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Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_8 | Pages 107 - 107
11 Apr 2023
Lee E Ko J Park S Moon J Im G
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We found that adipose stem cells are poorly differentiated into bone and that their ability to differentiate into bone varies from cell line to cell line. The osteogenic differentiation ability of the adipose stem cell lines was distinguished through Alzarin Red Staining, and the cell lines that performed well and those that did not were subjected to RNA-seq analysis. The selected gene GSTT1 (glutathione S-transferase theta-1) gene is a member of a protein superfamily that catalyzes the conjugation of reduced glutathione to a variety of hydrophilic and hydrophobic compounds. The purpose of this study is to treat avascular necrosis and bone defect by improving bone regeneration with adipose stem cells introduced with a new GSTT1 gene related to osteogenic differentiation of adipose stem cells. In addition, the GSTT1 gene has the potential as a genetic marker that can select a specific cell line in the development of an adipose stem cell bone regeneration drug.

Total RNA was extracted from each sample using the TRIzol reagent. Its concentration and purity were determined based on A260 and A260/A280, respectively, using a spectrophotometer. RNA sequencing library of each sample was prepared using a TruSeq RNA Library Prep Kit. RNA-seq experiments were performed for hADSCs. Cells were transfected with either GSTT1 at 100 nM or siControl (scramble control) by electroporation using a 1050 pulse voltage for 30 ms with 2 pulses using a 10 μl pipette tip.

The purpose of this study is to discover genetic markers that can promote osteogenic differentiation of adipose stem cells (hADSCs) through mRNA-seq gene analysis. The selected GSTT1 gene was found to be associated with the enhancement of osteogenic differentiation of adipose stem cells. siRNA against GSTT1 reduced osteogenic differentiation of hADSCs, whereas GSTT1 overexpression enhanced osteogenic differentiation of hADSCs under osteogenic conditions.

In this study, GSTT1 transgenic adipose stem cells could be used in regenerative medicine to improve bone differentiation. In addition, the GSTT1 gene has important significance as a marker for selecting adipose stem cells with potential for bone differentiation in the development of a therapeutic agent for bone regeneration cells.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_7 | Pages 142 - 142
4 Apr 2023
Ko J Lee E Cha H Im G
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In this study, we developed biocompatible adhesive which enables implanted chondrogenic-enhanced hASCs being strongly fixed to the lesion site of defected cartilage.

The bioengineered mussel adhesive protein (MAP) was produced and purified using a bacterial expression system as previously reported. The cell encapsulated coacervate was formulated with two polyelectrolyte, the MAP and 723kDa hyaluronic acid (HA). MAP formed liquid microdroplets with HA and subsequently gelated into microparticles, which is highly viscous and strongly adhesive.

The MAP with chondro-induced hASCs were implanted on the osteochondral defect created in the patellar groove/condyle of OA-induced rabbits. Rabbits were allocated to three different groups as follows: Group1 – Fibrin only; Group2 – Fibrin with hASCs (1.5×106 chondro-induced hASCs); Group3; MAP with hASCs.

The implanted cells were labeled with a fluorescent dye for in vivo visualization. After 35 days, fluorescent signals were more potently detected for MAP with hASCs group than Fibrin with hASCs group in osteochondral defect model. Moreover, histological assessment showed that MAP with hASCs group had the best healing and covered with hyaline cartilage-like tissue. The staining image shows that MAP with hASCs group were filled with perfectly differentiated chondrocytes. Although Fibrin with hASCs group had better healing than fibrin only group, it was filled with fibrous cartilage which owes its flexibility and toughness. As MAP with hASCs group has higher possibility of differentiating to complete cartilage, Fibrin only group and Fibrin with hASCs group have failed to treat OA by rehabilitating cartilage. In order to clarify the evidence of remaining human cell proving efficacy of newly developed bioadhesive, human nuclear staining was proceeded with sectioned rabbit cartilage tissue. The results explicitly showed MAP with hASCs group have retained more human cells than Fibrin only and Fibrin with hASCs groups.

We investigated the waterproof bioadhesive supporting transplanted cells to attach to defect lengthily in harsh environment, which prevents cells from leaked to other region of cartilage. Collectively, the newly developed bio-adhesive, MAP, could be successfully applied in OA treatment as a waterproof bioadhesive with the capability of the strong adhesion to target defect sites.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_9 | Pages 16 - 16
1 Jun 2021
Roche C Simmons C Polakovic S Schoch B Parsons M Aibinder W Watling J Ko J Gobbato B Throckmorton T Routman H
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Introduction

Clinical decision support tools are software that match the input characteristics of an individual patient to an established knowledge base to create patient-specific assessments that support and better inform individualized healthcare decisions. Clinical decision support tools can facilitate better evidence-based care and offer the potential for improved treatment quality and selection, shared decision making, while also standardizing patient expectations.

Methods

Predict+ is a novel, clinical decision support tool that leverages clinical data from the Exactech Equinoxe shoulder clinical outcomes database, which is composed of >11,000 shoulder arthroplasty patients using one specific implant type from more than 30 different clinical sites using standardized forms. Predict+ utilizes multiple coordinated and locked supervised machine learning algorithms to make patient-specific predictions of 7 outcome measures at multiple postoperative timepoints (from 3 months to 7 years after surgery) using as few as 19 preoperative inputs. Predict+ algorithms predictive accuracy for the 7 clinical outcome measures for each of aTSA and rTSA were quantified using the mean absolute error and the area under the receiver operating curve (AUROC).


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_15 | Pages 34 - 34
1 Nov 2018
Lian W Ko J Wang F
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Sclerostin (SOST) is an endogenous inhibitor of Wnt/β-catenin signalling pathway to impair osteogenic differentiation and bone anabolism. SOST immunotherapy like monoclonal antibody has been observed to control bone remodeling and regeneration. This study is aimed to develop a SOST vaccine and test its protective effects on estrogen deficiency-induced bone loss in mice. Gene sequences coded SOST peptide putative targeting Wnt co-receptor LRP5 were cloned and constructed into vectors expressing Fc fragment to produced SOST-Fc fusion protein. Mice were subcutaneously injected SOST-Fc to boost anti-SOST antibody. Bone mineral density, microstructure, and mechanical property were quantified using μCT scanning and material testing system. Serum bone formation and resorption markers and anti-SOST levels were measured using ELISA. SOST-Fc injections significantly increased serum anti-SOST antibody levels but reduced serum SOST concentrations. SOST-Fc vaccination significantly reduced estrogen deficiency-induced serum bone resorption markers CTX-1 increased serum bone formation marker osteocalcin. Of note, it significantly alleviated the severity of estrogen-induced loss of bone mineral density, trabecular morphometric properties, and biomechanical forces of bone tissue. Mechanistically, SOSF-Fc vaccination attenuated trabecular loss histopathology and restored immunostaining of Wnt pathway like Wnt3a, β-catenin, and TCF4 in bone tissue along with increased serum osteoclast inhibitor OPG levels but decreased serum osteoclast enhancer RANKL concentrations. Taken together, SOST-Fc vaccination boosts anti-SOST antibody to neutralize SOST and mitigates the estrogen deficiency-induced bone mass and microstructure deterioration through preserving Wnt signalling. This study highlights an innovative remedial potential of SOST vaccine for preventing osteoporosis.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_15 | Pages 68 - 68
1 Nov 2018
Tsai T Lian W Wang F Ko J
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Subacromial bursa fibrosis are linked to rotator cuff lesion with shoulder stiffness; however, the mechanism underlying this shoulder disorder remain elusive. MicroRNA-29s (miR-29s) are emerging fibrosis inhibitor targeting fibrogenic matrices during tissue fibrosis. This study is aimed to investigate clinical relevance and function of miR-29 signalling to subacromial bursa homeostasis in shoulder stiffness. Subacromial bursa in patients with rotator cuff lesion with or without shoulder stiffness who required open acromioplasty were harvested for assessing fibrosis histopathology using Manson's trichrome staining. Expressions of proinflammatory cytokines, fibrotic matrices, and miR-29s were quantified using RT-PCR and in situ hybridization. Range of motion and pain scores of the stiffness group were higher than those of non-stiffness group. Upregulated proinflammatory cytokines (IL-1β, IL-6, and TNF-α) and fibrotic matrices (collagen 1α1, 3α1, and 4α1) but decreased miR-29a and b expression existed in the stiffness group. Affected tissues exhibited severe fibrotic matrix accumulation, synovial hyperangiogenesis, hyperplasia, and strong miR-29a transcripts. In vitro, IL-1β rather than IL-6 and TNF-α decreased miR-29a expression of subacromial bursa fibroblasts. miR-29a knockdown escalated fibrotic matrix expression, whereas forced miR-29a expression alleviated the IL-1β-induced fibrotic matrix expression. Of interest, miR-29a transgenic mice displayed moderate responses to supraspinatus and infraspinatus tenotomy-induce fibrosis and gait irregularity of affected shoulders. Weak miR-29 signalling causes excessive fibrosis and remodelling in subacromial bursa and ultimately increases the prevalence of shoulder stiffness. This study reveals a new mechanistic underlying shoulder stiffness and highlights that sustained miR-29a potentially ameliorates the severity and function of stiff shoulder.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_15 | Pages 16 - 16
1 Nov 2018
Chen Y Lian W Ko J Wang F
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Fatty marrow and bone loss are prominent pathologic features of osteoporosis. DNA hypermethylation shifts mesenchymal stem cells towards adipocytes impairing bone formation. Brown adipocytes produce growth factors advantageous to osteogenesis, whereas white adipocytes secrete pro-inflammatory cytokines deleterious to bone homeostasis. We assess DNA methylation inhibitor action to brown and white adipocyte formation in marrow fat of osteoporotic skeletons. Osteoporotic skeletons in mice were induced by glucocorticoid, ovariectomy or ageing. Marrow adipose volume and bone structure were quantified using OsO4 contrast-μCT imaging. Brown and white adipocytes were probed using immunostaining, RT-PCR and primary bone-marrow mesenchymal stem cell cultures. Abundant marrow fat and spare trabecular bone existed in osteoporotic skeletons. Osteoporosis increased expressions of general adipogenic markers PPARγ2 and FABP4 and white adipocyte markers TCF21 and HOXc9, whereas expressions of brown adipocyte markers PGC-1α and UCP-1 and osteogenic markers Runx2 and osteocalcin were significantly decreased. Number of UCP-1 immunostaining-positive brown adipocytes also reduced in osteoporotic bone. In vitro, DNA methylation inhibitor 5'-aza-deoxycystidine significantly increased brown adipocyte formation and osteogenic differentiation and mitigated dexamethasone-induced white adipocyte formation in mesenchymal stem cells. 5'-aza-deoxycystidine control of brown adipogenesis and white fat formation appeared to be regulated by increasing Wnt3a/β-catenin and reducing Dkk1. Disintegrated brown adipocyte and white fat cell differentiation contribute to osteoporosis pathogenesis. Maintaining DNA hypomethylation promotes Wnt signalling and brown adipocyte differentiation facilitating osteogenic differentiation. This study shed a new light to the contribution of brown adipocytic cells to bone metabolism during osteoporosis.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_5 | Pages 35 - 35
1 Apr 2018
Ko J Wang F Lee S Siu K Chou W Wang C
Full Access

Introduction

Blood loss after TKA varied, but not uncommon with up to 1500 ml or a decrease in hemoglobin of 3–4 g/dL. In addition to improving prosthetic alignment, computer-assisted TKAs also contribute to reduced operative blood loss and systemic emboli. These observations imply that navigation TKAs may cause less microvascular endothelial damage than conventional TKAs. Cell adhesion molecules (CAMs) have been employed as markers for endothelial or vascular damage. We hypothesized serum levels of CAMs in patients receiving navigation TKAs may be different from those receiving conventional TKAs.

Material and Methods

A prospective comparative study, enrolling 87 patients with osteoarthritic knees was conducted. There were 54 navigation TKAs and 33 conventional TKAs. Levels of cell adhesion molecules (CAM) in sera and hemovac drainage were measured by ELISA before and 24 hours after the surgery. Hb and Ht were checked pre- and post-operatively. The blood loss was calculated though the formula by Nadler and Sehat et al.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_8 | Pages 80 - 80
1 Apr 2017
Wang F Sun Y Chen Y Ko J
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Background

Long-term glucocorticoid treatment increases incidence of osteoporotic or osteonecrotic disorders. Excessive bone loss and marrow fat accumulation are prominent features of glucocorticoid-induced osteoporosis. MicroRNA-29 (miR-29) family members reportedly modulate lineage commitment of stem cells. This study was undertaken to define the biological roles of miR-29a in skeletal and fat metabolism in the pathogenesis of glucocorticoid-induced osteoporosis.

Methods

Osteoblast-specific miR-29a transgenic mice (Tg) driven by osteocalcin promoter (C57BL/6JNarl-TgOCN-mir29a) or wild-type (WT) mice were given methylprednisolone. Bone mass, trabecular and cortical bone microarchitecture were assessed by μCT. Comparative mRNA and protein expression was quantified by RT-PCR and immunoblotting. Primary bone-marrow mesenchymal cells were isolated for elucidating ex vivo osteogenic and adipogenic differentiation capacity.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_8 | Pages 81 - 81
1 Apr 2017
Cheng Y Wang F Su Y Ko J
Full Access

Background

MicroRNAs are non-coding small RNAs that reportedly regulate mRNA targets or protein translation of various tissues in physiological and pathological contexts. This study was undertaken to characterise the contributions of microRNA-29a (miR-29a) to the progression of estrogen deficiency-mediated excessive osteoclast resorption and bone loss.

Methods

Osteoblast-specific transgenic mice overexpressing miR-29a driven by osteocalcin promoter (C57BL/6JNarl-TgOCN-mir29a) or wild-type mice were subjected to bilateral ovariectomy. Bone mineral density, trabecular microarchitecture and osteoclast distribution was quantified by μCT and histomorphometry. Primary CD11b+CSF-1R+ preosteoclasts were isolated for detecting ex vivo osteoclast differentiation. Gene expression and transcription factor-promoter interaction were quantified by RT-PCR and chromatin immunoprecipitation.


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_16 | Pages 33 - 33
1 Oct 2014
Siu K Ko J Wang F Wang C Chou W
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D-dimer is one of the useful laboratory tests to evaluate the incidence of venous thromboembolism (VTE) after the total knee arthroplasty (TKA). The most recent guideline for the prophylaxis of VTE points out the surgical procedure itself is a major risk factor for developing VTE.

Only a few literatures discuss the relationship of surgical procedures and the risk of venous thromboembolism. We therefore prospectively compare the difference of the perioperative plasma D-dimer levels between the patients undergoing navigation and convention TKA.

Two hundred consecutive total knee arthroplasties were performed between September 2011 and March 2013. The patients were randomised according to their registration to the orthopaedic clinic. Ninety-six patients (100 knees) underwent a navigation-assisted TKA and ninety-four patients (100 knees) had a conventional TKA. No intramedullary violation was done in the navigation-assisted TKA, while the intramedullary femoral guiding was adapted in the conventional group.

Pre-operative and post-operation day 1 plasma D-dimer levels were recorded and evaluated using Mann-Whitney U test. There was no difference in the demographic data and pre-operative D-dimer between the two groups (p=0.443). Significantly lower D-dimer levels on the post-operative day 1 were noted in the navigation group, when compared with the conventional group. (6.0 ± 4.4 mg/L vs 11.3 ± 9.6 mg/L, p = 0.000).

We demonstrated that lower D-dimer level is developed after the navigation-assisted TKA than the conventional one. Less incidence of VTE is expected and the finding may help to explain the fact that less systemic emboli in the navigation assisted TKA.


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_11 | Pages 338 - 338
1 Jul 2014
Wang F Wang L Ko J
Full Access

Summary Statement

Increased Dkk-1 signaling is associated with OA occurrence and joint microenvironment damage. Interruption of Dkk1 action is beneficial to improve OA knees.

Introduction

Osteoarthritis (OA) is a leading cause of disability and healthcare financial burden for total knee arthroplasty, rehabilitation, and disability. Inappropriate mechanical stress, immunological, or biochemical regulation reportedly disturbs homeostasis among cartilage, synovium and subchondral bone microstructure that contributes to OA pathogenesis. Control of joint-deleterious factor action is an emerging strategy to ameliorate OA-induced joint deterioration. Dickkopf-1 (Dkk-1) is a potent inhibitor for Wnt/β-catenin signaling regulation of tissue development and remodeling in physiological or pathological contexts. Dkk-1 also acts as a master deleterious factor that represses osteoblast differentiation capacity and bone repair. Associations among Dkk-1 expression, chondrocyte fate, synovial fibroblast behavior or OA incidence are merit of characterization.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 422 - 422
1 Nov 2011
Wang C Wang F Ko J Huang S Chen J
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The effect of shockwave in osteonecrosis of the femoral head (ONFH) is poorly understood. The purpose of this study was to investigate the regeneration effects of shockwave in ONFH.

This study consisted of 14 femoral heads from 14 patients undergoing total hip arthroplasty for ONFH. Seven patients with seven hips who received shockwave prior to surgery were designated as the study group, whereas, seven patients with seven hips who did not receive shockwave were assigned to the control group. Both groups showed similar demographic characteristics. The femoral heads were investigated with histopathological examination and immunohistochemical analysis with von Willebrand factor (vWF), VEGF, platelet endothelial cell adhesion molecule-1 (PECAM-1) also referred to as (CD 31) and vascular cell adhesion molecule (VCAM) for angiogenesis, and with proliferation cell nuclear antigen (PCNA), Dickkopf-1 (DKK1) and Winless 3a (Wnt 3) for bone remodelling and regeneration.

In histopathological examination, the study group showed significantly more viable bone and less necrotic bone, higher cell concentration and more cell activities including phagocytosis than the control group. In immunohistochemical analysis, the study group showed significant increases in vWF (P< 0.01), VEGF (P¼0.0012) and CD 31 (P¼0.0023), Wnt3 (P¼0.008) and PCNA (P¼0.0011), and decreases in VCAM (P¼0.0013) and DKK1 (P¼0.0007) than the control group.

Shockwave treatment significantly promotes angiogenesis and bone remodelling than the control. It appears that application of shockwave results in regeneration effects in hips with ONFH.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 107 - 107
1 Mar 2010
Choy W Ahn J Ko J
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Purpose: The purpose of this study was to evaluate clinical and radiological outcomes after cementless bipolar hemiar-throplasty in elderly patients with femoral neck fractures.

Materials and Methods: Eighty hips – all in patients greater than 70 years of age – were followed for more than 2 years after undergoing cementless bipolar hemi-arthroplasty with a tapered rectangular cementless stem (Lima SPH-C2®). The mean age was 76 years, and the mean follow-up period was 37 months. The Harris hip score and postoperative hip pain were analyzed clinically. Femoral bone types were classified according to Dorr method. The radiological results were assessed using various radiological indices.

Results: At last follow-up, the mean Harris hip score was 80.2 points. There were 5 cases of groin pain, 4 (5.0%) mild and 1 (1.3%) moderate and 7 cases of thigh pain, 6 (7.5%) mild and 1 (1.3%) moderate. Fifty-five cases (68.7%) showed no decrease in ambulation capacity postoperatively. Patients have type A bone types in 13 cases(16.2%), type B in 51 cases(63.7%) and type C in 16 cases(20.0%). Radiologically, there were 47 cases (58.7%) of bone ingrowth and 33 cases (41.3%) of stable fibrous fixation. There were no cases of osteolysis, and 30 cases (37.5%) exhibited new bone formation around the stem. All stems were stable without significant alignment change or progressive subsidence.

Conclusion: Short-term outcomes proved to be satisfactory in elderly patients undergoing cementless bipolar hemiarthroplasty for femoral neck fractures. Tapered rectangular stem showed satisfactory results with all bone morphology.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 117 - 117
1 Mar 2010
Choy W Kim K Ko J
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Purpose: To analyze the clinical and radiographic results of patients treated by Oxford minimally invasive unicompartmental knee arthroplasty.

Materials and Methods: We have operated 166 patients 188 knees of minimally invasive unicompartmental knee arthroplasty(Oxford Uni®) from January 2002 to December 2005. The mean ages was 65.3 (44–82) years and 16 cases of male and 150 cases of female. The mean follow-up period was 57 (36–77) months. Preoperative diagnosis were osteoarthritis in 166 cases, avascular necrosis of medial femoral condyle in 20 cases and chondrocalcinosis in 2 cases. The clinical results were evaluated using the HSS knee score and the range of motion of knee preoperatively and at the final follow up. At the final follow up, the ability of the patient to assume the squatting and cross-leg position were checked. The tibiofemoral angle was measured preoperatively and postoperatively. Component loosening, radiolucent lines were checked.

Result: The HSS knee score was 67.5 (52–86) preoperatively and 89.9 (59–100) at the final follow up. The mean preoperative flexion contracture was 6.5° (0–20) and 0.81 (0–5) at the final follow up. Active full flexion was possible within postoperative 2 months. The squatting position was possible in 133 patients (80.1%) and the cross-leg position was possible in 152 patients (91.6%). The tibiofemoral angle was improved varus 1.5° to valgus 4.8°. Complication occurred in 14 cases (7.4%). Meniscal bearing dislocation in 8 cases (4.3%). Tibial components loosenig in 3 cases (1.6%). Femoral components loosening in 2 cases (1.1%). The average time of meniscal bearing dislocation was 11.3 (3–24)months postoperatively. Six cases returned to the predislocation level of activity with the insertion of thicker bearings and 2cases required TKR conversion.

Conclusion: Minimally invasive unicompartmental knee arthroplasty(Oxford Uni®) provides rapid recovery, good pain relief and excellent function quite suitable to Korean life-style. But given the high complicate rate in mid-term results. Oxford Uni® gives less reliability compared with TKR.