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Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_8 | Pages 108 - 108
11 Apr 2023
Turnbull G Picard F Clarke J Li B Shu W
Full Access

As arthroplasty demand grows worldwide, the need for a novel cost-effective treatment option for articular cartilage (AC) defects tailored to individual patients has never been greater. 3D bioprinting can deposit patient cells and other biomaterials in user-defined patterns to build tissue constructs from the “bottom-up,” potentially offering a new treatment for AC defects. The aim of this research was to create bioinks that can be injected or 3D bioprinted to aid osteochondral defect repair using human cells.

Novel composite bioinks were created by mixing different ratios of methacrylated alginate (AlgMA) with methacrylated gelatin (GelMA). Chondrocytes or mesenchymal stem cells (MSCs) were then encapsulated in the bioinks and 3D bioprinted using a custom-built extrusion bioprinter. UV and double-ionic (BaCl2 and CaCl2) crosslinking was deployed following bioprinting to strengthen bioink stability in culture. Chondrocyte and MSC spheroids were also bioprinted to accelerate cell growth and development of ECM in bioprinted constructs.

Excellent viability of chondrocytes and MSCs was seen following bioprinting (>95%) and maintained in culture over 28 days, with accelerated cell growth seen with inclusion of MSC or chondrocyte spheroids in bioinks (p<0.05). Bioprinted 10mm diameter constructs maintained shape in culture over 28 days, whilst construct degradation rates and mechanical properties were improved with addition of AlgMA (p<0.05). Composite bioinks were also injected into in vitro osteochondral defects (OCDs) and crosslinked in situ, with maintained cell viability and repair of osteochondral defects seen over a 14-day period.

In conclusion we developed novel composite AlgMA/GelMA bioinks that can be triple-crosslinked, facilitating dense chondrocyte and MSC growth in constructs following 3D bioprinting. The bioink can be injected or 3D bioprinted to successfully repair in vitro OCDs, offering hope for a new approach to treating AC defects.


The Bone & Joint Journal
Vol. 105-B, Issue 2 | Pages 140 - 147
1 Feb 2023
Fu Z Zhang Z Deng S Yang J Li B Zhang H Liu J

Aims

Eccentric reductions may become concentric through femoral head ‘docking’ (FHD) following closed reduction (CR) for developmental dysplasia of the hip (DDH). However, changes regarding position and morphology through FHD are not well understood. We aimed to assess these changes using serial MRI.

Methods

We reviewed 103 patients with DDH successfully treated by CR and spica casting in a single institution between January 2016 and December 2020. MRI was routinely performed immediately after CR and at the end of each cast. Using MRI, we described the labrum-acetabular cartilage complex (LACC) morphology, and measured the femoral head to triradiate cartilage distance (FTD) on the midcoronal section. A total of 13 hips with initial complete reduction (i.e. FTD < 1 mm) and ten hips with incomplete MRI follow-up were excluded. A total of 86 patients (92 hips) with a FTD > 1 mm were included in the analysis.


Bone & Joint Research
Vol. 12, Issue 1 | Pages 33 - 45
16 Jan 2023
Li B Ding T Chen H Li C Chen B Xu X Huang P Hu F Guo L

Aims

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

Methods

Minus RNA sequencing, fluorescence in situ hybridization, and quantitative real-time polymerase chain reaction (qRT-PCR) were used to detect the expression of circStrn3 in human and mouse OA cartilage tissues and chondrocytes. Chondrocytes were then stimulated to secrete exosomal miR-9-5p by cyclic tensile strain. Intra-articular injection of exosomal miR-9-5p into the model induced by destabilized medial meniscus (DMM) surgery was conducted to alleviate OA progression.


Bone & Joint Research
Vol. 10, Issue 9 | Pages 558 - 570
1 Sep 2021
Li C Peng Z Zhou Y Su Y Bu P Meng X Li B Xu Y

Aims

Developmental dysplasia of the hip (DDH) is a complex musculoskeletal disease that occurs mostly in children. This study aimed to investigate the molecular changes in the hip joint capsule of patients with DDH.

Methods

High-throughput sequencing was used to identify genes that were differentially expressed in hip joint capsules between healthy controls and DDH patients. Biological assays including cell cycle, viability, apoptosis, immunofluorescence, reverse transcription polymerase chain reaction (RT-PCR), and western blotting were performed to determine the roles of the differentially expressed genes in DDH pathology.


The Bone & Joint Journal
Vol. 103-B, Issue 6 | Pages 1021 - 1030
1 Jun 2021
Liu X Dai T Li B Li C Zheng Z Liu Y

Aims

The aim of this meta-analysis was to assess the prognosis after early functional rehabilitation or traditional immobilization in patients who underwent operative or nonoperative treatment for rupture of the Achilles tendon.

Methods

PubMed, Embase, Web of Science, and Cochrane Library were searched for randomized controlled trials (RCTs) from their inception to 3 June 2020, using keywords related to rupture of the Achilles tendon and rehabilitation. Data extraction was undertaken by independent reviewers and subgroup analyses were performed based on the form of treatment. Risk ratios (RRs) and weighted mean differences (WMDs) (with 95% confidence intervals (CIs)) were used as summary association measures.


Bone & Joint Research
Vol. 7, Issue 4 | Pages 298 - 307
1 Apr 2018
Zhang X Bu Y Zhu B Zhao Q Lv Z Li B Liu J

Objectives

The aim of this study was to identify key pathological genes in osteoarthritis (OA).

Methods

We searched and downloaded mRNA expression data from the Gene Expression Omnibus database to identify differentially expressed genes (DEGs) of joint synovial tissues from OA and normal individuals. Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analyses were used to assess the function of identified DEGs. The protein-protein interaction (PPI) network and transcriptional factors (TFs) regulatory network were used to further explore the function of identified DEGs. The quantitative real-time polymerase chain reaction (qRT-PCR) was applied to validate the result of bioinformatics analysis. Electronic validation was performed to verify the expression of selected DEGs. The diagnosis value of identified DEGs was accessed by receiver operating characteristic (ROC) analysis.


Bone & Joint Research
Vol. 6, Issue 9 | Pages 566 - 571
1 Sep 2017
Cheng T Zhang X Hu J Li B Wang Q

Objectives

Surgeons face a substantial risk of infection because of the occupational exposure to blood-borne pathogens (BBPs) from patients undergoing high-risk orthopaedic procedures. This study aimed to determine the seroprevalence of four BBPs among patients undergoing joint arthroplasty in Shanghai, China. In addition, we evaluated the significance of pre-operative screening by calculating a cost-to-benefit ratio.

Methods

A retrospective observational study of pre-operative screening for BBPs, including hepatitis B and C viruses (HBV and HCV), human immunodeficiency virus (HIV) and Treponema pallidum (TP), was conducted for sequential patients in the orthopaedic department of a large urban teaching hospital between 01 January 2009 and 30 May 2016. Medical records were analysed to verify the seroprevalence of these BBPs among the patients stratified by age, gender, local origin, type of surgery, history of previous transfusion and marital status.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIX | Pages 49 - 49
1 Sep 2012
Brown K Li B Guda T Perrien D Guelcher S Wenke J
Full Access

Infection is a common complication of severe open fractures and compromises bone healing. The present standard of care is a two-stage approach comprising of initial placement of antibiotic-impregnated PMMA beads to control infection followed later by bone grafting. Although the systemic antibiotics and PMMA/antibiotic beads control the infection initially, there are often residual bacteria within the wound. After grafting and definitive closure, the implanted graft is placed in an avascular defect and could function as a nidus for infection. Bioactive porous polyurethane (PUR) scaffolds have been shown to improve bone healing by delivering recombinant human bone morphogenetic protein-2 (BMP-2) and reduce infection by delivering antibiotics. The release kinetics of the BMP-2 were an initial burst to recruit cells and sustained release to induce the migrating cells. The Vancomycin (Vanc) release kinetics were designed to protect the graft from contamination until vascularisation by having an initial burst and then remaining over the MIC for Staph. aueus for two months. In this study, PUR+BMP-2+Vanc scaffolds were first tested in a non-infected critical size rat femoral segmental defect and was found to perform comparably to PUR+BMP-2, thus indicating that Vanc did not hinder bone healing. PUR+BMP-2+Vanc scaffolds were subsequently evaluated in an infected critical size rat femoral segmental defect. The dual delivery approach resulted in significantly more new bone formation and infection control than both PUR+BMP-2 and the collagen+BMP-2 treatments. These data indicate that the dual-delivery strategy effectively protects the graft from infection during wound healing and regenerates more bone in contaminated defects. This moderately osteoconductive bone graft is capable of being injected, provides a more sustained release of BMP-2 than the collagen sponge, and can release antibiotics for over 8 weeks. The dual-delivery approach may improve patient outcomes of open fractures by protecting the osteoinductive graft from colonization until vascularization occurs.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXVII | Pages 19 - 19
1 Jun 2012
Yu J Li B Fairbank J Urban J
Full Access

Introduction

Elastic fibres are constructed of a central core of elastin surrounded by microfibrils that are composed mainly of fibrillin-1 and fibrillin-2. Patients with mutations in the gene encoding fibrillin-1 or fibrillin-2 develop Marfan syndrome or Beals syndrome (congenital contractural arachnodactyly), respectively. Scoliosis is one of the clinical manifestations in these patients, but how a defect in the elastic proteins could lead to a spinal deformity is not clear. On the one hand, the mutations could induce scoliosis via mechanical means as they could lead to alterations in the biomechanics of the elastic fibre system. On the other hand, elastic fibres also bind growth factors such as transforming growth factor β (TGFβ) and bone morphogenic proteins (BMPs), and the mutations could hence change patterns of spinal growth.

Methods

We have investigated the localisation of elastic proteins in different spinal tissues at different stages of curve development in mouse models and in human tissue obtained during scoliosis surgery.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_II | Pages 100 - 100
1 May 2011
Brown K Li B Guda T Guelcher S Wenke J
Full Access

Background: Despite aggressive debridement, thorough irrigation, systemic antibiotics, and staged treatment, many open fractures still become infected. A graft that can promote bone regeneration and prevent infection could decrease complications. Polyurethane (PUR) scaffolds have previously been shown in separate studies to be nontoxic, osteoconductive, can promote bone growth by delivering BMP, and prevent infection by the sustained release of an antibiotic. This scaffold can deliver both BMP and vancomycin simultaneously; the purpose of this study is to determine if the co-delivery of the antibiotic inhibits bone formation.

Methods: Using an established critical size defect rat femur model, the amount of bone formation created by PUR scaffolds containing low and high doses of rhBMP-2 (2.4 μg and 22.4 μg respectively) and 0.8 mg vancomycin (8% of graft by weight) were compared to scaffolds that contained rhBMP-2 without antibiotics. After 4 weeks, the femurs were harvested and bone growth was assessed using microCT.

Results: There was no significant difference in bone growth between the groups that had the high dose of rhBMP-2. Surprisingly, the scaffolds that had the low dose of rhBMP-2 and vancomycin promoted more bone formation than scaffolds that had rhBMP-2 and no antibiotics.

Conclusions: The addition and co-delivery of vancomycin to the scaffolds did not inhibit bone growth. The addition of vancomycin to the PUR scaffolds may have altered the release kinetics of the rhBMP-2; this may explain the increase of bone formation in this group. This study demonstrates that incorporation of a therapeutic and a clinically-relevant level of vancomycin does not inhibit bone formation. These results suggest that a dual delivery bone graft has potential to reducing complications associated with open fractures.