The purpose of this study was to evaluate A total of 60 Sprague-Dawley rats (125 g to 149 g) were implanted
subcutaneously with SWCNT/PLAGA composites (10 mg SWCNT and 1gm
PLAGA 12 mm diameter two-dimensional disks), and at two, four, eight
and 12 weeks post-implantation were compared with control (Sham)
and PLAGA (five rats per group/point in time). Rats were observed
for signs of morbidity, overt toxicity, weight gain and food consumption,
while haematology, urinalysis and histopathology were completed
when the animals were killed.Objectives
Methods
The ability of mesenchymal stem cells (MSCs)
to differentiate Despite their increasing application in clinical trials, the
origin and role of MSCs in the development, repair and regeneration
of organs have remained unclear. Until recently, MSCs could only
be isolated in a process that requires culture in a laboratory;
these cells were being used for tissue engineering without understanding
their native location and function. MSCs isolated in this indirect
way have been used in clinical trials and remain the reference standard
cellular substrate for musculoskeletal engineering. The therapeutic
use of autologous MSCs is currently limited by the need for In this annotation we provide an update on the recent developments
in the understanding of the identity of MSCs within tissues and
outline how this may affect their use in orthopaedic surgery in
the future. Cite this article:
Aim. Aim of this monocentric, prospective study was to evaluate the safety, efficacy, clinical and radiographical results at 24-month follow-up (N = 6 patients) undergoing hip revision surgery with severe acetabular bone defects (Paprosky 2C-3A-3B) using a combination of a novel phase-pure betatricalciumphosphate - collagen 3D matrix with allograft bone chips. Method. Prospective follow-up of 6 consecutive patients, who underwent revision surgery of the acetabular component in presence of massive bone defects between April 2018 and July 2019. Indications for revision included mechanical loosening in 4 cases and history of hip infection in 2 cases. Acetabular deficiencies were evaluated radiographically and CT and classified according to the Paprosky classification. Initial diagnosis of the patients included osteoarthritis (N = 4), a traumatic fracture and a congenital hip dislocation. 5 patients underwent first revision surgery, 1 patient underwent a second revision surgery. Results. All patients were followed-up radiographically with a mean of 25,8 months. No complications were observed direct postoperatively. HHS improved significantly from 23.9 preoperatively to 81.5 at the last follow-up. 5 patients achieved a defined good result, and one patient achieved a fair result. No periprosthetic joint infection, no dislocations, no deep vein thrombosis, no vessel damage, and no complaint about limbs length discrepancy could be observed. Postoperative dysmetria was found to be + 0.2cm (0cm/+1.0cm) compared to the preoperative dysmetria of − 2.4 cm (+0.3cm/−5.7cm). Conclusions. Although used in severe acetabular bone defects, the novel phase-pure betatricalciumphosphate - collagen 3D matrixshowed complete resorption and replacement by newly formed bone, leading to a full implant integration at 24 months follow-up and thus represents a promising method with excellent
Introduction. “Bioexpandable” prostheses after resection of malignant bone tumors in children to lengthen the bone using the method of callus distraction may offer new perspectives and better long-term results. Materials and Methods. The bioexpandable prosthesis is equipped with an encapsulated electromotor which enables the device to perform distraction in an osteotomy gap with about 1mm/day. The new bone is improving the ratio from bone to prosthesis and therewith the potential stability of the final stem. The device is indicated, when limb length discrepancy is getting more than 3 cm or at maturity and can be used in a minimal invasive way for femur lengthening. Results. 11 patients were treated with the bioexpandable prosthesis. The mean age of the patients was 13,5 years and the mean amount of lengthening was 74mm. In 2 cases lengthening was performed in 2 steps and in 1 case in 3 steps. All lengthening procedures could be finished without complications. There was no infection and no technical problem. The
Introduction. Fibrous dysplasia is a pathological condition, where normal medullary bone is replaced by fibrous tissue and small, woven specules of bone. Fibrous dysplasia can occur in epiphysis, metaphysis or diaphysis. Occationally, biopsy is necessary to establish the diagnosis. We present a review of operative treatment using the Ilizarov technique. The management of tibial fibrous dysplasia in children are curettage or subperiosteal resection to extra periosteal wide resection followed by bone transport. Materials and Methods. A total of 18 patients were treated between 2010 – 2020; 12 patients came with pain and 6 with pain and deformity. All patients were treated by Ilizarov technique. Age ranges from 4–14 years. 12 patients by enbloc excision and bone transportation and 6 patients were treated by osteotomy at the true apex of the deformity by introducing the k/wires in the medullary cavity with stable fixation by Ilizarov device. The longest duration for bone transport was 16 weeks (14–20 weeks) for application, after deformity correction was 20 weeks. We have never used any kind of bone grafts. Results. All the 18 patients were treated successfully by Ilizarov compression distraction device. The patients with localized tibial pathology with deformity had the shortest period on the Ilizarov apparatus, 14 weeks. Conclusions. Preservation and
Aim.
Aim. Osteomyelitis is a difficult-to-treat disease with high chronification rates. The surgical amputation of the afflicted limb sometimes remains as the patients’ last resort. Several studies suggest an increase in mitochondrial fission as a possible contributor to the accumulation of intracellular reactive oxygen species and thereby to cell death of infectious bone cells. The aim of this study is to analyze the ultrastructural impact of bacterial infection and its accompanying microenvironmental tissue hypoxia on osteocytic and osteoblastic mitochondria. Method. 19 Human bone tissue samples from patients with osteomyelitis were visualized via light microscopy and transmission electron microscopy. Osteoblasts, osteocytes and their respective mitochondria were histomorphometrically analyzed. The results were compared to the control group of 5 non-infectious human bone tissue samples. Results. The results depicted swollen hydropic mitochondria including depleted cristae and a decrease in matrix density in the infectious samples as a common finding in both cell types. Furthermore, perinuclear clustering of mitochondria could also be observed regularly. Additionally, increases in relative mitochondrial area and number could be found as a sign for increased mitochondrial fission. Conclusions. The results show that mitochondrial morphology is altered during osteomyelitis in a comparable way to mitochondria from hypoxic tissues. This suggests that manipulation of mitochondrial dynamics in a way of inhibiting mitochondrial fission may improve bone cell survival and exploit
Fracture non-union can be as high as 20% in certain clinical scenarios and has a high associated socioeconomic burden. Boron has been shown to regulate the Wnt/β-catenin pathway in other bodily processes. However, this pathway is also critical for bone healing. Here we aim to demonstrate that the local delivery of boric acid can accelerate bone healing, as well as to elucidate how boric acid, via the regulationtheWnt/β-catenin pathway, impacts theosteogenic response of bone-derived osteoclasts and osteoblasts during each phase of bone repair. Bilateral femoral cortical defects were created in 32 skeletally mature C57 mice. On the experimental side, boric acid (8mg/kg concentration) was injected locally at the defect site whereas on the control side, saline was used. Mice were euthanized at 7, 14, and 28 days. MicroCT was used to quantify
A novel injectable hydrogel based on DNA and silicate nanodisks was fabricated and optimized to obtain a suitable drug delivery platform for biomedical applications. Precisely, the hydrogel was designed by combining two different type of networks: a first network (type A) made of interconnections between neighboring DNA strands and a second one (type B) consisting of electrostatic interactions between the silicate nanodisks and the DNA backbone. The silicate nanodisks were introduced to increase the viscosity of the DNA physical hydrogel and improve their shear-thinning properties. Additionally, the silicate nanodisks were selected to modulate the release capability of the designed network. DNA 4% solutions were heated at 90°C for 45 seconds and cooled down at 37°C degree for two hours. In the second step, the silicate nanodisks suspension in water at different concentrations (0.1 up to 0.5%) were then mixed with the pre-gel DNA hydrogels to obtain the nanocomposite hydrogels. Rheological studies were carried out to investigate the shear thinning properties of the hydrogels. Additionally, the hydrogels were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron microscopy. The hydrogels were loaded with the osteoinductive drug dexamethasone and its release was tested in vitro in phosphate buffer pH 7.4. The drug activity upon release was tested evaluating the osteogenic differentiation of human adipose derived stem cells (hASCs) in vitro through analysis of main osteogenic markers and quantification of alkaline phosphatase activity and calcium deposition. Finally, the hydrogels were tested in vivo and injected into cranial defects in rats to assess their biocompatibility and
Previously, we reported impaired biomechanical bone properties and inferior bone matrix quality in tachykinin1 (Tac1)-deficient mice lacking the sensory neuropeptide substance P (SP). Additionally, fracture callus development is affected by the absence of SP indicating a critical effect of sensory nerve fibers on bone health and regeneration. For α-calcitonin gene-related peptide (α-CGRP)-deficient mice, a profound distortion of bone microarchitecture has also been described. We hypothesize that SP and α-CGRP modulate inflammatory as well as pain-related processes and positively affect
Distraction osteogenesis with intramedullary lengthening devices has undergone rapid development in the past decade with implant enhancement. In this first single-centre matched-pair analysis we focus on the comparison of treatment with the PRECICE and STRYDE intramedullary lengthening devices and aim to clarify any clinical and radiological differences. A single-centre 2:1 matched-pair retrospective analysis of 42 patients treated with the STRYDE and 82 patients treated with the PRECICE nail between May 2013 and November 2020 was conducted. Clinical and lengthening parameters were compared while focusing radiological assessment on osseous alterations related to the nail’s telescopic junction and locking bolts at four different stages.Aims
Methods
We present the results of a new non-invasive lengthening nail enabling accurate control of the lengthening process and joint rehabilitation. Introduction. The use of intramedullary lengthening nails have gained popularity as they reduce common complications associated with external fixators, including infection, joint stiffness,
We present our experience of lower limb reconstruction for patients with obvious defects in the tibia, by bone transport using a stacked Taylor Spatial Frame. A retrospective review of 40 patients treated between 2003 and 2009. There were 19 cases of infected non union, 9 cases of acute bone loss following fracture, 6 cases of chronic osteomyelitis, 4 cases of aseptic non union, 1 case of neurofibromatosis and 1 case of a loose and infected total ankle replacement. Twenty-eight out of the 40 patients reviewed have completed their treatment. Of these 28 patients, bony union was achieved in 23 patients, of whom 22 were assessed at discharge to have regained good to excellent limb function, a functional assessment was not available for review in the remaining patient. In 5 patients, docking site union failed, 3 of whom then underwent below knee amputation. Two patients required treatment with an intramedullary nail following frame treatment to achieve consolidated union of the docking site. Anatomic sagittal and coronal alignment was achieved in 19 out of 23 patients. The mean
Introduction. We present our experience of lower limb reconstruction for patients with obvious defects in the tibia, by bone transport using a stacked Taylor Spatial Frame. Methods. A retrospective review of 40 patients treated between 2003 and 2009. There were 19 cases of infected non union, 9 cases of acute bone loss following fracture, 6 cases of chronic osteomyelitis, 4 cases of aseptic non union, 1 case of neurofibromatosis and 1 case of a loose and infected total ankle replacement. Results. 28 out of the 40 patients reviewed have completed their treatment. Of these 28 patients, bony union was achieved in 23 patients, of whom 22 were assessed at discharge to have regained good to excellent limb function; a functional assessment was not available for review in the remaining patient. In 5 patients docking site union failed, 3 of whom then underwent below-knee amputation. Two patients required treatment with an intramedullary nail following frame treatment to achieve consolidated union of the docking site. Anatomic sagittal and coronal alignment was achieved in 19 out of 23 patients. The mean
Periosteum is important for bone homoeostasis
through the release of bone morphogenetic proteins (BMPs) and their
effect on osteoprogenitor cells. Smoking has an adverse effect on
fracture healing and
In revision surgery of a neglected loose cemented stem, especially if long-standing infection is present, the bone may become extremely thin and fragile. A fracture during implant removal, therefore, occurs readily and the bone may simply disintegrate so that it cannot be reconstructed to produce intrinsic stability. In such cases, rather than try to put together a house of cards, the bail and nail technique may be used. I first described this in 1992. A large bore intramedullary nail is inserted into what is left of the femur and the bone fragments proximally or cerclage wires are around the nail. The patient is left with a Girdlestone. Most patients cannot weight-bear on a Girdlestone for about two months. After that time, they are encouraged to do so as load bearing speeds healing and
The physiological effects of 1,25 vitamin D3 (1,25D) are well known and the previously held dogma was that this was the only active vitamin D metabolite. A number of methods have been employed to demonstrate the effects of 24,25-dihydroxyvitamin D3 (24,25D) on osteoblast maturation responses, in the presence of FHBP, ((3S) 1-Fluoro-3-hydroxy-4-(oleoyloxy)butyl-1-phosphonate), an agonist of lysophosphatidic acid (LPA). These include alkaline phosphatase (ALP) expression and investigation of the role of CYP27B1, which is the enzyme responsible for converting 24,25D to 1,24,25D. Ketoconazole, which inhibits the actions of CYP27B1, as well as an enzyme-linked immunosorbant assay (ELISA) for CYP27B1 were used. The results clearly demonstrate that 24,25D stimulates maturation of MG63 cells when combined with FHBP. It has also been shown that the metabolite is not converted to another active form (for example, 1,24,25D) within osteoblasts, due to the absence of CYP27B1. 24,25D is an active vitamin D metabolite and exerts its effects in a bone fide manner, rather than following conversion to another active metabolite in osteoblasts. Given it is non-calcaemic, this metabolite has the exciting potential of being used in a
Aim. The demand for a synthetic bone substitute that can build bone and at the same time kill bacteria is high. The aim of this study was to compare the elution of gentamicin from a new synthetic bone substitute in vitro with the performance in clinical applications. Method. Gentamicin release was measured from a synthetic bone graft substitute, comparing in vitro and clinical conditions:. 1). elution in Ringers solution. The bone graft substitute contained 175mg gentamicin per 10mL. The material was introduced either as paste or as pre-set beads with a high or low surface areas, >100cm. 2. and 24cm. 2. respectively. The gentamycin release was measured by daily collection of samples. 2). elution in patients treated for trochanteric hip fractures(n=6) or uncemented hip revisions(n=5) 7,3±1,1mL of substitute was implanted and drainage was collected at 6h,12h,24h,30h,36h post-op. Blood serum was collected every hour for the first 6h and thereafter every 6h until 4 days post-op, urine – daily for the first 7 days post-op. 3). elution in patients treated after bone tumor resection(n=8), 12,1±5,5mL of substitute was implanted and both drainage and blood serum were collected daily until 2 days post-op. Gentamicin concentrations were analyzed using antibody technique. Results. In the in vitro study, there was an initial peak in the gentamicin concentration (GC) for all the samples and at a level above 4mg/L, which is the MIC break point, during the whole test period of 28 days. All gentamicin was released during the test period and more than 95 % had been released after 2–4 days independently of the surface area of the material, or if it was pre-set or paste. In the clinical studies similar results were found. Gentamicin was detected in the drainage until 2 days post-op. and the hip patients 40% less GC – compared to the tumor patients. In the blood serum with higher GC in the tumor patients and non-detectable levels after 2 days post-op for the hip patients. The GC was significantly lower than maximum systemic level recommended of 12 mg/L. In the urine, GC was above the MIC of 4mg/L for the first seven days post-op. Conclusions. A reliable in vitro test method has been identified for the future development of additional new and effective antibiotic containing bone substitutes. The new
Gene-activated scaffolds have shown potential in localised gene delivery resulting in bone tissue regeneration. In this study, the ability of two gene delivery vectors, polyethyleneimine (PEI) and nano-hydroxyapatite (nHA), to act as carriers for the delivery of therapeutic genes when combined with our collagen-nHA (coll-nHA) scaffolds to produce gene-activated scaffolds [1, 2], was determined. In addition, coll-nHA-dual gene scaffolds containing both an angiogenic gene and an osteogenic gene were assessed for bone healing in an in vivo Wistar rat calvarial defect model. When cells were applied to the coll-nHA scaffolds under osteogenic conditions in vitro, the dual scaffolds exhibited significantly superior osteogenic potential when analysed using microCT, calcium quantification and histology compared to single-gene scaffolds and gene-free controls. When the dual scaffolds were assessed in vivo, the nHA dual scaffold outperformed all other groups as early as 4 weeks post-implantation as determined using X-ray, microCT, quantification of new bone volume, histology and vessel formation. This research has demonstrated the potential of using novel coll-nHA scaffolds for therapeutic gene therapy while also being capable of simultaneously delivering numerous genes. This study underlines the effect of specifically tailoring gene-activated scaffolds for
