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The Bone & Joint Journal
Vol. 105-B, Issue 1 | Pages 88 - 96
1 Jan 2023
Vogt B Rupp C Gosheger G Eveslage M Laufer A Toporowski G Roedl R Frommer A

Aims

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.

Methods

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.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_15 | Pages 5 - 5
1 Dec 2021
Alagboso F Mannala G Steinmann S Docheva D Rupp M Brochhausen C Alt V
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Aim. Bone regeneration following the treatment of Staphylococcal bone infection or osteomyelitis is challenging due to the ability of Staphylococcus aureus to invade and persist within bone cells, which could possibly lead to antimicrobial tolerance and incessant bone destruction. Here, we investigated the influence of Staphylococcal bone infection on osteoblasts metabolism and function, with the underlying goal of determining whether Staphylococcus aureus-infected osteoblasts retain their ability to produce extracellular mineralized organic matrix after antibiotic treatment. Method. Using our in vitro infection model, human osteoblasts-like Saos-2 cells were infected with high-grade Staphylococcus aureus EDCC 5055 strain, and then treated with 8 µg/ml rifampicin and osteogenic stimulators up to 21-days. Results. Immunofluorescence and transmission electron microscopic (TEM) imaging demonstrated the presence of intracellular bacteria within the infected osteoblasts as early as 2 hours post-infection. TEM micrographs revealed intact intracellular bacteria with dividing septa indicative of active replication. The infected osteoblasts showed significant amounts of intracellular bacteria colonies and alteration in metabolic activity compared to the uninfected osteoblasts (p≤0.001). Treatment of S. aureus-infected osteoblasts with a single dose of 8 µg/ml rifampicin sufficiently restored the metabolic activity comparative to the uninfected groups. Alizarin red staining and quantification of the rifampicin-treated infected osteoblasts revealed significantly lower amount of mineralized extracellular matrix after 7-days osteogenesis (p<0.05). Interestingly, prolonged osteogenic stimulation and rifampicin-treatment up to 21 days improved the extracellular matrix mineralization level comparable to the rifampicin-treated uninfected group. However, the untreated (native) osteoblasts showed significantly more quantity of mineral deposits (p≤0.001). Ultrastructural analysis of the rifampicin-treated infected osteoblasts at 21-days osteogenesis revealed active osteoblasts and newly differentiated osteocytes, with densely distributed calcium crystal deposits within the extracellular organic matrix. Moreover, residual colony of dead bacteria bodies and empty vacuoles of the fully degraded bacteria embedded within the mineralized extracellular matrix. Gene expression level of prominent bone formation markers, namely RUNX2, COL1A1, ALPL, BMP-2, SPARC, BGLAP, OPG/RANKL showed no significant difference between the infected and uninfected osteoblast at 21-days of osteogenesis. Conclusions. Staphylococcus aureus bone infection can drastically impair osteoblasts metabolism and function. However, treatment with potent intracellular penetrating antibiotics, namely rifampicin restored the metabolic and bone formation activity of surviving osteoblasts. Delay in early osteogenesis caused by the bacterial infection was significantly improved over time after successful intracellular bacteria eradication


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_15 | Pages 46 - 46
7 Nov 2023
Moosa S
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Medical Genetics is a transversal discipline with the potential to impact on every specialty and subspecialty in medicine and the allied health sciences. The completion of the human genome project resulted in technical advancements in genomics, genomic testing and our understanding of genetic disorders in general. These advancements have greatly enhanced our understanding of the role of genetics in Orthopaedic practice, with respect to both monogenic and complex disorders. Tygerberg Hospital is currently the only state hospital in South Africa to support genetic testing in the form of gene panels as part of routine care. This is complemented by more comprehensive research testing in the form of exome and genome sequencing as part of the Undiagnosed Disease Programme. We audit the genetic and genomic testing done on patients referred from the Orthopaedic clinic over a period of 3 years (2020–2022) and review diagnostic rates and interesting results. The largest group of patients referred (n=50) had a clinical diagnosis of osteogenesis imperfecta (OI). A 100% diagnostic yield was achieved for these patients with the identification of recurring variants (FKBP10, COL1A2). Further families (n=20) with much rarer conditions are presented with important implications on the orthopaedic and medical management, prognosis, and genetic counselling for the families. We highlight the impact of genomic testing in the Orthopaedic clinic. Management changes and precision orthopaedic intervention were only possible due to a genetic diagnosis. We motivate for increased access to testing, especially for younger patients presenting with complex orthopaedic phenotypes


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_15 | Pages 45 - 45
7 Nov 2023
Mwelase S Maré P Marais L Thompson D
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Children with osteogenesis imperfecta (OI) frequently present with coxa vara (CV). Skeletal fragility, severe deformity and limited fixation options make this a challenging condition to correct surgically. Our study aimed to determine the efficacy of the Fassier technique to correct CV and determine the complication rate. Retrospective, descriptive case series from a tertiary hospital. We retrospectively reviewed records of a cohort of eight children (four females, 12 hips) with OI (6/8 Sillence type III, 2/8 type IV) who had surgical treatment with Fassier technique for CV between 2014 and 2020. Inclusion Criteria: All patients with CV secondary to OI treated surgically with Fassier technique. Exclusion Criteria: Patients older than 18 years; Patients with CV treated non-operatively or by surgical technique different to Fassier technique. Data relating to the following parameters was collected and analyzed: demographic data, pre- and postoperative neck shaft angle (NSA), complications and NSA at final follow-up. The mean age at operation was 5.8 years (range 2–10). The mean NSA was corrected from 96.8° preoperatively to 137º postoperatively. At a mean follow-up of 38.6 months, the mean NSA was maintained at 133°, and 83% (10/12) of hips had an NSA that remained greater than 120°. There was a 42% (5/12) complication rate: three Fassier–Duval rods failed to expand after distal epiphyseal fixation was lost during growth; one Rush rod migrated through the lateral proximal femur cortex with recurrent coxa vara; and one Rush rod migrated proximally and required rod revision. The Fassier technique effectively corrected CV in children with moderate and progressively deforming OI. The deformity correction was maintained in the short term. The complication rate was high, but mainly related to the failed expansion of the Fassier–Duval rods


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_17 | Pages 50 - 50
24 Nov 2023
Hotchen A Tsang SJ Dudareva M Sukpanichy S Corrigan R Ferguson J Stubbs D McNally M
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Aim. Patient quality of life (QoL) in untreated bone infection was compared to other chronic conditions and stratified by disease severity. Method. Patients referred for treatment of osteomyelitis (including fracture related infection) were identified prospectively between 2019 and 2023. Patients with confirmed infection completed the EuroQol EQ-5D-5L questionnaire. Clinicians blinded to EQ-index score, grouped patients according to JS-BACH Classification into ‘Uncomplicated’, ‘Complex’ or ‘Limited treatment options’. A systematic review of the literature was performed of other conditions that have been stratified using EQ-index score. Results. 257 patients were referred, and 219 had suspected osteomyelitis. 196 patients had long bone infection and reported an average EQ-index score of 0.455 (SD 0.343). 23 patients with pelvic osteomyelitis had an average EQ-index score of 0.098 (SD 0.308). Compared to other chronic conditions, patients with long-bone osteomyelitis had worse QoL when compared to different types of malignancy (including bladder, oropharyngeal, colorectal, thyroid and myeloma), cardiorespiratory disease (including asthma, COPD and ischaemic heart disease), psychiatric conditions (including depression, pain and anxiety), endocrine disorders (including diabetes mellitus), neurological conditions (including Parkinson's disease, chronic pain and radiculopathy) and musculoskeletal conditions (including osteogenesis imperfecta, fibrous dysplasia and x-linked hypophosphataemic rickets). QoL in long-bone infection was similar to conditions such as Prada-Willi syndrome, Crohn's disease and juvenile idiopathic arthritis. Patients who had a history of stroke or multiple sclerosis reported worse QoL scores compared to long-bone infection. Patients who had pelvic osteomyelitis gave significantly lower QoL scores when compared to all other conditions that were available for comparison in the literature. In long bone infection, 41 cases (21.0%) were classified as ‘Uncomplicated’, 136 (69.4%) as ‘Complex’ and 19 (9.7%) as ‘Limited treatment options available’. Within classification stratification, patients with ‘Uncomplicated’ long bone infections reported a mean EQ-index score of 0.618 (SD 0.227) which was significantly higher compared to ‘Complex’ (EQ-index: 0.410 SD 0.359, p=0.004) and ‘Limited treatment options available’ (EQ-index: 0.400 SD 0.346, p=0.007). Conclusions. Bone and joint infections have a significant impact on patient quality of life. It is much worse when compared to other common chronic conditions, including malignancy, cardiovascular and neurological diseases. This has not been previously reported but may focus attention on the need for more investment in this patient group


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_5 | Pages 35 - 35
1 Apr 2022
See CC Al-Naser S Fernandes J Nicolaou N Giles S
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Introduction. Metabolic bone disease encompasses disorders of bone mineralization, abnormal matrix formation or deposition and alteration in osteoblastic and osteoclastic activity. In the paediatric cohort, patients with metabolic bone disease present with pain, fractures and deformities. The aim was to evaluate the use of lateral entry rigid intramedullary nailing in lower limbs in children and adolescents. Materials and Methods. Retrospective review was performed for an 11-year period. Lower limb rigid intramedullary nailing was performed in 27 patients with a total of 63 segments (57 femora, 6 tibiae). Majority of patients had underlying diagnoses of osteogenesis imperfecta or fibrous dysplasia (including McCune Albright disease). Mean age at surgery was 14 years. Indications for surgery included acute fractures, prophylactic stabilisation, previous nonunion and malunion, deformity correction and lengthening via distraction osteogenesis. Results. All fractures healed. Correction of deformity was successfully achieved in all segments. Delayed union occurred in 4 segments in 1 patient and was successfully treated with nail dynamization. Other complications included prominence, cortical penetrance and loosening of locking screws. One patient who had lengthening performed had nonunion and was managed with exchange nailing and adjunctive measures. Conclusions. Rigid intramedullary nailing is very effective in stabilisation and deformity correction of long bones in adolescent patients with pathological bone disease. The technique has low complication rates. We recommend the use of this technique in paediatric units with experience in managing metabolic bone conditions


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVIII | Pages 4 - 4
1 Sep 2012
Chen C Uludag H Wang Z Jiang H
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Purpose. The data regarding the effects of noggin on bone morphogenetic protein (BMP)-induced osteogenesis of mesenchymal stem cells (MSCs) are controversial. Most studies performed in rodent cells/models indicated that noggin was a negative regulator of BMP-2-induced osteogenesis; however, one study conducted with human MSCs in culture showed that the addition of noggin induced osteogenesis in vitro. To clear the controversy, we designed this study to evaluate the effects of knocking down noggin gene expression on BMP-2-induced osteogenesis of human bone marrow-derived primary MSCs in vitro. Method. MSCs were isolated from human tibial bone marrow by density gradient centrifugation. Two noggin small interfering RNAs (siRNAs) were used in this study to knockdown noggin gene expression. There were four study groups: MSCs with no transfection of siRNA (named as NT group), MSCs transfected with non-targeting negative control siRNA (named as control group), MSCs transfected with noggin siRNA1 (named as NOGsi1 group), and MSCs transfected with noggin siRNA2 (named as NOGsi2 group). After transfection, MSCs were induced to undergo osteogenic differentiation by incubating in basal medium containing 0.1 μg/ml BMP-2 for 35 days. The expression levels of osteoblastic marker genes were measured by real-time quantitative PCR on day 14. Also assessed was alkaline phosphatase (ALP) activity by a colorimetric kinetic assay and Fast Blue B staining on day 14. Calcium deposition was determined by the calcium assay on day 35. Results. The expression levels of integrin binding sialoprotein (IBSP) and osteocalcin (OC) were significantly decreased in both NOGsi1 and NOGsi2 groups compared with NT and control groups (all p<0.038). Although the expression level of runt-related transcription factor 2 (RUNX2) was also reduced in NOGsi1 and NOGsi2 groups compared with NT and control groups, it did not reach statistical significance. ALP activity was significantly lower in NOGsi1 and NOGsi2 groups than that of NT group (both p<0.024). The same pattern was also observed in ALP Fast Blue B staining. Calcium deposition was also significantly decreased in both NOGsi1 and NOGsi2 groups compared with NT group (both p<=0.048). Conclusion. Noggin suppression by siRNA inhibits BMP-2-induced osteogenesis of human bone marrow-derived MSCs. Our results, contrary to the extensive studies conducted in rodent cells/models, corroborated with the previous study that the addition of noggin in the cell culture increased osteogenesis of human MSCs. This suggests that the effects of noggin on BMP-2-induced osteogenesis of MSCs might be species-specific


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_6 | Pages 29 - 29
1 May 2021
Rouse B Giles S Fernandes J
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Introduction. We have previously published limb lengthening using external fixation in pathological bone diseases. We would like to report a case series of femoral lengthening using the PRECICE system in a similar pathological group especially looking at it's feasibility and complications. Materials and Methods. This is a case series of four patients, two patients with osteogenesis imperfecta and two with Ollier's disease, who underwent femoral lengthening via distraction osteogenesis using the PRECICE intramedullary nail system. It was a retrospective study from a prospective database from clinical records and radiographs. Results. The mean age at the time of surgery was 15.5 years, the mean preoperative leg length discrepancy was 30mm, and the mean distraction distance achieved was 28.75mm. Since these patients were of shorter heigh, limb lengthening was considered. All 4 patients had successful insertion of the nail. The outcomes noted from the 4 patients are collated, with several complications occurring including delayed femoral union, fixed flexion deformity of the hip, persisting pain and quadriceps weakness. Those with Ollier's disease underwent an increased rate of distraction to prevent premature healing. The implications of long-term bisphosphonate therapy in OI are discussed with regards to the risk of delayed femoral union and intra-operative fracture. Conclusions. Intramedullary femoral lengthening in pathological bone disease is possible, but the surgeon needs to give attention to certain details. The regenerate formation is based on the background pathology irrespective of the hardware used. There is much more compliance with the nail technique


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_20 | Pages 13 - 13
1 Nov 2016
Nam D Wang Y Whetstone H Alman B
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The T-lymphocyte secreted pro-inflammatory cytokine, interleukin-17F (IL-17F), was found to be a key mediator in the cellular response of the immune system in the early phase of fracture repair but its intracellular signaling processes are currently not known in osteoblasts. The objective of this study was to identify the signaling proteins and crucial gene targets involved in osteoblast activation via IL-17F. It was hypothesised that IL-17F stimulated osteoblast maturation through a novel GSK3beta / beta-catenin independent pathway. Mouse pre-osteoblast cell line (MC3T3-E1) was used for IL-17F or Wnt3a treatment. Desired proteins were detected using western blot analysis (antibodies: Phospho-GSK-3beta (Tyr 216), Phospho-GSK-3beta (Ser9), Runx2/cbfa1, TRAF6, Act1, p-ERK2, p-JNK and p-MAPK, C/EBP-beta and & delta). Gene-specific siRNAs of mouse IL-17Ra, IL-17Rc and a non-targeting siRNA (control) were utilised. MC3T3-E1 were transfected with IL-17Ra, IL-17Rc or Negative Control and treated with IL-17F. Chromatin Immunoprecipitation (ChIP-qPCR) was used to evaluate the mouse Runx2 P1 promoter region. IL-17F increased expression of Col1, BSP, Runx2/cbfa1 and osteocalcin in MC3T3-E1 cells. Western blot analysis confirmed expression of known Wnt signaling proteins TRAF6, Act1, p-ERK2, p-JNK and p-MAPK in both IL-17F and Wnt3a treated cultures, including up-regulation of Runx2/cbfa1, a key transcription factor associated with osteoblast differentiation. IL-17F up-regulation of Runx2/cbfa1 appears independent of the Wnt/beta-catenin pathway as phosphorylated GSK-3beta at the Ser9 site was not detected with IL-17F treatment. Despite this, IL-17F treatment still increased expression of Runx2/cbfa1 downstream, lending evidence for a GSK3beta/beta-catenin independent manner of IL-17F stimulated osteogenesis. While IL-17F and Wnt3a both induced expression of C/EBP-delta, only IL-17F treatment induced expression of C/EBP-beta, an upstream transcription factor of Runx2/cbfa1. Further, siRNA knock down of the IL-17 receptors directly decreased Act1, C/EBP-beta and Runx2/cfba1 expression. By ChIP analysis, IL-17F was shown to upregulate C/EBP-beta expression and stimulated its binding to the P1 Promoter of the Runx2/cbfa1 gene. The C/EBP-beta transcription factor was shown to be a key regulator of early osteogenesis. C/EBP-beta up-regulates Runx2/cbfa1 expression by directly binding to the Runx2/cbfa1 P1 promoter in osteoblasts. C/EBP-beta was activated in the osteoblast by IL-17F but not by Wnt3a adding further support to a novel GSK3beta/beta-catenin independent pathway. Our data shows that IL-17F, a cytokine secreted by T-lymphocytes, stimulates osteoblast maturation through a novel GSK3beta/beta-catenin independent pathway and reveals a crucial interaction between C/EBP-beta and the Runx2/cbfa1 P1 promoter not previously been shown in osteogenesis signaling further


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_8 | Pages 44 - 44
1 Aug 2020
Li Z Geng Z Cui Z Wu S Zhu S Liang Y Yang X
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Surgical failure, mainly caused by loosening implants, causes great mental and physical trauma to patients. Improving the physicochemical properties of implants to achieve favourable osseointegration will continue to be the focus of future research. Strontium (Sr), a trace element, is often incorporated into hydroxyapatite (HA) to improve its osteogenic activity. Our previous studies have shown that miR-21 can promote the osteogenic differentiation of mesenchymal stem cells by the PI3K/β-catenin pathway. The aim of this study is to fabricate a SrHA and miR-21 composite coating and it is expected to have a favorable bone healing capability. Ti discs (20 mm diameter and one mm thickness for the in vitro section) and rods (four mm diameter and seven mm length for the in vivo section) were prepared by machining pure Ti. The Ti cylinders were placed in a Teflon-lined stainless-steel autoclave for treating at 150°C for 24 h to form SrHA layer. The miR-21 was encapsulated in nanocapsules. The miR-21 nanocapsules were mixed with CMCS powder to form a gel-like sample and uniformly coated on the SrHA modifed Ti. Osteoblast-like MG63 cells were cultured on SrHA and miR-21 modified Ti, Cell proliferation activity and osteogenesis-related gene expression were evaluated. A bone defect model was established with mature New Zealand to evaluate the osseointegration. Cylindrical holes (four mm in diameter) were created at the distal femur and tibial plateau. Each rabbit was implanted with four of the aforementioned rods (distal femur and tibial plateau of the hind legs). After implantation for one, two and three months, the rabbits were observed by X-ray and scanned using u-CT. Histological and Immunohistochemical analysis were performed to examine the osteogenic markers. A biomechanical push-in test was used to assess the bone-implant bonding strength. Both SrHA nanoparticles with good superhydrophilicity and miR-21 nanocapsules with uniform sizes were distributed evenly on the surface of the Ti. In vitro experiments revealed that the composite coating was beneficial to osteoblast proliferation, differentiation and mineralization. In vivo evaluations demonstrated that this coating could not only promote the expression of angiogenic factor CD31 but also enhance the expression of osteoblastic genes to facilitate angio-osteogenesis. In addition, the composite coating also showed a decreased RANKL expression compared with the miR-21 coating. As a result, the SrHA/miR-21 composite coating promoted new bone formation and mineralization and thus enhanced osseointegration and bone-implant bonding strength. A homogeneous SrHA and miR-21 composite coating was fabricated by generating pure Ti through a hydrothermal process, followed by adhering miR-21 nanocapsules. This coating combined the favorable physicochemical properties of SrHA and miR-21 that synergistically promoted angiogenesis, osteogenesis, osseointegration, bone mineralization and thus bone-implant bonding strength. This study provided a new strategy for surface modification of biomedical implants


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_8 | Pages 46 - 46
1 Aug 2020
Charbonnier B Baradaran A Harvey E Gilardino M Makhoul N Barralet J
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The treatment of critical-sized bone defects still remains today a challenge, especially when the surrounding soft, vascularized and innervated tissues have been damaged - a lack of revascularization within the injured site leading to physiological disorders, from delayed healing to osteonecrosis. The axial insertion of a vascular bundle (e.g. arterio-venous loop, AVL) within a synthetic bone filler to initiate and promote its revascularization has been foreseen as a promising alternative to the current strategies (e.g., vascularized free flaps) for the regeneration of large bone defects. In a previous work, we showed that the insertion of a vein in a 3D-printed monetite scaffold induced its higher revascularization than AVL, thus a possible simplification of the surgical procedures (no microsurgery required). Going further, we investigate in this study whether or not the presence of a vein could stimulate the formation of mineralized tissue insides a synthetic scaffold filled with bone marrow and implanted in ectopic site. Monetite scaffolds were produced by additive manufacturing according to a reactive 3D-printing technique co-developed by the authors then thoroughly characterized. Animal study was performed on 14 male Wistar rats. After anesthesia and analgesia, a skin medial incision in rat thigh allowed the site on implantation to be exposed. Bone marrow was collected on the opposite femur through a minimally invasive procedure and the implant was soaked with it. For the control group (N=7), the implant was inserted in the incision and the wound was closed whereas the femoral bundle was dissected and the vein inserted in the implant for the experimental group (N=7). After 8 weeks animals were sacrificed, the implant collected and fixed in a 4% paraformaldehyde solution. Explants were characterized by µCT then embedded in poly-methyl methacrylate prior SEM, histology and immunohistochemistry. Images were analyzed with CT-Analyzer (Bruker) and ImageJ (NIH) and statistical analyses were carried out using SPSS (IBM). Implants were successfully 3D-printed with a +150 µm deviation from the initial CAD. As expected, implants were composed of 63%wt monetite and 37%wt unreacted TCP, with a total porosity of 44%. Data suggested that scaffold biodegradation was significantly higher when perfused by a vein. Moreover, the latter allowed for the development of a dense vascular network within the implant, which is far more advanced than for the control group. Finally, although mineralized tissues were observed both inside and outside the implant for both groups, bone formation appeared to be much more important in the experimental one. The ectopic formation of a new mineralized tissue within a monetite implant soaked with bone marrow seems to be highly stimulated by the simple presence of a vein alone. Although AVL have been studied extensively, little is known about the couple angiogenesis/osteogenesis which appears to be a key factor for the regeneration of critical-sized bone defects. Even less is known about the mechanisms that lead to the formation of a new bone tissue, induced by the presence of a vein only. With this in mind, this study could be considered as a proof of concept for further investigations


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_7 | Pages 54 - 54
1 Jul 2020
Epure LM Grant M Mwale F Antoniou J Bolt A Mann K Chou H
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Tungsten has been increasing in demand for use in manufacturing and recently, medical devices, as it imparts flexibility, strength, and conductance of metal alloys. Given the surge in tungsten use, our population may be subjected to elevated exposures. For instance, embolism coils made of tungsten have been shown to degrade in some patients. In a cohort of breast cancer patients who received tungsten-based shielding for intraoperative radiotherapy, urinary tungsten levels remained over tenfold higher 20 months post-surgery. In vivo models have demonstrated that tungsten exposure increases tumor metastasis and enhances the adipogenesis of bone marrow-derived mesenchymal stem cells while inhibiting osteogenesis. We recently determined that when mice are exposed to tungsten [15 ppm] in their drinking water, it bioaccumulates in the intervertebral disc tissue and vertebrae. This study was performed to determine the toxicity of tungsten on intervertebral disc. Bovine nucleus pulposus (bNP) and annulus fibrosus (bAF) cells were isolated from bovine caudal tails. Cells were expanded in flasks then prepared for 3D culturing in alginate beads at a density of 1×10. ∧. 6 cells/mL. Beads were cultured in medium supplemented with increasing tungsten concentrations in the form of sodium tungstate [0, 0.5, 5, 15 ug/mL] for 12 days. A modified GAG assay was performed on the beads to determine proteoglycan content and Western blotting for type II collagen (Col II) synthesis. Cell viability was determined by counting live and dead cells in the beads following incubation with the Live/Dead Viability Assay kit (Thermo Fisher Scientific). Cell numbers in beads at the end of the incubation period was determined using Quant-iT dsDNA Assay Kit (Thermo Fisher Scientific). Tungsten dose-dependently decreased the synthesis of proteoglycan in IVD cells, however, the effect was significant at the highest dose of 15 ug/mL. (n=3). Furthermore, although tungsten decreased the synthesis of Col II in IVD cells, it significantly increased the synthesis of Col I. Upregulation of catabolic enzymes ADAMTS4 and −5 were also observed in IVD cells treated with tungsten (n=3). Upon histological examination of spines from mice treated with tungsten [15 ug/mL] in their drinking water for 30 days, disc heights were diminished and Col I upregulation was observed (n=4). Cell viability was not markedly affected by tungsten in both bNP and bAF cells, but proliferation of bNP cells decreased at higher concentration. Surprisingly, histological examination of IVDs and gene expression analysis demonstrated upregulation of NGF expression in both NP and AF cells. In addition, endplate capillaries showed increases in CGRP and PGP9.5 expression as determined on histological sections of mouse IVDs, suggesting the development of sensory neuron invasion of the disc. We provide evidence that prolonged tungsten exposure can induce disc fibrosis and increase the expression of markers associated with pain. Tungsten toxicity may play a role in disc degeneration disease


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_6 | Pages 147 - 147
1 Jul 2020
Godbout C Nauth A Schemitsch EH Fung B Lad H Watts E Desjardins S Cheung KLT
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The Masquelet or induced membrane technique (IMT) is a two-stage surgical procedure used for the treatment of segmental bone defects. In this technique, the defect is first filled with a polymethyl methacrylate (PMMA) spacer, which triggers the formation of a membrane that will encapsulate the defect. During the second surgery, the spacer is carefully removed and replaced by autologous bone graft while preserving the membrane. This membrane is vascularized, contains growth factors, and provides mechanical stability to the graft, all of which are assumed to prevent graft resorption and promote bone healing. The technique is gaining in popularity and several variations have been introduced in the clinical practice. For instance, orthopaedic surgeons now often include antibiotics in the spacer to treat or prevent infection. However, the consequences of this approach on the properties of the induce membrane are not fully understood. Accordingly, in a small animal model, this study aimed to determine the impact on the induced membrane of impregnating spacers with antibiotics frequently used in the IMT. We surgically created a five-mm segmental defect in the right femur of 25 adult male Sprague Dawley rats. The bone was stabilized with a plate and screws before filling the defect with a PMMA spacer. Animals were divided into five equal groups according to the type and dose of antibiotics impregnated in the spacer: A) no antibiotic (control), B) low-dose tobramycin (1.2 g/40 g of PMMA), C) low-dose vancomycin (1 g/40 g of PMMA), D) high-dose tobramycin (3.6 g/40 g of PMMA), E) high-dose vancomycin (3 g/40 g of PMMA). The animals were euthanized three weeks after surgery and the induced membranes were collected and divided for analysis. We assessed the expression of selected genes (Alpl, Ctgf, Runx2, Tgfb1, Vegfa) within the membrane by quantitative real-time PCR. Moreover, frozen sections of the specimens were used to quantify vascularity by immunohistochemistry (CD31 antigen), proliferative cells by immunofluorescence (Ki-67 antigen), and membrane thickness. Microscopic images of the entire tissue sections were taken and analyzed using FIJI software. Finally, we measured the concentration of vascular endothelial growth factor (VEGF) in the membranes by ELISA. No significant difference was found among the groups regarding the expression of genes related to osteogenesis (Alpl, Runx2), angiogenesis (Vegfa), or synthesis of extracellular matrix (Ctgf, Tgfb1) (n = four or five). Similarly, the density of proliferative cells and blood vessels within the membrane, as well as the membrane thickness, did not vary substantially between the control, low-dose, or high-dose antibiotic groups (n = four or five). The concentration of VEGF was also not significantly influenced by the treatment received (n = four or five). The addition of tobramycin or vancomycin to the spacer, at the defined low and high doses, does not significantly alter the bioactive characteristics of the membrane. These results suggest that orthopaedic surgeons could use antibiotic-impregnated spacers for the IMT without compromising the induced membrane and potentially bone healing


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_6 | Pages 104 - 104
1 Jul 2020
Goodman S Lin T Pajarinen J Yao Z
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Mesenchymal stem cells (MSCs) are capable of forming bone, cartilage and other mesenchymal tissues but are also important modulators of innate and adaptive immune responses. We have capitalized on these important functions to mitigate adverse responses when bone is exposed to pathogen-associated molecular patterns (PAMPs), damage-associated molecular patterns (DAMPs), or prolonged pro-inflammatory cytokines. Our goal was to optimize osteogenesis and mitigate persistent undesired inflammation by: 1. preconditioning MSCs by short term exposure to lipopolysaccharide (LPS) and Tumor Necrosis Factor alpha (TNF-α), 2. genetic modification of MSCs to overexpress Interleukin 4 (IL-4) either constitutively, or as NFκB-responsive IL-4 over-expression cells, and 3. training the MSCs (innate immune memory) by repeated stimulation with LPS. In the first experiment, bone marrow MSCs and macrophages were isolated from femurs and tibias of C57BL/6 mice. MSCs (1×104 cells) were seeded in 24-well transwell plates in the bottom chamber with MSC growth medium. MSCs were treated with 20 ng/ml TNF-α and 1–20 μg/ml LPS for three days. Primary macrophages (2 × 103 cells) were seeded to the insert of a separate transwell plate and polarized into the M1 phenotype. At day four, MSCs and macrophages were washed and the inserts with M1 macrophages were moved to the plates containing preconditioned MSCs at the bottom of the well. Co-culture was carried out in MSC growth medium for 24h. In the second experiment, bone marrow derived macrophages and MSCs were isolated from femora and tibiae of Balb/c male mice. 5×104 macrophages and 1×104 MSCs were seeded in the bottom well of the 24-well transwell plate. The upper chambers were seeded with unmodified MSCs, MSCs preconditioned with 20 ng/ml TNF-α and 20 mg/ml LPS for 3 days, NFκB-IL4 secreting MSCs (all 5×104 cells), or controls without MSCs. Co-culture was carried out in mixed osteogenic-macrophage media with clinically relevant polyethylene or titanium alloy particles. In the third experiment, bone marrow MSCs and macrophages were collected from femurs and tibias of C57BL/6 male mice. The MSCs were stimulated by LPS, washed out for five days, and re-stimulated by LPS in co-culture with macrophages. First, preconditioned MSCs enhanced anti-inflammatory M2 macrophage (Arginase 1 and CD206) expression, decreased pro-inflammatory M1 macrophage (TNF-α/IL-1Ra ratio) expression, and increased osteogenic markers (alkaline phosphatase expression and matrix mineralization) in co-culture. Second, NFκB-IL4 secreting MSCs decreased pro-inflammatory M1 (TNF-α), increased anti-inflammatory M2 (Arg1, IL-1ra) expression, and enhanced the expression of osteogenic factors Runx2 and alkaline phosphatase, in the presence of particles, compared to other groups. Third, LPS-trained MSCs increased anti-inflammatory (Arginase1 and CD206), and decreased the proinflammatory (TNF-α, IL1b, iNOS, and IL6) marker expression in MSC/macrophage co-culture. Transforming MSCs via the techniques of preconditioning, genetic modification, or training (innate immune memory) can modulate/convert a potentially injurious microenvironment to an anti-inflammatory pro-reconstructive milieu. These effects are highly relevant for bone healing in the presence of adverse stimuli. These concepts using transformed MSCs could also be extended to other organ systems subjected to potentially damaging agents


Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_15 | Pages 59 - 59
1 Dec 2015
Neves P Costa L Encernação A Guitian F Pereira A Barreira P Serrano P Silva M Leite P Sousa R
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Evaluation of the effectiveness of biodegradable bone substitute with high doses of antibiotics in cavitary osteomyelitis and infected nonunions. The authors evaluated 8 cases, 5 of them related to osteomyelitis with bone sequestration and other 3 regarding infected nonunions. All of them had in common the persistence of infection after antibiotic therapy. All infections were confirmed by microbiological studies. In all cases the surgeons conducted a thorough surgical debridement and filling of bone defects with Herafill®. Later a tight clinical, analytical and imagiological control was performed. Five of the cases were a success with simultaneous healing of the bone loss and treatment of the infection. These corresponded to the cases of cavitary osteomyelitis. In the remaining 3 cases, despite infection eradication, union was not achieved and additional surgical procedures were required for definitive treatment of nonunion. In the treatment of bone infection, use of high doses of antibiotics at the site is a consensus as it allows eradication of the infection with lower systemic effects. With the emergence of biodegradable bone substitutes, the need for a new surgical intervention for their removal can be avoided. Properties of calcium sulfate and calcium carbonate stimulate osteogenesis at the site, allowing their absorption and replacement by bone matrix. These properties make them ideal to usage in cases of cavitary bone defects. Our experience supports the idea that the use of high doses of antibiotics locally permits remission of the infection. However, when this is implemented through a bone substitute, it is possible to achieve osteogenesis in bony cavities. Nevertheless, when applied to infected nonunions, their role seems to be limited to the eradication of the infection


The Bone & Joint Journal
Vol. 106-B, Issue 3 | Pages 293 - 302
1 Mar 2024
Vogt B Lueckingsmeier M Gosheger G Laufer A Toporowski G Antfang C Roedl R Frommer A

Aims

As an alternative to external fixators, intramedullary lengthening nails (ILNs) can be employed for distraction osteogenesis. While previous studies have demonstrated that typical complications of external devices, such as soft-tissue tethering, and pin site infection can be avoided with ILNs, there is a lack of studies that exclusively investigated tibial distraction osteogenesis with motorized ILNs inserted via an antegrade approach.

Methods

A total of 58 patients (median age 17 years (interquartile range (IQR) 15 to 21)) treated by unilateral tibial distraction osteogenesis for a median leg length discrepancy of 41 mm (IQR 34 to 53), and nine patients with disproportionate short stature treated by bilateral simultaneous tibial distraction osteogenesis, with magnetically controlled motorized ILNs inserted via an antegrade approach, were retrospectively analyzed. The median follow-up was 37 months (IQR 30 to 51). Outcome measurements were accuracy, precision, reliability, bone healing, complications, and patient-reported outcome assessed by the Limb Deformity-Scoliosis Research Society Score (LD-SRS-30).


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 289 - 289
1 Mar 2013
Ogawa K
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Introduction. Fracture of the proximal femur frequently occur in children with osteogenesis imperfecta(O.I.) or fibrous dysplasia and may lead to progressive coxa vara and a “shepherds crook” deformity. In adults, these changes introduce difficulties that are not ordinarily encountered with routine osteosynthesis. There is minimal literature on this topic and the cases reported are few in number. Objective. The purpose of this case report was to describe a intertrochanteric fracture in a elderly woman with O.I. successfully treated by 115 degrees hip osteotomy plate and cannulated screws. Methods. We present a case of a 82-year-old female who was injured by falling. She had O.I. type â�£ A according to Sillence. Radiographs showed a intertrochanteric fracture of the femur with severe deformity. The femoral shaft had 25 degrees angular deformity and moderate rotation at the proximal. The angle between femoral neck and shaft was 105 degrees (severe coxa vara) and the proximal femur had a “shepherds crook” deformity (See Figure 1). She had presented 70 years previously ipsilateral fractures of the femur which had healed. These mal-united fracture involved anatomical changes such as medicalization of the femoral canal and intramedullary remodeling and sclerosis (See Figure 2). Recognizing the anatomical changes before and during surgery, standard dynamic hip screw or AO angled blade plate could not fit the femur and not provide stability. Using 115 degrees hip osteotomy plate and cannulated screws, osteosynthesis was performed (See Figure 3). Results. Twelve months postoperatively, the fracture united without complications and the patient felt comfortable and satisfied with gait. Conclusion. An unusual case was presented in which a 82-year-old woman was successfully treated with 115 degrees hip osteotomy plate and cannulated screws for a intertrochanteric fracture of the femur with osteogenesis imperfecta. Standard plate osteosynthesis was unlikely to provide sufficient stable fixation in this case


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVIII | Pages 2 - 2
1 Sep 2012
Li R Qamirani E Atesok K Nauth A Wang S Li C Schemitsch EH
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Purpose. Angiogenesis and osteogenesis are essential for bone growth, fracture repair, and bone remodeling. VEGF has an important role in bone repair by promoting angiogenesis and osteogenesis. In our previous study, endothelial progenitor cells (EPCs) promoted bone healing in a rat segmental bone defect as confirmed by radiological, histological and microCT evaluations (Atesok, Li, Schemitsch 2010); EPC treatment of fractures resulted in a significantly higher strength by biomechanical examination (Li, Schemitsch 2010). In addition, cell-based VEGF gene transfer has been effective in the treatment of segmental bone defects in a rabbit model (Li, Schemitsch et al 2009); Purpose of this study: Evaluation of VEGF gene expression after EPC local therapy for a rat segmental bone defect. Method. Rat bone marrow-derived EPCs were isolated from the rat bone marrow by the Ficoll-paque gradient centrifuge technique. The EPCs were cultured for 7 to 10 days in endothelial cell growth medium with supplements (EGM-2-MV-SingleQuots, Clonetics). and collected for treatment of the rat segmental bone defect. EPCs were identified by immunocytochemistry staining with primary antibodies for CD34, CD133, FLK-1, and vWF. A total of fifty six rats were studied. A five millimeter segmental bone defect was created in the middle 1/3 of each femur followed by mini plate fixation. The treatment group received 1×106 EPCs locally at the bone defect and control animals received saline only. Seven control and seven EPC treated rats were included in each group at 1, 2, 3 and 10 weeks. Animals were sacrificed at the end of the treatment period, and specimens from the fracture gap area were collected and immediately frozen. Rat VEGF mRNA was measured by reverse transcriptase-polymerase chain reaction (RT-PCR) and quantified by VisionWorksLS. All measurements were performed in triplicate. Results. Cultured EPCs at 1 week showed positive staining for CD34, CD133, Flk-1 and vWf markers. The EPC group had a greater VEGF expression than the control group at week 1, 2 and 3 but not at week 10. Three VEGF isoforms were detected in this rat model: VEGF120, VEGF164 and VEGF188. VEGF120 and VEGF164 levels peaked at two weeks, while VEGF188 levels peaked at three weeks. All three VEGF isoform levels were low at ten weeks. Conclusion. EPC-based therapy for a segmental bone defect results in increased VEGF expression during the early period of fracture repair. In addition, the specific VEGF isoform may be a key regulator of the bone healing process. These findings demonstrate that EPCs promote fracture healing by increasing VEGF levels and thus stimulating angiogenesis, a process that is essential for early callus formation and bone regeneration


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_23 | Pages 67 - 67
1 Dec 2016
Thorrez L Putzeys G Kathleen C Boudewijns M Christiane D
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Aim. To prevent infections after orthopaedic surgery, intravenous antibiotics are administered perioperatively. Cefazolin is widely used as the prophylactic antibiotic of choice. Systemic antibiotic therapy may however be less effective in longstanding surgery where bone allografts are used. Bone chips have been shown to be an effective carrier for certain types of antibiotics and may provide the necessary local antibiotic levels for prophylaxis. To be efficient a prolonged release is required. In contrast to vancomycin with proven efficient prolonged release from Osteomycin, this has not been described for cefazolin. We developed a protocol to bind cefazolin to bone chips by means of a hydrogel composed of proteins naturally present in the human body. Method. Three types of bone chips were evaluated: fresh frozen, decellularized frozen and decellularized lyophilized. Bone chips were incubated with 20 mg/ml cefazolin or treated with liquid hydrogel containing either 1 mg/ml fibrin or 1 mg/ml collagen and 20 mg/ml cefazolin. The cefazolin hydrogel was distributed in the porous structure by short vacuum treatment. Bone chips with cefazolin but without hydrogel were either incubated for 20 min- 4h or also treated with vacuum. Cefazolin elution of bone chips was carried out in fetal bovine serum and analysed by Ultra Performance Liquid Chromatography – Diode Array Detection. Results. Soaking of bone chips without hydrogel resulted in a quick release of cefazolin, which was limited to 4 hours. When vacuum was applied elution of >1 µg/ml cefazolin was measured for up to 36 hours. Combination with collagen hydrogel resulted in a higher cefazolin concentration released at 24 hours (3.9 vs 0.3 µg/ml), but not in a prolonged release. However, combination of decellularized frozen bone chips with fibrin hydrogel resulted in an initial release of 533 µg/ml followed by a gradual decline reaching the minimal inhibitory concentration for S. aureus at 72 hours (1.7 µg/ml), while not measurable anymore after 92 hours. Conclusions. Processed bone chips with hydrogel-cefazolin showed a markedly prolonged cefazolin release. When combined with a fibrin hydrogel, high initial peak levels of cefazolin were obtained, followed by a decreasing release over the following three days. This elution profile seems desirable, with high initial levels to maximize anti-bacterial action and low levels for a limited time to stimulate osteogenesis. Further preclinical studies are warranted to show effectiveness of hydrogel-cefazolin impregnated bone chips


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_22 | Pages 20 - 20
1 Dec 2016
Haddad F
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Periprosthetic fractures after total hip arthroplasty lead to considerable morbidity in terms of loss of component fixation, bone loss and subsequent functional compromise. The prevention, early recognition and appropriate management of such fractures are therefore critical. The pathogenesis of periprosthetic factors is multi-factorial. There are a number of intrinsic patient influences such as poor bone stock, biomechanics and compliance. There are also a host of extrinsic factors over which the surgeon has more control. The key tenets for fracture avoidance include careful planning, identifying the risk, choosing the correct implant, understanding the anatomy, and using appropriate surgical technique. There are a number of recognised risk factors for periprosthetic hip fractures The prevalence of intraoperative fractures during total hip arthroplasty is higher in the patient with osteopenia / osteoporosis. Other conditions causing increased bone fragility, such as osteomalacia, Paget's disease, osteopetrosis, and osteogenesis imperfecta are also at a higher risk of intraoperative fracture. The use of more and more press fit cementless components has also increased the number of periprosthetic femoral fractures because of the force required to obtain such a fit. Complex deformities of the proximal femur, particularly when associated with a narrow medullary canal, may also increase the risk of intraoperative fractures. Revision surgery is associated with a higher risk of intraoperative fracture than primary hip replacement surgery. These fractures typically occur during hip dislocation, cement extraction, or reaming through old cement. Other risk factors for postoperative femoral fractures following total hip replacement include loosening of the prosthesis with cortical bone loss, local osteolysis, stress risers within the cortex, such as old screw holes, the ends of plates, or impingement of a loose stem against the lateral femoral cortex. The management of periprosthetic fractures requires appropriate preoperative imaging, planning and templating, the availability of the necessary expertise and equipment, and knowledge of the potential pitfalls so that these can be avoided both intraoperatively and in follow-up. There is a danger that these cases fall between the expertise of the trauma surgeon and that of the revision arthroplasty surgeon. The past two decades have afforded us clear treatment algorithms based on fracture location, component fixation and the available bone stock. We still nevertheless face the enduring challenge of an elderly population with a high level of comorbidity who struggle to rehabilitate after such injuries. Perioperative optimization is critical as we have seen prolonged hospital stays, high rates of systemic complications and a significant short term mortality in this cohort. We have also been presented with new difficult fracture patterns around anatomic cementless stems and in relation to tapered cemented and cementless stems, as well as biologically challenging transverse or oblique fractures at the tip of a stem. In many cases, fixation techniques are biomechanically and biologically doomed to fail and intramedullary stability, achieved through complex revision is required. The sequelae of periprosthetic fractures include the financial cost of fixation or revision surgery, the associated morbidity and mortality in an elderly frail population, the difficulty with mobilization if the patient cannot fully weight bear, and a poor functional outcome in a proportion of cases. The battle over which patients or fractures require fixation and which require revision surgery continues