrease in human skeletal muscle pH over time during short procedures. Cite this article: Bone Joint Res 2021;10(6):363–369

Objectives. Platelet-rich fibrin matrix (PRFM) has been proved to enhance tenocyte proliferation but has mixed results when used during rotator cuff repair. The optimal PRFM preparation protocol should be determined before clinical application. To screen the best PRFM to each individual’s tenocytes effectively, small-diameter culture wells should be used to increase variables. The gelling effect of PRFM will occur when small-diameter culture wells are used. A co-culture device should be designed to avoid this effect. Methods. Tenocytes harvested during rotator cuff repair and blood from a healthy volunteer were used. Tenocytes were seeded in 96-, 24-, 12-, and six-well plates and co-culture devices. Appropriate volumes of PRFM, according to the surface area of each culture well, were treated with tenocytes for seven days. The co-culture device was designed to avoid the gelling effect that occurred in the small-diameter culture well. Cell proliferation was analyzed by water soluble tetrazolium-1 (WST-1) bioassay. Results. The relative quantification (condition/control) of WST-1 assay on day seven revealed a significant decrease in tenocyte proliferation in small-diameter culture wells (96 and 24 wells) due to the gelling effect. PRFM in large-diameter culture wells (12 and six wells) and co-culture systems induced a significant increase in tenocyte proliferation compared with the control group. The gelling effect of PRFM was avoided by the co-culture device. Conclusion. When PRFM and tenocytes are cultured in small-diameter culture wells, the gelling effect will occur and make screening of personalized best-fit PRFM difficult. This effect can be avoided with the co-culture device. Cite this article: C-H. Chiu, P. Chen, W-L. Yeh, A. C-Y. Chen, Y-S. Chan, K-Y. Hsu, K-F. Lei. The gelling effect of platelet-rich fibrin matrix when exposed to human tenocytes from the rotator cuff in small-diameter culture wells and the design of a co-culture device to overcome this phenomenon. Bone Joint Res 2019;8:216–223. DOI: 10.1302/2046-3758.85.BJR-2018-0258.R1

Objectives. Previous studies have evidenced cement-in-cement techniques as reliable in revision arthroplasty. Commonly, the original cement mantle is reshaped, aiding accurate placement of the new stem. Ultrasonic devices selectively remove cement, preserve host bone, and have lower cortical perforation rates than other techniques. As far as the authors are aware, the impact of ultrasonic devices on final cement-in-cement bonds has not been investigated. This study assessed the impact of cement removal using the Orthosonics System for Cemented Arthroplasty Revision (OSCAR; Orthosonics) on final cement-in-cement bonds. Methods. A total of 24 specimens were manufactured by pouring cement (Simplex P Bone Cement; Stryker) into stainless steel moulds, with a central rod polished to Stryker Exeter V40 specifications. After cement curing, the rods were removed and eight specimens were allocated to each of three internal surface preparation groups: 1) burr; 2) OSCAR; and 3) no treatment. Internal holes were recemented, and each specimen was cut into 5 mm discs. Shear testing of discs was completed by a technician blinded to the original grouping, recording ultimate shear strengths. Scanning electron microscopy (SEM) was completed, inspecting surfaces of shear-tested specimens. Results. The mean shear strength for OSCAR-prepared specimens (33.6 MPa) was significantly lower than for the control (46.3 MPa) and burr (45.8 MPa) groups (p < 0.001; one-way analysis of variance (ANOVA) with Tukey’s post hoc analysis). There was no significant difference in shear strengths between control and burr groups (p = 0.57). Scanning electron microscopy of OSCAR specimens revealed evidence of porosity undiscovered in previous studies. Conclusion. Results show that the cement removal technique impacts on final cement-in-cement bonds. This in vitro study demonstrates significantly weaker bonds when using OSCAR prior to recementation into an old cement mantle compared with cement prepared with a burr or no treatment. This infers that care must be taken in surgical decision-making regarding cement removal techniques used during cement-in-cement revision arthroplasty, suggesting that the risks and benefits of ultrasonic cement removal need consideration. Cite this article: A. Liddle, M. Webb, N. Clement, S. Green, J. Liddle, M. German, J. Holland. Ultrasonic cement removal in cement-in-cement revision total hip arthroplasty: What is the effect on the final cement-in-cement bond? Bone Joint Res 2019;8:246–252. DOI: 10.1302/2046-3758.86.BJR-2018-0313.R1

Objectives. Platelet-rich plasma (PRP) is being used increasingly often in the clinical setting to treat tendon-related pathologies. Yet the optimal PRP preparations to promote tendon healing in different patient populations are poorly defined. Here, we sought to determine whether increasing the concentration of platelet-derived proteins within a derivative of PRP, platelet lysate (PL), enhances tenocyte proliferation and migration in vitro, and whether the mitogenic properties of PL change with donor age. Methods. Concentrated PLs from both young (< 50 years) and aged (> 50 years) donors were prepared by exposing pooled PRP to a series of freeze-thaw cycles followed by dilution in plasma, and the levels of several platelet-derived proteins were measured using multiplex immunoassay technology. Human tenocytes were cultured with PLs to simulate a clinically relevant PRP treatment range, and cell growth and migration were assessed using DNA quantitation and gap closure assays, respectively. Results. Platelet-derived protein levels increased alongside higher PL concentrations, and PLs from both age groups improved tenocyte proliferation relative to control conditions. However, PLs from aged donors yielded a dose-response relationship in tenocyte behaviour, with higher PL concentrations resulting in increased tenocyte proliferation and migration. Conversely, no significant differences in tenocyte behaviour were detected when increasing the concentration of PLs from younger donors. Conclusion. Higher PL concentrations, when prepared from the PRP of aged but not young donors, were more effective than lower PL concentrations at promoting tenocyte proliferation and migration in vitro. Cite this article: D. R. Berger, C. J. Centeno, N. J. Steinmetz. Platelet lysates from aged donors promote human tenocyte proliferation and migration in a concentration-dependent manner. Bone Joint Res 2019;8:32–40. DOI: 10.1302/2046-3758.81.BJR-2018-0164.R1

Objectives. The ability to determine human bone stiffness is of clinical relevance in many fields, including bone quality assessment and orthopaedic prosthesis design. Stiffness can be measured using compression testing, an experimental technique commonly used to test bone specimens in vitro. This systematic review aims to determine how best to perform compression testing of human bone. Methods. A keyword search of all English language articles up until December 2017 of compression testing of bone was undertaken in Medline, Embase, PubMed, and Scopus databases. Studies using bulk tissue, animal tissue, whole bone, or testing techniques other than compression testing were excluded. Results. A total of 4712 abstracts were retrieved, with 177 papers included in the analysis; 20 studies directly analyzed the compression testing technique to improve the accuracy of testing. Several influencing factors should be considered when testing bone samples in compression. These include the method of data analysis, specimen storage, specimen preparation, testing configuration, and loading protocol. Conclusion. Compression testing is a widely used technique for measuring the stiffness of bone but there is a great deal of inter-study variation in experimental techniques across the literature. Based on best evidence from the literature, suggestions for bone compression testing are made in this review, although further studies are needed to establish standardized bone testing techniques in order to increase the comparability and reliability of bone stiffness studies. Cite this article: S. Zhao, M. Arnold, S. Ma, R. L. Abel, J. P. Cobb, U. Hansen, O. Boughton. Standardizing compression testing for measuring the stiffness of human bone. Bone Joint Res 2018;7:524–538. DOI: 10.1302/2046-3758.78.BJR-2018-0025.R1

Objectives. The purpose of this study was to examine the bactericidal efficacy of hydrogen peroxide (H. 2. O. 2. ) on Cutibacterium acnes (C. acnes). We hypothesize that H. 2. O. 2. reduces the bacterial burden of C. acnes. Methods. The effect of H. 2. O. 2. was assessed by testing bactericidal effect, time course analysis, growth inhibition, and minimum bactericidal concentration. To assess the bactericidal effect, bacteria were treated for 30 minutes with 0%, 1%, 3%, 4%, 6%, 8%, or 10% H. 2. O. 2. in saline or water and compared with 3% topical H. 2. O. 2. solution. For time course analysis, bacteria were treated with water or saline (controls), 3% H. 2. O. 2. in water, 3% H. 2. O. 2. in saline, or 3% topical solution for 5, 10, 15, 20, and 30 minutes. Results were analyzed with a two-way analysis of variance (ANOVA) (p < 0.05). Results. Minimum inhibitory concentration of H. 2. O. 2. after 30 minutes is 1% for H. 2. O. 2. prepared in saline and water. The 3% topical solution was as effective when compared with the 1% H. 2. O. 2. prepared in saline or water. The controls of both saline and water showed no reduction of bacteria. After five minutes of exposure, all mixtures of H. 2. O. 2. reduced the percentage of live bacteria, with the topical solution being most effective (p < 0.0001). Maximum growth inhibition was achieved with topical 3% H. 2. O. 2. . Conclusion. The inexpensive and commercially available topical solution of 3% H. 2. O. 2. demonstrated superior bactericidal effect as observed in the minimum bactericidal inhibitory concentration, time course, and colony-forming unit (CFU) inhibition assays. These results support the use of topical 3% H. 2. O. 2. for five minutes before surgical skin preparation prior to shoulder surgery to achieve eradication of C. acnes for the skin. Cite this article: P. Hernandez, B. Sager, A. Fa, T. Liang, C. Lozano, M. Khazzam. Bactericidal efficacy of hydrogen peroxide on Cutibacterium acnes. Bone Joint Res 2019;8:3–10. DOI: 10.1302/2046-3758.81.BJR-2018-0145.R1

Aims

Several artificial bone grafts have been developed but fail to achieve anticipated osteogenesis due to their insufficient neovascularization capacity and periosteum support. This study aimed to develop a vascularized bone-periosteum construct (VBPC) to provide better angiogenesis and osteogenesis for bone regeneration.

Aims

This study investigated vancomycin-microbubbles (Vm-MBs) and meropenem (Mp)-MBs with ultrasound-targeted microbubble destruction (UTMD) to disrupt biofilms and improve bactericidal efficiency, providing a new and promising strategy for the treatment of device-related infections (DRIs).

Aims

In this investigation, we administered oxidative stress to nucleus pulposus cells (NPCs), recognized DNA-damage-inducible transcript 4 (DDIT4) as a component in intervertebral disc degeneration (IVDD), and devised a hydrogel capable of conveying small interfering RNA (siRNA) to IVDD.

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The metabolic variations between the cartilage of osteoarthritis (OA) and Kashin-Beck disease (KBD) remain largely unknown. Our study aimed to address this by conducting a comparative analysis of the metabolic profiles present in the cartilage of KBD and OA.

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The efficacy of saline irrigation for treatment of implant-associated infections is limited in the presence of porous metallic implants. This study evaluated the therapeutic efficacy of antibiotic doped bioceramic (vancomycin/tobramycin-doped polyvinyl alcohol composite (PVA-VAN/TOB-P)) after saline wash in a mouse infection model implanted with titanium cylinders.

Aims

Rotator cuff muscle atrophy and fatty infiltration affect the clinical outcomes of rotator cuff tear patients. However, there is no effective treatment for fatty infiltration at this time. High-intensity interval training (HIIT) helps to activate beige adipose tissue. The goal of this study was to test the role of HIIT in improving muscle quality in a rotator cuff tear model via the β3 adrenergic receptor (β3AR).

Aims

Research on hip biomechanics has analyzed femoroacetabular contact pressures and forces in distinct hip conditions, with different procedures, and used diverse loading and testing conditions. The aim of this scoping review was to identify and summarize the available evidence in the literature for hip contact pressures and force in cadaver and in vivo studies, and how joint loading, labral status, and femoral and acetabular morphology can affect these biomechanical parameters.

Aims

The incidence of limb fractures in patients living with HIV (PLWH) is increasing. However, due to their immunodeficiency status, the operation and rehabilitation of these patients present unique challenges. Currently, it is urgent to establish a standardized perioperative rehabilitation plan based on the concept of enhanced recovery after surgery (ERAS). This study aimed to validate the effectiveness of ERAS in the perioperative period of PLWH with limb fractures.

Aims

Mesenchymal stem cells (MSCs) are usually cultured in a normoxic atmosphere (21%) in vitro, while the oxygen concentrations in human tissues and organs are 1% to 10% when the cells are transplanted in vivo. However, the impact of hypoxia on MSCs has not been deeply studied, especially its translational application.

Aims

Ultrasound-guided injection techniques are expected to enhance therapeutic efficacy for skeletal muscle injuries and disorders, but basic knowledge is lacking. The purpose of this study was to examine the diagnostic accuracy of ultrasound for abnormal skeletal muscle lesions, and to examine the distribution patterns of solution and cells injected into abnormal muscle lesions under ultrasound guidance.

Aims

Electromagnetic induction heating has demonstrated in vitro antibacterial efficacy over biofilms on metallic biomaterials, although no in vivo studies have been published. Assessment of side effects, including thermal necrosis of adjacent tissue, would determine transferability into clinical practice. Our goal was to assess bone necrosis and antibacterial efficacy of induction heating on biofilm-infected implants in an in vivo setting.

Aims

Fracture-related infection (FRI) is commonly classified based on the time of onset of symptoms. Early infections (< two weeks) are treated with debridement, antibiotics, and implant retention (DAIR). For late infections (> ten weeks), guidelines recommend implant removal due to tolerant biofilms. For delayed infections (two to ten weeks), recommendations are unclear. In this study we compared infection clearance and bone healing in early and delayed FRI treated with DAIR in a rabbit model.

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To investigate the efficacy of ethylenediaminetetraacetic acid-normal saline (EDTA-NS) in dispersing biofilms and reducing bacterial infections.

Aims

Rheumatoid arthritis (RA) is a common chronic immune disease. Berberine, as its main active ingredient, was also contained in a variety of medicinal plants such as Berberaceae, Buttercup, and Rutaceae, which are widely used in digestive system diseases in traditional Chinese medicine with anti-inflammatory and antibacterial effects. The aims of this article were to explore the therapeutic effect and mechanism of berberine on rheumatoid arthritis.

Aims

The presence of facet tropism has been correlated with an elevated susceptibility to lumbar disc pathology. Our objective was to evaluate the impact of facet tropism on chronic lumbosacral discogenic pain through the analysis of clinical data and finite element modelling (FEM).

Aims

Biofilm infections are among the most challenging complications in orthopaedics, as bacteria within the biofilms are protected from the host immune system and many antibiotics. Halicin exhibits broad-spectrum activity against many planktonic bacteria, and previous studies have demonstrated that halicin is also effective against Staphylococcus aureus biofilms grown on polystyrene or polypropylene substrates. However, the effectiveness of many antibiotics can be substantially altered depending on which orthopaedically relevant substrates the biofilms grow. This study, therefore, evaluated the activity of halicin against less mature and more mature S. aureus biofilms grown on titanium alloy, cobalt-chrome, ultra-high molecular weight polyethylene (UHMWPE), devitalized muscle, or devitalized bone.

Aims

The goal was to evaluate tibiofemoral knee joint kinematics during stair descent, by simulating the full stair descent motion in vitro. The knee joint kinematics were evaluated for two types of knee implants: bi-cruciate retaining and bi-cruciate stabilized. It was hypothesized that the bi-cruciate retaining implant better approximates native kinematics.

Aims

The management of periprosthetic joint infection (PJI) remains a major challenge in orthopaedic surgery. In this study, we aimed to characterize the local bone microstructure and metabolism in a clinical cohort of patients with chronic PJI.

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To explore the clinical efficacy of using two different types of articulating spacers in two-stage revision for chronic knee periprosthetic joint infection (kPJI).

Aims

Transcription factor nuclear factor kappa B (NF-κB) plays a major role in the pathogenesis of chronic inflammatory diseases in all organ systems. Despite its importance, NF-κB targeted drug therapy to mitigate chronic inflammation has had limited success in preclinical studies. We hypothesized that sex differences affect the response to NF-κB treatment during chronic inflammation in bone. This study investigated the therapeutic effects of NF-κB decoy oligodeoxynucleotides (ODN) during chronic inflammation in male and female mice.

Aims

A substantial fraction of patients undergoing knee arthroplasty (KA) or hip arthroplasty (HA) do not achieve an improvement as high as the minimal clinically important difference (MCID), i.e. do not achieve a meaningful improvement. Using three patient-reported outcome measures (PROMs), our aim was: 1) to assess machine learning (ML), the simple pre-surgery PROM score, and logistic-regression (LR)-derived performance in their prediction of whether patients undergoing HA or KA achieve an improvement as high or higher than a calculated MCID; and 2) to test whether ML is able to outperform LR or pre-surgery PROM scores in predictive performance.

Aims

This study aimed to investigate the role and mechanism of meniscal cell lysate (MCL) in fibroblast-like synoviocytes (FLSs) and osteoarthritis (OA).

Aims

This study was designed to characterize the recurrence incidence and risk factors of antibiotic-loaded cement spacer (ALCS) for definitive bone defect treatment in limb osteomyelitis.

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In this study, we aimed to visualize the spatial distribution characteristics of femoral head necrosis using a novel measurement method.

Aims

The optimum type of antibiotics and their administration route for treating Gram-negative (GN) periprosthetic joint infection (PJI) remain controversial. This study aimed to determine the GN bacterial species and antibacterial resistance rates related to clinical GN-PJI, and to determine the efficacy and safety of intra-articular (IA) antibiotic injection after one-stage revision in a GN pathogen-induced PJI rat model of total knee arthroplasty.

Aims

Mechanical stimulation is a key factor in the development and healing of tendon-bone insertion. Treadmill training is an important rehabilitation treatment. This study aims to investigate the benefits of treadmill training initiated on postoperative day 7 for tendon-bone insertion healing.

Aims

Pigment epithelium-derived factor (PEDF) is known to induce several types of tissue regeneration by activating tissue-specific stem cells. Here, we investigated the therapeutic potential of PEDF 29-mer peptide in the damaged articular cartilage (AC) in rat osteoarthritis (OA).

Aims

This study explored the shared genetic traits and molecular interactions between postmenopausal osteoporosis (POMP) and sarcopenia, both of which substantially degrade elderly health and quality of life. We hypothesized that these motor system diseases overlap in pathophysiology and regulatory mechanisms.

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Mendelian randomization (MR) is considered to overcome the bias of observational studies, but there is no current meta-analysis of MR studies on rheumatoid arthritis (RA). The purpose of this study was to summarize the relationship between potential pathogenic factors and RA risk based on existing MR studies.

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This study aimed to define the histopathology of degenerated humeral head cartilage and synovial inflammation of the glenohumeral joint in patients with omarthrosis (OmA) and cuff tear arthropathy (CTA). Additionally, the potential of immunohistochemical tissue biomarkers in reflecting the degeneration status of humeral head cartilage was evaluated.

Aims

Osteoarthritis (OA) is a common degenerative disease. PA28γ is a member of the 11S proteasome activator and is involved in the regulation of several important cellular processes, including cell proliferation, apoptosis, and inflammation. This study aimed to explore the role of PA28γ in the occurrence and development of OA and its potential mechanism.

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The mechanism by which synovial fluid (SF) kills bacteria has not yet been elucidated, and a better understanding is needed. We sought to analyze the antimicrobial properties of exogenous copper in human SF against Staphylococcus aureus.

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There is a lack of biomaterial-based carriers for the local delivery of rifampicin (RIF), one of the cornerstone second defence antibiotics for bone infections. RIF is also known for causing rapid development of antibiotic resistance when given as monotherapy. This in vitro study evaluated a clinically used biphasic calcium sulphate/hydroxyapatite (CaS/HA) biomaterial as a carrier for dual delivery of RIF with vancomycin (VAN) or gentamicin (GEN).

Aims

Circular RNA (circRNA) is involved in the regulation of articular cartilage degeneration induced by inflammatory factors or oxidative stress. In a previous study, we found that the expression of circStrn3 was significantly reduced in chondrocytes of osteoarthritis (OA) patients and OA mice. Therefore, the aim of this paper was to explore the role and mechanism of circStrn3 in osteoarthritis.

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As has been shown in larger animal models, knee immobilization can lead to arthrofibrotic phenotypes. Our study included 168 C57BL/6J female mice, with 24 serving as controls, and 144 undergoing a knee procedure to induce a contracture without osteoarthritis (OA).

Aims

The involvement of cyclin D1 in the proliferation of microglia, and the generation and maintenance of bone cancer pain (BCP), have not yet been clarified. We investigated the expression of microglia and cyclin D1, and the influences of cyclin D1 on pain threshold.

Aims

The effects of remnant preservation on the anterior cruciate ligament (ACL) and its relationship with the tendon graft remain unclear. We hypothesized that the co-culture of remnant cells and bone marrow stromal cells (BMSCs) decreases apoptosis and enhances the activity of the hamstring tendons and tenocytes, thus aiding ACL reconstruction.

Aims

The purpose of this study was to explore a simple and effective method of preparing human acellular amniotic membrane (HAAM) scaffolds, and explore the effect of HAAM scaffolds with juvenile cartilage fragments (JCFs) on osteochondral defects.

Aims

There is a considerable challenge in treating bone infections and orthopaedic device-associated infection (ODAI), partly due to impaired penetration of systemically administrated antibiotics at the site of infection. This may be circumvented by local drug administration. Knowledge of the release kinetics from any carrier material is essential for proper application. Ceftriaxone shows a particular constant release from calcium sulphate (CaSO₄) in vitro, and is particularly effective against streptococci and a large portion of Gram-negative bacteria. We present the clinical release kinetics of ceftriaxone-loaded CaSO₄ applied locally to treat ODAI.

Aims

To test the hypothesis that reseeded anterior cruciate ligament (ACL)-derived cells have a better ability to survive and integrate into tendon extracellular matrix (ECM) and accelerate the ligamentization process, compared to adipose-derived mesenchymal stem cells (ADMSCs).

Objectives. Infection of implants is a major problem in elective and trauma surgery. Heating is an effective way to reduce the bacterial load in food preparation, and studies on hyperthermia treatment for cancer have shown that it is possible to heat metal objects with pulsed electromagnetic fields selectively (PEMF), also known as induction heating. We therefore set out to answer the following research question: is non-contact induction heating of metallic implants effective in reducing bacterial load in vitro?. Methods. Titanium alloy cylinders (Ti6Al4V) were exposed to PEMF from an induction heater with maximum 2000 watts at 27 kHz after being contaminated with five different types of micro-organisms: Staphylococcus epidermidis; Staphylococcus aureus; Pseudomonas aeruginosa; spore-forming Bacillus cereus; and yeast Candida albicans. The cylinders were exposed to incremental target temperatures (35°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C) for up to 3.5 minutes. Results. There was an average linear heating rate of 0.39°C per second up to the target temperature, and thereafter the target temperature was maintained until the end of the experiment. At 60°C and higher (duration 3.5 minutes), there was a 6-log reduction or higher for every micro-organism tested. At 60°C, we found that the shortest duration of effective induction heating was 1.5 minutes. This resulted in a 5-log reduction or higher for every micro-organism tested. Conclusion. Non-contact induction heating of a titanium disk is effective in reducing bacterial load in vitro. These promising results can be further explored as a new treatment modality for infections of metal orthopaedic implants. Cite this article: B. G. Pijls, I. M. J. G. Sanders, E. J. Kuijper, R. G. H. H. Nelissen. Non-contact electromagnetic induction heating for eradicating bacteria and yeasts on biomaterials and possible relevance to orthopaedic implant infections: In vitro findings. Bone Joint Res 2017;6:323–330. DOI: 10.1302/2046-3758.65.BJR-2016-0308.R1

Aims

To verify whether secretory leucocyte protease inhibitor (SLPI) can promote early tendon-to-bone healing after anterior cruciate ligament (ACL) reconstruction.