Objectives. During open orthopaedic surgery, joints may be exposed to air, potentially leading to cartilage
Design of bone tissue engineering scaffolds imposes a number of requirements for their physical properties, in particular porosity and mechanical behaviour. Alginates are known as a potential material for such purposes, usually deploying calcium as a cross-linker. Calcium over-expression was reported having proinflammatory effect, which is not always desirable. Contrary to this, barium has better immunomodulatory outcome but data for barium as a cross-linker are scarce. In this work the objective was to produce Ba-linked alginates and compare their viscoelastic properties with Ca-linked controls in vitro. Sodium alginate aqueous solution (1 wt%) with 0.03 wt.% CaCl. 2. is gelled in dialysis tubing immersed in 27 mM CaCl. 2. (controls) or BaCl. 2. , for 48 h, followed by freeze-drying and rehydration (with 0.3 wt.% CaCl. 2. and 0.8 wt.% NaCl). Hydrogel discs (diameter 8-10 mm, thickness 4-6 mm) were assessed in
Introduction. Histology is still considered the gold standard method for the evaluation of soft tissues in the musculoskeletal field, thanks to the possibility of studying structures using different staining and high magnification microscopy. To overcome the intrinsic limits of this method, contrast enhanced microtomographic (CE- microCT) protocols are constantly evolving to allow 3D study of soft tissues. However, no standardized approaches are available, and many concerns exist about the alterations induced to the samples. Method. microCT/histology protocols were explored on human tendons and menisci. To enhance contrast tissues for microCT scanning 1) examethyldisilazane
Abstract. Objective. In this systematic review we aim to compare wound complication rates from Negative Pressure Wound Therapy (NPWT) to
The aim of this study is to print 3D polycaprolactone (PCL) scaffolds at high and low temperature (HT/LT) combined with salt leaching to induced porosity/larger pore size and improve material degradation without compromising cellular activity of printed scaffolds. PCL solutions with sodium chloride (NaCl) particles either directly printed in LT or were casted,
The purpose of this study is to enhance massive bone allografts osseointegration used to reconstruct large bone defects. These allografts show >50% complication rate requiring surgical revision in 20% cases. A new protocol for total bone decellularisation exploiting the vasculature can offer a reduction of postoperative complication by annihilating immune response and improving cellular colonization/ osseointegration. The nutrient artery of 18 porcine bones - humerus/femur/radius/ulna - was cannulated. The decellularization process involved immersion and sequential perfusion with specific solvents over a course of one week. Perfusion was realized by a peristaltic pump (mean flow rate: 6ml/min). The benefit of arterial perfusion was compared to a control group kept in immersion baths without perfusion. Bone samples were processed for histology (HE, Masson's trichrome and DAPI for cell detection), immunohistochemistry (IHC : Collagen IV/elastin for intraosseous vascular system evaluation, Swine Leukocyte Antigen – SLA for immunogenicity in addition to cellular clearance) and DNA quantification. Sterility and solvent residues in the graft were also evaluated with thioglycolate test and pH test respectively. Compared to native bones, no cells could be detected and residual DNA was <50ng/mg
Introduction. In tissue engineering, the establishment of sufficient vascularization is essential for tissue viability and functionality. Inadequate vascularization disrupts nutrients and oxygen supply. Nonetheless, regenerating intricate vascular networks represents a significant challenge. Consequently, research efforts devoted to preserving and regenerating functional vascular networks in engineered tissues are of paramount importance. The present work aims to validate a decellularisation process with preservation of the vascular network and extracellular matrix (ECM) components in fasciocutaneous flaps. Method. Five vascularized fasciocutaneous flaps from cadaveric donors were carefully harvested from the anterolateral thigh (ALT), preserving the main perforator of the fascia lata. The entire ALT flap underwent decellularization by perfusion using a clinically validated chemical protocol. Fluoroscopy and computed tomography (CT) were used to analyze the persistence of the vascular network within the flap, pre- and post-decellularization. Histological analysis, including hematoxylin and eosin staining, and quantitative DNA assessment evaluated decellularization efficacy. Further qualitative (immunohistochemistry, IHC) and quantitative analyses were conducted to assess the preservation of ECM components, such as collagen, glycosaminoglycans, and elastin. Result. On average, the ALT flap maintains 82% of the perfusion area (p = 0.094) post-treatment. Histological analysis confirmed decellularization efficacy and revealed structural rearrangement. Paired analysis revealed a significant decrease in DNA levels (<14.8 ng/mg of
Osteosarcoma and other types of bone cancers often require bone resection, and backfill with cement. A novel silorane-based cement without PMMA's drawbacks, previously developed for dental applications, has been reformulated for orthopedic use. The aim of this study is to assess each cement's ability to elute doxorubicin, maintain its potency, and maintain suitable weight-bearing strength. The silorane-based epoxy cement was synthesized using a platinum-based Lamoreaux's catalyst. Four groups of cement were prepared. Two PMMA groups, one without any additives, one with 200 mg of doxorubicin. Two silorane groups: one without any additive, one with doxorubicin, added so that the w% of drug into both cements were equal. Pellets 6 × 12 mm were used for testing (ASTM F451). n=10. Ten pellets from each group were kept
According to the latest report from the German Arthroplasty Registry, aseptic loosening is the primary cause of implant failure following primary hip arthroplasty. Osteolysis of the proximal femur due to the stress-shielding of the bone by the implant causes loss of fixation of the proximal femoral stem, while the distal stem remains fixed. Removing a fixed stem is a challenging process. Current removal methods rely on manual tools such as chisels, burrs, osteotomes, drills and mills, which pose the risk of bone fracture and cortical perforation. Others such as ultrasound and laser, generate temperatures that could cause thermal injury to the surrounding tissues and bone. It is crucial to develop techniques that preserve the host bone, as its quality after implant removal affects the outcome of a revision surgery. A gentler removal method based on the transcutaneous heating of the implant by induction is proposed. By reaching the glass transition temperature (T. G. ) of the periprosthetic cement, the cement is expected to soften, enabling the implant to be gently pulled out. The in-vivo environment comprises body fluids and elevated temperatures, which deteriorate the inherent mechanical properties of bone cement, including its T. G. We aimed to investigate the effect of fluid absorption on the T. G. (ASTM E2716-09) and Vicat softening temperature (VST) (ISO 306) of Palacos R cement (Heraeus Medical GmbH) when
Bone is a dynamic tissue that undergoes continuous mechanical forces. Mechanical stimuli applied on scaffolds resembling a part of the human bone tissue affects the osteogenesis [1]. Poly(3,4-ethylenedioxythiophene) (PEDOT) is a piezoelectric material that responds to mechanical stimulation producing an electrical signal, which in turn promotes the osteogenic differentiation of bone-forming cells by opening voltage-gated calcium channels [2]. In this study we examined the biological behavior of pre-osteoblastic cells seeded onto lyophilized piezoelectric PEDOT-containing scaffolds applying uniaxial compression. Two different concentrations of PEDOT (0.10 and 0.15% w/v) were combined with a 5% w/v poly(vinyl alcohol) (PVA) and 5% w/v gelatin, casted into wells, freeze
Introduction. The incidences of fragility fractures, often because of osteoporosis, are increasing. Research has moved towards bioresorbable scaffolds that provide temporary mechanical stability and promote osteogenesis. This research aims to fabricate a 3D printed composite Poly (l-lactic-co-glycolic acid)-strontium doped tricalcium phosphate (PLGA-SrTCP) scaffold and evaluate in an in vitro co culture study containing osteoporotic donor cells. Method. PLGA, PLGA TCP, and PLGA SrTCP scaffolds were produced using Fused Filament Fabrication (FFF). A four-group 35-day cell culture study was carried out using human bone marrow derived mesenchymal stem cells (hMSCs) from osteoporotic and control donors (monoculture) and hMSCs & human monocytes (hMCs) (Co culture). Outcome measures were biochemical assays, PCR, and cell imaging. Cells were cultured on scaffolds that had been pre-degraded for six weeks at 47°C prior to
Current strategy for orthopedic tissue engineering mainly focusses on the regeneration of the damaged tissue using cell-seeded three-dimensional scaffolds. Biocompatible scaffolds with controllable degradation and suitable mechanical property are required to support new tissue in-growth and regeneration . [1]. Porous composite scaffolds made from organic and inorganic materials are highly preferred, which can mimic the natural bone in their composition as well can enhance tissue repair . [2]. Scaffolds with optimum mechanical strength in both
Saline (0.9%) is typically used to rinse joints during osteo-articular surgery. It is not unusual for cartilage to then be exposed to the air of the operating theatre for 1-2hrs, which can lead to chondrocyte death. We have compared the survival of in situ chondrocytes within bovine cartilage which has been rinsed in various solutions or simply drained of synovial fluid (SF) and then allowed to
Summary. Our study shows that a tendon rupture can be successfully augmented with Demineralised Cortical Bone (DCB) giving initial appropriate mechanical strength suitable for in vivo use providing the biological reactions to the graft are favourable. Introduction. Treatment of tendon and ligament injuries remains challenging; the aim is to find a biocompatible substance with mechanical and structural properties that replicate those of normal tendon and ligament. Because of its structural and mechanical properties, we proposed that DCB can be used in repair of tendon and ligament as well as regeneration of the enthesis. DCB is porous, biocompatible and has the potential to be remodelled by the host tissues. 2 studies were designed; in the first we examined the mechanical properties of DCB after gamma irradiation (GI) and freeze
Abstract. Introduction. Bone grafts are utilised in a range of surgical procedures, from joint replacements to treatment of bone loss resulting from cancer. Decellularised allograft bone is a regenerative, biocompatible and immunologically safe potential source of transplant bone. Objectives. To compare the structural and biomechanical parameters of decellularised and unprocessed (cellular) trabecular bone from the human femoral head (FH) and tibial plateau (TP). Methods. Bone pins were harvested from 10 FHs and 11 TPs (27, 34 respectively). Pins were decellularised (0.1% w/v sodium dodecyl sulphate) or retained as cellular controls. QA testing was carried out to assess protocol efficacy (total DNA and histological analysis). Cellular and decellularised FH (n=7) and TP (n=10) were uCT scanned. Material density (MD); apparent density (BV/TV); trabecular connectivity; trabecular number; trabecular thickness (Tb-t) and trabecular spacing were measured. Pins were then compression tested to determine ultimate compressive stress (UCS), Young's modulus and 0.2% proof stress. Results. Total DNA levels of decellularised bone were below 50 ng.mg. −1.
Introduction and Objective. Knee osteoarthritis (KOA) is a frequent disease for which therapeutic possibilities are limited. In current recommendations, the first-line analgesic is acetaminophen. However, low efficacy of acetaminophen, frequently leads to the use of weak opioids (WO) despite their poor tolerance, especially in elderly patients. The primary objective was to compare the analgesic efficacy and safety of a new wearable transcutaneous electrical nerve stimulation (W-TENS) to weak opioids (WO) in the treatment of moderate to severe, nociceptive, chronic pain in knee osteoarthritis patients. Materials and Methods. ArthroTENS study is a phase 3, non-inferiority, multicentric, prospective, randomized, single-blinded for primary efficacy outcome, controlled, in 2-parallel groups, clinical study comparing W-TENS versus WO over a 3-month controlled period with an additional, optional, non-controlled, 3-month follow-up for patients in W-TENS group. The co-primary outcome was KOA pain intensity (PI) at month 3 and the number of adverse events (AEs) over 3 months. Results. The non-inferiority of W-TENS was demonstrated in both the PP and ITT populations. At M3, PI in PP population was 3.87 (2.12) compared to 4.66 (2.37) (delta: −0.79 (0.44); 95% CI (−1.65; 0.08)) in W-TENS and WO groups, respectively. Since the absolute value of the 95% CI of the between-treatments mean PI difference [−1.71, – 0.12] was above 0 in ITT set, the planned superiority analysis was performed, demonstrating that W-TENS was significantly superior to WO at M3 (P=0.0124). At M1 and M3, the W-TENS group reached the absolute minimal clinically important difference (MCID) for an analgesic (1.8 (2.1) and 2.1 (2.3), respectively), corresponding to a 20 mm reduction in PI (interquartile range: 15–30) on a 0–100 mm visual analogic scale – i.e. 2 points on a numerical rating scale – which equates to “much better”. Conversely, in the WO group, a 0.5 (1.8) and a 1.1 (2.1) reduction in PI were observed at M1 and M3, respectively, while a 1-point reduction in PI is required to be considered as a “slightly better” improvement. In WO group, AEs were the common systemic AEs reported with WO (nausea, constipation, drowsiness, dizziness, pruritus, vomiting,
Introduction and Objective. Guided Bone Regeneration (GBR) uses biodegradable collagen membranes of animal origin tissues (dermis and pericardium). Their barrier effect prevents soft tissues to interfere with the regeneration of alveolar bone. However, their xenogeneic origin involves heavy chemical treatments which impact their bioactivity. Wharton's Jelly (WJ) from the umbilical cord is a recoverable surgery waste. WJ is mostly made from collagen fibers, proteoglycans, hyaluronic acid, and growth factors. WJ with immunologically privileged status and bioactive properties lends credence to its use as an allograft. Nevertheless, low mechanical properties limit its use in bone regenerative strategies. Herein, our objective is to develop a crosslinked WJ-based membrane to improve its strength and thus its potential use as a GBR membrane. Materials and Methods. The umbilical cords are collected after delivery and then stored at −20°C until use. The WJ membranes (1 × 5 × 12 mm) were obtained after the removal of blood vessels and amniotic tissue, washed, lyophilized, and stored at −20°C. WJ membranes were incubated in genipin solutions in decreasing concentrations (0.3 g / 100 mL − 0.03 g / 100 mL) for 24 hours at 37°C. The crosslinking degree was estimated by ninhydrin and confirmed by FTIR (Fourier-transform infrared spectroscopy) assays. The swelling rate was obtained after the rehydration of
Abstract. Objectives. Assess and characterise the suitability of a novel silk reinforced biphasic 3D printed scaffold for osteochondral tissue regeneration. Methods. Biphasic hybrid scaffolds consisted of 3D printed poly(ethylene glycol)-terephthalate-poly(butylene terephthalate)(PEGT/PBT) scaffold frame work (pore size 0.75mm), which has been infilled with a cast and freeze
Background:. The Lateral Intercondylar Ridge (LIR) gained notoriety with arthroscopic trans-tibial Anterior Cruciate Ligament (ACL) reconstruction where it was mistakenly used to position the ‘over the top’ guide resulting in graft malposition. With anatomic ACL reconstruction some surgeons use the same ridge to define the anterior margin of the ACL femoral insertion in order to guide graft placement. However there is debate about whether this ridge is a consistent and reliable anatomical structure. The aim of our study was to identify whether the LIR is a consistent anatomical structure and to define its relationship with the femoral ACL insertion. Methods:. In the first part, we studied 23
Collagen is a key component of the extracellular matrix in a variety of tissues and hence is widely used in tissue engineering research, yet collagen has had limited uptake in the field of 3D printing. In this study we successfully adapted an existing electronic printing method, aerosol jet printing (AJP), to print high resolution 3D constructs of recombinant collagen type III (RHCIII). Circular samples with a diameter of 4.5mm and 288 layers thick, or a diameter of 6.5mm and 400 layers thick were printed on glass cover slips with print lines of 60µm. Attenuated Total Reflectance Fourier-Transorm Infa-red (ATR-FTIR) spectroscopy performed on the 4 of the printed samples and