Method

This study was nested in a randomized clinical trial comparing single-dose cefazolin with prolonged prophylaxis (15 doses of cefazolin over 5 days) for revision arthroplasty of the hip or knee. For this analysis, patients were included if an unsuspected PJI (defined as ≥2 positive intraoperative tissue samples with the same microorganism) was diagnosed. PJI treatment consisted of 12 weeks of a rifampicin-based regimen in Staphylococcal PJI, without removal of the prosthesis. We examined Infection characteristics and success of treatment after one year, defined as the absence of signs or treatment for PJI during follow-up.

Patients and Method

We performed a prospective cohort study during the period from 2018 to 2022. Patients with infected bone defect of long bones were included. Management protocol consisted of two stages in all patients. The first stage consisted in debridement, tissues biopsy for microbiological culture, stabilization with external fixator and defect filling with gentamicin cement spacer. The second stage consisted of reconstruction using a cancellous bone autograft alone, or a mixture of autograft with allograft (demineralized bone matrix + tricalcium phosphate) and 1 gram of vancomycin powder. All patients were followed-up for at least one year. The results were assessed based on both objective (clinical and radiographic evaluation) and subjective (limb function and patient satisfaction) criteria. Main outcomes were bone union, reoperation and failure rates, union time, and limb function.

Method

Swiss Alpine sheep (n=8), (2–6 years, 50–80 kg) were included in this study. This study was approved by cantonal Ethical authorities in Chur, Switzerland. A 2 mm osteotomy was created in the tibia and fixed with a 10-hole 5.5 mm steel plate. Subsequently, 2.5 mL of saline solution containing 10⁶ CFU/mL of Staphylococcus aureus MSSA (ATCC 25923) was added over the plate. Sheep were observed for 2 (n=3) or 5 weeks (n=5) until revision surgery, during which visibly infected or necrotic tissues were removed, and the wound flushed with saline. All samples were collected for bacterial quantification. After revision surgery, the sheep were treated systemically for 2 weeks with flucloxacillin and for 4 weeks with rifampicin and cotrimoxazole. After 2 further weeks off antibiotics, the animals were euthanized. Bacteriological culture was performed at the end of the study. Bone cores were isolated from the osteotomy site and processed for Giemsa & Eosin and Brown and Brenn staining. A radiographical examination was performed every second week.

Method

2,256 patients that underwent aseptic rTJA at a single high-volume institution between 2016–2022 were retrospectively reviewed. Patient demographics and comorbidities were recorded to determine if they had 1 or more ‘IBC’, a long list of preoperative conditions including autoimmune diseases, active smoking, body mass index (BMI)>35, diabetes mellitus, and chronic kidney disease (CKD). Reoperation for PJI at 90-days and 1-year was recorded. Chi-squared or Fischer's exact tests were calculated to determine the association between preoperative presence/absence of IBC and PJI. Multivariable logistic regressions were conducted to determine if specific comorbidities within the IBC individually conferred an increased PJI risk.

Method

In our tertiary referral centre for orthopaedic infections, we started the outpatient monitoring of antimicrobial treatment (OMAT)- team for patients who will receive antimicrobial therapy for >2 weeks. Before discharge, our trained nurse gives instruction to the patient. Within 3 days after hospital discharge the patient is contacted by phone to, if necessary, clarify ambiguities in monitoring set up. During this contact, the nurse checks for side effects, addresses logistic problems regarding laboratory monitoring or future appointments and coaches patients for other questions. The patient is instructed how to recognize and who to contact in case of red flags and problems possibly related to the treatment. This is repeated after every laboratory check-up. Supervision is performed by an infectious disease specialist in close collaboration with the patient's surgeon.

Method

In this retrospective cohort study we identified patients who required surgery for an OM after PSI (Checketts-Otterburn Classification Grade 6) between 2011 and 2021. We investigated patient demographics, aetiology of the OM, pathogen and histology, treatment strategies and complications. Infection was confirmed using the 2018 FRI Consensus Definition. Successful outcome was defined as an infection-free interval of at least 24 months following surgery, which was defined as minimum follow-up.

Aim

To assess S. aureus vs. host cell colonization of contaminated implants vis intravital multiphoton laser scanning microscopy (IV-MLSM) in a murine model.

Methods

Overall, 206 prospectively collected periprosthetic synovial fluid samples from 169 patients (106f/63m; 38 hip/131 knee) who underwent revision surgeries were retrospectively evaluated for calprotectin concentration. The following groups were analyzed: unexpected negative cultures (UNC; 32/206), unexpected positive cultures (UPC; 28/206), and unclear cases (65/206) with conflicting clinical results. In addition, we added a true aseptic (40/206), and true septic (41/206) control groups according to the international consensus meeting (ICM) 2018 PJI classification. Calprotectin concentration was determined by a rapid quantitative LFA (n=206) (Lyfstone®, Norway), and compared to calprotectin ELISA immunoassay (171/206). For the determination of a new calprotectin cut-off value, analysis of the area under the curve (AUC) followed by Youden's J statistic were performed using the calproctectin values from clear septic and aseptic cases. Sensitivity and specificity for calprotectin were calculated. All statistical analyses were performed using IBM-SPSS® version 25 (Armonk, NY, USA).

Methods

This was a five-year follow-up study of patients who were randomized to rUKA (n = 64) or mUKA (n = 65). Patients completed the EuroQol five-dimension questionnaire (EQ-5D) preoperatively, and at three months and one, two, and five years postoperatively, which was used to calculate quality-adjusted life years (QALYs) gained. Costs for the primary and additional surgery and healthcare costs were calculated.

Methods

A retrospective review was conducted to assess the accuracy of different marker combinations for diagnosing chronic PJI. A total of 573 patients were included in the study, of which 124 knees and 122 hips had a diagnosis of chronic PJI. Complete blood count and synovial fluid analysis were collected. Recently published blood cell ratio cut-off points were applied to receiver operating characteristic curves for all markers and combinations. The area under the curve (AUC), sensitivity, specificity, and positive and negative predictive values were calculated.

Introduction

In general the life expectancy of population is improving. This is causing to increase case load of peri-prosthesis fractures after joint replacements. We present our results of peri-prosthesis fracture around hip managed by revision arthroplasty.

Methods

A retrospective analysis of 24 consecutive patients of periprosthetic hip fracture treated with a revision arthroplasty at Major Trauma Centre between February 2021 and January 2022.

Introduction

The medial meniscus is crescent shaped and it is wider posteriorly than anteriorly. It covers up to 60 % of the articular surface of medial tibial condyle and helps with the loading distribution in the medial compartment. Meniscal lesions occur in association with ACL tears in 60 % of the time. The posterior aspect of the menisco-capsular junction is known as the meniscal rampzone. If not addressed during surgery, it could lead to unfavourable results.

Objective

Incidence of ramp lesion following ACL injuries.

INTRODUCTION

In the NHS the structure of a “regular healthcare team” is no longer the case. The NHS is facing a workforce crisis where cross-covering of ward-based health professionals is at an all-time high, this includes nurses, doctors, therapists, pharmacists and clerks. Comprehensive post-operative care documentation is essential to maintain patient safety, reduce information clarification requests, delays in rehabilitation, treatment, and investigations. The value of complete surgical registry data is emerging, and in the UK this has recently become mandated, but the completeness of post-operative care documentation is not held to the same importance, and at present there is no published standard. This project summarises a 4-stage approach, including 6 audit cycles, >400 reviewed operation notes, over a 5 year period.

OBJECTIVE

To deliver a sustainable change in post operative care documentation practices through quality improvement frameworks.

Objective

There is no specific framework for the clinical management of sports related brachial plexus injuries. Necessarily, rehabilitation is based on injury presentation and clinical diagnostics but it is unclear what the underlying evidence base to inform rehabilitative management.

Methods

A systematic review of the literature was undertaken in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We applied the PEO criteria to inform our search strategy to find articles that reported the rehabilitative management of brachial plexus injuries sustained while playing contact sports. An electronic search of Medline, CINAHL, SPORTDiscus and Web of Science from inception to 3rd November 2022 was conducted. MESH terms and Boolean operators were employed. We applied an English language restriction but no other filters. Manual searches of Google Scholar and citation searching of included manuscripts were also completed. All study types were considered for inclusion provided they were published as peer-reviewed primary research articles and contained relevant information. Two investigators independently carried out the searches, screened by title, abstract and full text. Two researchers independently extracted the data from included articles. Data was cross-checked by a third researcher to ensure consistency. To assess internal validity and risk of bias, the Joanna Briggs Institute (JBI) critical appraisal tools were utilised.

BACKGROUND

Hemi-arthroplasty (HA) as a treatment for fractured neck of femur has slightly increased since 2019 and remarkably after the COVID pandemic. The main drawback of the treatment is ongoing cartilage deterioration that may require revision to THR.

OBJECTIVE

This study assessed cartilage surface damage in hip HA by reproducing anatomical motion and loading conditions in a hip simulator.

Methods

to determine the pattern of bone loss and the average defect size that corresponds to the clinically defined defect sizes of small, medium and large defects, a series of pre-operative x-rays of patients with who underwent revision TKA were retrospectively analysed. Ten tibiae sawbones were used for the experiment. To prepare the bones, the joint surface was resected the typical resection depth required during a primary TKA (10mm). Each tibia was secured distally in a metal pot with perpendicular screws to ensure rotational and axial fixation to the testing machine. Based on X-ray findings, a fine guide wire was placed 5mm below the cut joint surface in the most medial region of the plateau. Core drills (15mm, 25mm and 35mm) corresponding to small, medium and large defects were passed over the guide wire allowing to act at the centre point, before the bone defect was created. The test was carried out on a control specimen with no defect, and subsequently on a Sawbone with a small, medium or large defect. Sleeves were inserted using the published operative technique, by trained individual using standard instruments supplied by the manufacturers. Standard axial pull-out (0 – 10mm) force and torque (0 – 30°) tests were carried out, recording the force (N) vs. displacement (mm) curves.

Results

A circular defect pattern was identified across all defects, with the centre of the defect located 5mm below the medial tibial base plate, and as medial as possible. Unlike with large defects, small and medium sized defects reduced the pull-out force and torque at the bone-implant interface, however, these reductions were not statistically significant when compared to no bony defect.

Objectives

Neonatal motor development transitions from initially spontaneous to later increasingly complex voluntary movements. A delay in transitioning may indicate cerebral palsy (CP). The general movement optimality score (GMOS) evaluates infant movement variety and is used to diagnose CP, but depends on specialized physiotherapists, is time-consuming, and is subject to inter-observer differences. We hypothesised that an objective means of quantifying movements in young infants using motion tracking data may provide a more consistent early diagnosis of CP and reduce the burden on healthcare systems. This study assessed lower limb kinematic and muscle force variances during neonatal infant kicking movements, and determined that movement variances were associated with GMOS scores, and therefore CP.

Methods

Electromagnetic motion tracking data (Polhemus) was collected from neonatal infants performing kicking movements (min 50° knee extension-flexion, <2 seconds) in the supine position over 7 minutes. Tracking data from lower limb anatomical landmarks (midfoot inferior, lateral malleolus, lateral knee epicondyle, ASIS, sacrum) were applied to subject-scaled musculoskeletal models (Gait2354_simbody, OpenSim). Inverse kinematics and static optimisation were applied to estimate lower limb kinematics (knee flexion, hip flexion, hip adduction) and muscle forces (quadriceps femoris, biceps femoris) for isolated kicks. Functional principal component analysis (fPCA) was carried out to reduce kicking kinematic and muscle force waveforms to PC scores capturing ‘modes’ of variance. GMOS scores (lower scores = reduced variety of movement) were collected in parallel with motion capture by a trained operator and specialised physiotherapist. Pearson's correlations were performed to assess if the standard deviation (SD) of kinematic and muscle force waveform PC scores, representing the intra-subject variance of movement or muscle activation, were associated with the GMOS scores.

Introduction

Dislocation post THA confers a higher risk of re-dislocation (Kotwal et al, 2009). The dual mobility (DM) cup design (1974) was aimed at improving the stability by increasing the femoral head to neck ratio (Cuthbert et al., 2019) combining the ideas of low friction arthroplasty with increased jump distance associated with a big head arthroplasty.

Aims

Understand the dislocation rates, rates of aseptic loosening, infection rate and revision rates between the 2 types of constructs to provide current and up-to date evidence.

Introduction

Intra-articular distal humerus OTA type C fractures are challenging to treat. When osteosynthesis is not feasible one can choose to do a primary arthroplasty of elbow or manage non-operatively. The indications for treatment of this fracture pattern are evolving.

Objectives

We present our outcomes and complications when this cohort of patients was managed with either open reduction internal fixator (ORIF), elbow arthroplasty or non-operatively.

Objectives

Little is known about the impact of cartilage defects on knee joint biomechanics. This investigation aimed to determine the gait characteristics of patients with symptomatic articular cartilage lesions of the knee.

Methods

Gait analyses were performed at the Regional North-West Joint Preservation Centre. Anthropometric measurements were obtained, then 16 retroreflective markers representing the Plug-in-Gait biomechanical model were placed on pre-defined anatomical landmarks. Participants walked for two minutes at a self-selected speed on a treadmill on a level surface, then for 2 minutes downhill. A 15-camera motion-capture system recorded the data. Knee kinematics were exported into Matlab to calculate the average kinematics and spatiotemporal parameters per patient across 20 gait cycles. Depending on the normality of the data, paired t-tests or Wilcoxon ranked tests were performed to compare both knees (α = 0.05).

Objectives

Epiphysiodesis is a commonly used treatment for lower limb angular deformities. However, in recent years, distal tibial growth modulation using ‘eight plates’ or screws has emerged as an alternative treatment for paediatric foot and ankle disorders, such as CTEV. Our objective was to assess the efficacy of distal tibial modulation in correcting various paediatric foot and ankle disorders.

Methods

This retrospective study analysed 205 cases of paediatric foot and ankle disorders treated between 2003 and 2022, including only cases where the eight plate or screw was fixed on the anterior surface of the distal tibia. Our aim was to measure post-operative changes in dorsiflexion, the distal tibial angle, and the tibiocalcaneal angle by examining clinical records and radiology reports.

Introduction

Skeletal muscle wasting is an important clinical issue following acute traumatic injury, and can delay recovery and cause permanent functional disability particularly in the elderly. However, the fundamental mechanisms involved in trauma-induced muscle wasting remain poorly defined and therapeutic interventions are limited.

Objectives

To characterise local and systemic mediators of skeletal muscle wasting in elderly patients following acute trauma.

Background

Post operative radiographs following total joint arthroplasty are requested as part of routine follow up in many institutions. These studies have a significant cost to the local departments, in terms of financial and clinic resources, however, previous research has suggested they may not alter the course of the patients treatment. The purpose of this study was to assess the significance of elective post operative radiographs on changes in management of patients who underwent total joint arthroplasty.

Method

All patients who underwent total knee arthroplasty and total hip arthroplasty at a District General Hospital from 2019 to 2020 were included. Data was collected retrospectively from medical records and radiograph requests. Alterations to clinical management based on radiographic findings were reviewed in clinic letters.

Objectives

In relation to regenerative therapies in osteoarthritis and cartilage repair, mesenchymal stromal cells (MSCs) have immunomodulatory functions and influence macrophage behaviour. Macrophages exist as a spectrum of pro-(M1) and anti-(M2) inflammatory phenotypic subsets. In the context of cartilage repair, we investigated MSC-macrophage crosstalk, including specifically the priming of cartilage cells by macrophages to achieve a regenerative rather than fibrotic outcome.

Methods

Human monocytes were isolated from blood cones and differentiated towards M1 and M2 macrophages. Monocytes (Mo), M1 and M2 macrophages were cultured directly and indirectly (trans-well system) with human bone marrow derived MSCs. MSCs were added during M1 polarisation and separately to already induced M1 cells. Outcomes (M1/M2 markers and ligands/receptors) were evaluated using RT-qPCR and flow cytometry. Influence on chondrogenesis was assessed by applying M1 and M2 macrophage conditioned media (CM) sequentially to cartilage derived cells (recapitulating an acute injury environment). RT-qPCR was used to evaluate chondrogenic/fibrogenic gene transcription.

Introduction

Ultrasonic cutting in surgery has great potential. However, a key limitation is heat created by friction between the bone and the blade. Bone has poor thermal conductivity which hinders the dissipation of heat, causing cell death near the cut site In addition, ultrasonic vibration may create microcracks. It was hypothesised that these effects on bone would vary with the frequency and displacement of the ultrasonically powered blade. Therefore varying frequencies and displacements of the tip of the blade were studied to find the combination with fewest microcracks and lowest temperature rise at the bone-tool interface.

Aim

To explore the effect of different frequencies and tip displacements of ultrasonic cutting devices on the amount of thermal and mechanical damage.

Objectives

To compare the effectiveness of phonophoresis (PH) and conventional therapeutic ultrasound (US) on the functional and pain outcomes of patients with knee osteoarthritis.

Methods

We conducted an electronic search through PubMed, Cochrane Central Register of Clinical Trials (CENTRAL), Web of Science (WOS), and Scopus databases. We screened the retrieved articles to include only English full-text randomized controlled trials that examined the effect of phonophoresis versus conventional therapeutic ultrasound on patients with knee osteoarthritis. Two reviewers screened, extracted the data, and independently assessed the quality of the included articles.

Objectives

Stiffness is reported in 4%–16% of patients after having undergone total knee replacement (TKR). Limitation to range of motion (ROM) can limit a patient's ability to undertake activities of daily living with a knee flexion of 83^o, 93^o, and 106^o required to walk up stairs, sit on a chair, and tie one's shoelaces respectively. The treatment of stiffness after TKR remains a challenge. Many treatment options are described for treating the stiff TKR. In addition to physiotherapy the most employed of these is manipulation under anaesthesia (MUA). MUA accounts for up to 36% of readmissions following TKR. Though frequently undertaken the outcomes of MUA remain variable and unpredictable. CPM as an adjuvant therapy to MUA remains the subject of debate. Combining the use of CPM after MUA in theory adds the potential benefits of CPM to those of MUA potentially offering greater improvements in ROM. This paper reports a retrospective study comparing patients who underwent MUA with and without post-operative CPM.

Methods

Standard practice in our institution is for patients undergoing MUA for stiff TKR to receive CPM for between 12–24hours post-operatively. Owing to the COVID-19 pandemic hospital admissions were limited. During this period several MUA procedures were undertaken without subsequent inpatient CPM. We retrospectively identified two cohorts of patients treated for stiff TKR: group 1) MUA + post-operative CPM 2) Daycase MUA. All patients had undergone initial physiotherapy to try and improve their ROM prior to proceeding to MUA. In addition to patients’ demographics pre-manipulation ROM, post-MUA ROM, and ROM at final follow-up were recorded for each patient.

Objectives

Tissue repair is believed to rely on tissue-resident progenitor cell populations proliferating, migrating, and undergoing differentiation at the site of injury. During these processes, the crosstalk between mesenchymal stromal/stem cells (MSCs) and macrophages has been shown to play a pivotal role. However, the influence of extracellular matrix (ECM) remodelling in this crosstalk, remains elusive.

Methods

Human MSCs cultured on tissue culture plastic (TCP) and encased within fibrin in vitro were treated with/without TNFα and IFNγ. Human monocytes were cocultured with untreated/pretreated MSCs on TCP or within fibrin. After seven days, the conditioned media (CM) were collected. Human chondrocytes were exposed to CM in a migration assay. The impact of TGFβ was assessed by adding an inhibitor (TGFβRi). Cell activity was assessed using RT-qPCR and XL-protein-profiler-array.

BACKGROUND

Cell culture on tissue culture plastic (TCP) is widely used across biomedical research to understand the in vivo environment of a targeted biological system. However, growing evidence indicates that the characteristics of cells investigated in this way differ substantially from their characteristics in the human body. The limitations of TCP monolayer cell cultures are especially relevant for chondrocytes, the cell population responsible for producing cartilage matrix, because their zonal organization in hyaline cartilage is not preserved in a flattened monolayer assay.

OBJECTIVE

Here, we contrast the response of primary human chondrocytes to inflammatory cytokines, tumor necrosis factor-alpha and interferon-gamma, via transcriptional, translational, and histological profiling, when grown either on TCP or within a 3D cell pellet (scaffold-less). We focus on anti-apoptotic (Bcl2), pro-apoptotic (Bax, Mff, Fis1), and senescent (MMP13, MMP1, PCNA, p16, p21) markers.

Objectives

Bone marrow aspirate concentrate (BMAC), together with fibrin glue (Tisseel, Baxter, UK) and Hyaluronic acid (HA) were used as a one-step cell therapy treating patients with ankle cartilage defects in our hospital. This therapy was proven to be safe, with patients demonstrating a significant improvement 12 months post-treatment. Enriched mesenchymal stem cells (MSCs) in BMAC are suggested inducers of cartilage regeneration, however, currently there is no point-of-care assessment for BMAC quality; especially regarding the proportion of MSCs within. This study aims to characterise the cellular component of CCR-generated BMAC using a point-of-care device, and to investigate if the total nucleated cell (TNC) count and patient age are predictive of MSC concentration.

Methods

During surgery, 35ml of bone marrow aspirate (BMA) was collected from each patients’ iliac crest under anaesthesia, and BMAC was obtained via a commercial kit (Cartilage Regeneration kit, CCR, Innotec^®, UK). BMAC was then mixed with thrombin (B+T) for injection with HA and fibrinogen. In our study, donor-matched BMA, BMAC and B+T were obtained from consented patients (n=12, age 41 ± 16years) undergoing surgery with BMAC therapy. TNC, red blood cell (RBC) and platelet (PLT) counts were measured via a haematology analyser (ABX Micros ES 60, Horiba, UK), and the proportion of MSCs in BMA, BMAC and B+T were assessed via colony forming unit-fibroblast (CFU-F) assays. Significant differences data in matched donors were tested using Friedman test. All data were shown as mean ± SD.

OBJECTIVES

Application of deep learning approaches to marker trajectories and ground reaction forces (mocap data), is often hampered by small datasets. Enlarging dataset size is possible using some simple numerical approaches, although these may not be suited to preserving the physiological relevance of mocap data. We propose augmenting mocap data using a deep learning architecture called “generative adversarial networks” (GANs). We demonstrate appropriate use of GANs can capture variations of walking patterns due to subject- and task-specific conditions (mass, leg length, age, gender and walking speed), which significantly affect walking kinematics and kinetics, resulting in augmented datasets amenable to deep learning analysis approaches.

METHODS

A publicly available (https://www.nature.com/articles/s41597-019-0124-4) gait dataset (733 trials, 21 women and 25 men, 37.2 ± 13.0 years, 1.74 ± 0.09 m, 72.0 ± 11.4 kg, walking speeds ranging from 0.18 m/s to 2.04 m/s) was used as the experimental dataset. The GAN comprised three neural networks: an encoder, a decoder, and a discriminator. The encoder compressed experimental data into a fixed-length vector, while the decoder transformed the encoder's output vector and a condition vector (containing information about the subject and trial) into mocap data. The discriminator distinguished between the encoded experimental data from randomly sampled vectors of the same size. By training these networks jointly using the experimental dataset, the generator (decoder) could generate synthetic data respecting specified conditions from randomly sampled vectors. Synthetic mocap data and lower limb joint angles were generated and compared to the experimental data, by identifying the statistically significant differences across the gait cycle for a randomly selected subset of the experimental data from 5 female subjects (73 trials, aged 26–40, weighing 57–74 kg, with leg lengths between 868–931 mm, and walking speeds ranging from 0.81–1.68 m/s). By conducting these comparisons for this subset, we aimed to assess the synthetic data generated using multiple conditions.

Objectives

Ultrasound speckle tracking is a safe and non-invasive diagnostic tool to measure soft tissue deformation and strain. In orthopaedics, it could have broad application to measure how injury or surgery affects muscle, tendon or ligament biomechanics. However, its application requires custom tuning of the speckle-tracking algorithm then validation against gold-standard reference data. Implementing an experiment to acquire these data takes months and is expensive, and therefore prohibits use for new applications. Here, we present an alternative optimisation approach that automatically finds suitable machine and algorithmic settings without requiring gold-standard reference data.

Methods

The optimisation routine consisted of two steps. First, convergence of the displacement field was tested to exclude the settings that would not track the underlying tissue motion (e.g. frame rates that were too low). Second, repeatability was maximised through a surrogate optimisation scheme. All settings that could influence the strain calculation were included, ranging from acquisition settings to post-processing smoothing and filtering settings, totalling >1,000,000 combinations of settings. The optimisation criterion minimised the normalised standard deviation between strain maps of repeat measures. The optimisation approach was validated for the medial collateral ligament (MCL) with quasi-static testing on porcine joints (n=3), and dynamic testing on a cadaveric human knee (n=1, female, aged 49). Porcine joints were fully dissected except for the MCL and loaded in a material-testing machine (0 to 3% strain at 0.2 Hz), which was captured using both ultrasound (>14 repeats per specimen) and optical digital image correlation (DIC). For the human cadaveric knee (undissected), 3 repeat ultrasound acquisitions were taken at 18 different anterior/posterior positions over the MCL while the knee was extended/flexed between 0° and 90° in a knee extension rig. Simultaneous optical tracking recorded the position of the ultrasound transducer, knee kinematics and the MCL attachments (which were digitised under direct visualisation post testing). Half of the data collected was used for optimisation of the speckle tracking algorithms for the porcine and human MCLs separately, with the remaining unseen data used as a validation test set.

Objectives

Osteoarthritis (OA) is a painful and debilitating disorder of diarthroidal joints. Progressive degeneration of the cartilage extracellular matrix (ECM) together with abnormal chondrocyte characteristics occur leading to a switch to a fibroblast-like phenotype and production of mechanically-weak cartilage. Early changes to chondrocytes within human cartilage have been observed including chondrocyte swelling^[1] together with the development of thin cytoplasmic processes which increase in number and length with degeneration^[2]. Changes to chondrocyte phenotype in degenerate cartilage are associated with F-actin redistribution and stress fibres (SF) formation, leading to morphologically-dedifferentiated (fibroblast-like) chondrocytes^[3,4]. It is unclear if these processes are a consequence of ‘passive’ cell swelling into a defective ECM or an ‘active’ event driven by changes in cell metabolism resulting in alterations to cell shape. To address this, we have quantified and compared the distribution and levels of F-actin, a key cytoskeletal protein involved in the formation of cytoplasmic processes, within in situ chondrocytes in non-degenerate and mildly degenerate human cartilage.

Methods

Human femoral head cartilage was obtained from 21 patients [15 females, 6 males, average age 69.6yrs, (range 47–90yrs)] following femoral neck fracture, with Ethical Approval and patient's permission. Cartilage explants were removed from areas graded non-degenerate grade 0 (G0) or mildly degenerate grade 1 (G1) and cultured for up to 3wks in Dulbecco's Modified Eagle's Medium (DMEM) +/− 25% human serum (HS). In situ chondrocytes were stained with CMFDA (5-chloromethylfluoresceindiacetate, Cell-Tracker Green®) and phalloidin (F-actin labelling) and imaged by confocal microscopy and analysed quantitatively using ImageJ and Imaris® software.

Objectives

Spinal disorders such as back pain incur a substantial societal and economic burden. Unfortunately, there is lack of understanding and treatment of these disorders are further impeded by the inability to assess spinal forces in vivo. The aim of this project is to address this challenge by developing and testing a novel image-driven approach that will assess the forces in an individual's spine in vivo by incorporating information acquired from multimodal imaging (magnetic resonance imaging (MRI) and biplane X-rays) in a subject-specific model.

Methods

Magnetic resonance and biplane X-ray imaging are used to capture information about the anatomy, tissues, and motion of an individual's spine as they perform a range of everyday activities. This information is then utilised in a subject-specific computational model based on the finite element method to predict the forces in their spine. The project is also utilising novel machine learning algorithms and in vitro, six-axis mechanical testing on human, porcine and bovine samples to develop and test the modelling methods rigorously.

Objectives

A promising therapy for early osteoarthritis (OA) is the transplantation of human umbilical cord-derived mesenchymal stromal cells (hUC-MSCs). The synovial fluid (SF) from a pre-clinical ovine model treated with hUC-MSCs has been profiled using proteomics and bioinformatics to elucidate potential mechanisms of therapeutic effect.

Methods

Four weeks after a medial meniscus transection surgery, sheep were injected with 10⁷ hUC-MSCs in Phosphate Buffered Saline (PBS) or PBS only (n=7) and sacrificed at 12 weeks. SF was normalised for protein abundance (ProteoMiner^TM) and analysed using label-free quantitation proteomics. Bioinformatics analyses (Ingenuity Pathway Analysis (IPA) and STRING) were used to assess differentially regulated functions from the proteomic data. Human orthologues were identified for the ovine proteins using UniProt and DAVID resources and proteins that were ≥±1.3 fold differentially abundant between treatment groups, were included in the bioinformatics analyses.

Objectives

Biomechanics is an essential form of measurement in the understanding of the development and progression of osteoarthritis (OA). However, the number of participants in biomechanical studies are often small and there is limited ways to share or combine data from across institutions or studies. This is essential for applying modern machine learning methods, where large, complex datasets can be used to identify patterns in the data. Using these data-driven approaches, it could be possible to better predict the optimal interventions for patients at an early stage, potentially avoiding pain and inappropriate surgery or rehabilitation. In this project we developed a prototype database platform for combining and sharing biomechanics datasets. The database includes methods for importing and standardising data and associated variables, to create a seamless, searchable combined dataset of both healthy and knee OA biomechanics.

Methods

Data was curated through calls to members of the OATech Network+ (https://www.oatechnetwork.org/). The requirements were 3D motion capture data from previous studies that related to analysing the biomechanics of knee OA, including participants with OA at any stage of progression plus healthy controls. As a minimum we required kinematic data of the lower limbs, plus associated kinetic data (i.e. ground reaction forces). Any additional, complementary data such as EMG could also be provided. Relevant ethical approvals had to be in place that allowed re-use of the data for other research purposes. The datasets were uploaded to a University hosted cloud platform. The database platform was developed using Javascript and hosted on a Windows server, located and managed within the department.

Objectives

Obesity is prevalent with nearly one third of the world's population being classified as obese. Total knee arthroplasty (TKA) is an effective treatment option for high BMI patients achieving similar outcomes to non-obese patients. However, increased rates of aseptic loosening in patients with a high BMI have been reported. In patients with high BMI/body mass there is an increase in strain placed on the implant fixation interfaces. As such component fixation is a potential concern when performing TKA in the obese patient. To address this concern the use of extended tibial stems in cemented implants or cementless fixation have been advocated. Extend tibial stems are thought to improve implant stability reducing the micromotion between interfaces and consequently the risk of aseptic loosening. Cementless implants, once biologic fixation is achieved, effectively integrate into bone eliminating an interface. This retrospective study compared the use of extended tibial stems and cementless implants to conventional cemented implants in high BMI patients.

Methods

From a prospectively maintained database of 3239 primary Attune TKA (Depuy, Warsaw, Indiana), obese patients (body mass index (BMI) >30 kg/m²) were retrospectively reviewed. Two groups of patients 1) using a tibial stem extension [n=162] and 2) cementless fixation [n=163] were compared to 3) a control group (n=1426) with a standard tibial stem cemented implant. All operations were performed by or under the direct supervision of specialist arthroplasty surgeons. Analysis compared the groups with respect to class I, II, and III (BMI >30kg/m², >35 kg/m², >40 kg/m²) obesity. The primary outcome measures were all-cause revision, revision for aseptic loosening, and revision for tibial loosening. Kaplan-Meier survival analysis and Cox regression models were used to compare the primary outcomes between groups. Where radiographic images at greater than 3 months post-operatively were available, radiographs were examined to compare the presence of peri-implant radiolucent lines.

Objectives

This study explores the application of a novel technique to assess the footprint of ankle ligaments through a straightforward inking method. This method aims to enhance surgical technique and contribute to the development of a tissue-engineered analogue based on real anatomical morphometric data.

Methods

Cadaveric dissection of the ATFL, CFL and PTFL was performed on 12 unpaired fresh frozen ankles adhering to regulations of the Human Tissue (Scotland) Act. The ankle complex with attaching ligaments was immersed in methylene blue. Dissection of the proximal and distal entheses of each ligament was carried out to reveal the unstained ligament footprint. Images of each ligament footprint were taken, and the area, length and width of each footprint were assessed digitally.

Objectives

Spinal stiffness and flexibility terms are typically evaluated from linear regression of experimental data and are then assembled into 36-element matrices. Summarising in vitro test results in this manner is quick, computationally cheap and has the distinct advantage of outputting simple characteristic values which make it easy to compare results. However, this method disregards many important experimental features such as stiffening effects, neutral and elastic zones magnitudes, extent of asymmetry and energy dissipation (hysteresis). Alternatives to the linear least squares method include polynomials, separation of the load-displacement behaviour into the neutral and elastic zones using various deterministic methods and variations on the double sigmoid and Boltzmann curve fits. While all these methods have their advantages, none provide a comprehensive and complete characterisation of the load-displacement behaviour of spine specimens. In 1991, Panjabi demonstrated that the flexion-extension and mediolateral bending behaviour of functional spinal units could be approximated using the viscoelastic model consisting of a nonlinear spring in series with a linear Kelvin element. Nowadays viscoelastic models are mainly used to describe creep and stress relaxation, rather than for cyclic loading. The aim of this study was to conclusively prove the viscoelastic nature of spinal behaviour subject to cyclic loading. Being able to describe the behaviour of spine specimens using springs and dampers would yield characterising coefficients with recognisable physical meaning, thus providing an advantage over existing techniques.

Methods

Six porcine isolated spinal disc specimens (ISDs) were tested under position and load control. Visual inspection of the load-displacement graphs from which the principal terms of the stiffness and flexibility matrices are derived suggest that the load-displacement behaviour could be idealised by a nonlinear spring system with damping. It was hypothesised that the contributions arising from non-linear spring-like behaviour and damping could be separated for each of the principal load-displacement graphs.

Background

1. 63,284 patients presented with neck of femur fractures in England in 2020 (NHFD report 2021)2. To maximise theatre efficiency during the first wave of COVID-19, NHSE guidance recommended the use of HA for most patients requiring arthroplasty.3. The literature reports an incidence of Hemiarthroplasty dislocations of 1–15%.

Aims

1. To study the number and possible causes of dislocations in patients with Primary hemiarthroplasty for fracture neck of femur2. To compare our data with national and international data in terms of dislocation and revision rates for Hemiarthroplasty.

Objectives

The fidelity of a 3D model created using image segmentation must be precisely quantified and evaluated for the model to be trusted for use in subsequent biomechanical studies such as finite element analysis. The bones within the ankle joint vary significantly in size and shape. The purpose of this study was to test the hypothesis that the accuracy and reliability of a segmented bone geometry is independent of the particular bone being measured.

Methods

Computed tomography (CT) scan data (slice thickness 1 mm, pixel size 808±7 µm) from three anonymous patients was used for the development of the ankle geometries (consisting of the tibia, fibula, talus, calcaneus, and navicular bones) using Simpleware Scan IP software (Synopsys, Exeter, UK). Each CT scan was segmented 4 times by an inexperienced undergraduate, resulting in a total of 12 geometry assemblies. An experienced researcher segmented each scan once, and this was used as the ‘gold standard’ to quantify the accuracy. The solid bone geometries were imported into CAD software (Inventor 2023, Autodesk, CA, USA) for measurement of the surface area and volume of each bone, and the distances between bones (tibia to talus, talus to navicular, talus to calcaneus, and tibia to fibula) were carried out. The intra-class coefficient (ICC) was used to assess intra-observer reliability. Bland Altman plots were employed as a statistical measure for criteria validity (accuracy) [1].

Objective

Up to 20% of patients can remain dissatisfied following TKR. A proportion of TKRs will need early revision with aseptic loosening the most common. The ATTUNE TKR was introduced in 2011 as successor to its predicate design The PFC Sigma (DePuy Synthes, Warsaw, In). However, following reports of early failures of the tibial component there have been ongoing concerns of increased loosening rates with the ATTUNE TKR. In 2017 a redesigned tibial baseplate (S+) was introduced, which included cement pockets and an increased surface roughness to improve cement bonding. Given the concerns of early tibial loosening with the ATTUNE knee system, this study aimed to compare revision rates and those specific to aseptic loosening of the ATTUNE implant in comparison to an established predicate as well as other implant designs used in a high-volume arthroplasty centre.

Methods

The Attune TKR was introduced to our unit in December 2011. Prior to this we routinely used a predicate design with an excellent long-term track record (PFC Sigma) which remains in use. In addition, other designs were available and used as per surgeon preference. Using a prospectively maintained database, we identified 10,202 patients who underwent primary cemented TKR at our institution between 01/04/2003–31/03/2022 with a minimum of 1 year follow-up (Mean 8.4years, range 1–20years): 1) 2406 with ATTUNE TKR (of which 557 were S+) 2) 4652 with PFC TKR 3) 3154 with other cemented designs. All implants were cemented using high viscosity cement. The primary outcome measures were all-cause revision, revision for aseptic loosening, and revision for tibial loosening. Kaplan-Meier survival analysis and Cox regression models were used to compare the primary outcomes between groups. Matched cohorts were selected from the ATTUNE subsets (original and S+) and PFC groups using the nearest neighbor method for radiographic analysis. Radiographs were assessed to compare the presence of radiolucent lines in the Attune S+, standard Attune, and PFC implants.

Objectives

Total hip replacement (THR) is one of the most successful and cost-effective interventions in orthopaedic surgery. Dislocation is a debilitating complication of THR and managing an unstable THR constitutes a significant clinical challenge. Stability in THR is multifactorial and is influenced by surgical, patient and implant related factors. It is established that larger diameter femoral heads have a wider impingement-free range of movement and an increase in jump distance, both of which are relevant in reducing the risk of dislocation. However, they can generate higher frictional torque which has led to concerns related to increased wear and loosening. Furthermore, the potential for taper corrosion or trunnionosis is also a potential concern with larger femoral heads, particularly those made from cobalt-chrome. These concerns have meant there is hesitancy among surgeons to use larger sized heads. This study presents the comparison of clinical outcomes for different head sizes (28mm, 32mm and 36mm) in primary THR for 10,104 hips in a single centre.

Methods

A retrospective study of all consecutive patients who underwent primary THR at our institution between 1st April 2003 and 31st Dec 2019 was undertaken. Institutional approval for this study was obtained. Demographic and surgical data were collected. The primary outcome measures were all-cause revision, revision for dislocation, and all-cause revision excluding dislocation. Continuous descriptive statistics used means, median values, ranges, and 95% confidence intervals where appropriate. Kaplan-Meier survival curves were used to estimate time to revision. Cox proportional hazard regression analysis was used to compare revision rates between the femoral head size groups. Adjustments were made for age at surgery, gender, primary diagnosis, ASA score, articulation type, and fixation method.

Introduction

Precision health aims to develop personalised and proactive strategies for predicting, preventing, and treating complex diseases such as osteoarthritis (OA), a degenerative joint disease affecting over 300 million people worldwide. Due to OA heterogeneity, which makes developing effective treatments challenging, identifying patients at risk for accelerated disease progression is essential for efficient clinical trial design and new treatment target discovery and development.

Objectives

This study aims to create a trustworthy and interpretable precision health tool that predicts rapid knee OA progression based on baseline patient characteristics using an advanced automated machine learning (autoML) framework, “Autoprognosis 2.0”.

Objective

The preparation of host degenerate cartilage for repair typically requires cutting and/or scraping to remove the damaged tissue. This can lead to mechanical injury and cartilage cell (chondrocytes) death, potentially limiting the integration of repair material. This study evaluated cell death at the site of cutting injury and determined whether raising the osmotic pressure (hyper-osmolarity) prior to injury could be chondroprotective.

Methods

Ex vivo human femoral head cartilage was obtained from 13 patients (5 males and 8 females: 71.8 years old) with Ethical Permission and Patient consent. Cartilage wells were created using 3 or 5mm biopsy punches. Cell death at the wounded edge of the host cartilage and the edge of the extracted explants were assessed by quantifying the percentage of cell death (PCD) and measuring the width of the cell death zone at identified regions of interest (ROI) using the confocal laser scanning microscopy and image analysis software. To assess the chondroprotective effect of hyper-osmolarity, cartilage specimens were incubated in 340 or 600mOsm media, five minutes prior to injury to allow the chondrocytes to respond to the altered osmolarity. Wounded cartilage explants and cartilage wells were then cultured for a further 150 minutes following injury.

Objectives

Young patients receiving metallic bone implants after surgical resection of bone cancer require implants that last into adulthood, and ideally life-long. Porous implants with similar stiffness to bone can promote bone ingrowth and thus beneficial clinical outcomes. A mechanical remodelling stimulus, strain energy density (SED), is thought to be the primary control variable of the process of bone growth into porous implants. The sequential process of bone growth needs to be taken into account to develop an accurate and validated bone remodelling algorithm, which can be employed to improve porous implant design and achieve better clinical outcomes.

Methods

A bone remodelling algorithm was developed, incorporating the concept of bone connectivity (sequential growth of bone from existing bone) to make the algorithm more physiologically relevant. The algorithm includes adaptive elastic modulus based on apparent bone density, using a node-based model to simulate local remodelling variations while alleviating numerical checkerboard problems. Strain energy density (SED) incorporating stress and strain effects in all directions was used as the primary stimulus for bone remodelling. The simulations were developed to run in MATLAB interfacing with the commercial FEA software ABAQUS and Python. The algorithm was applied to predict bone ingrowth into a porous implant for comparison against data from a sheep model.

Objectives

The outcomes from patella fracture have remained dissatisfactory despite advances in treatment, especially from operative fixation1. Frequently, reoperation is required following open reduction and internal fixation (ORIF) of the patella due to prominent hardware since the standard technique for patella ORIF is tension band wiring (TBW) which inevitably leaves a bulky knot and irritates soft tissue given the patella's superficial position2. We performed a systematic review to determine the optimal treatment of patella fractures in the poor host.

Methods

Three databases (EMBASE/Medline, ProQuest and PubMed) and one register (Cochrane CENTRAL) were searched. 476 records were identified and duplicates removed. 88 records progressed to abstract screening and 73 were excluded. Following review of complete references, 8 studies were deemed eligible

Objectives

The aim of this work was to compare the different techniques and the different fluid permeability of the tissue following each technique through assessing the flow of radiopaque contrast agent using μCT image analysis and 3D modelling.

Methods

Donated human tali specimens (n=12) were prepared through creating a 10mm diameter chondral defect in three different regions of each talus. Each region then underwent one of three surgical techniques: 1) Fine wire drilling, 2) Nanofracture or 3) Microfracture, equidistant sites in each defect to ensure even distribution. Each region then had an addition of 0.1 ml radiopaque contrast agent (Omnipaque™ 300), imaged using a clinical μCT scanner (SCANCO Medical AG, 73.6 μm resolution). Each μCT scan was segmented using Slicer 3D software (The Slicer Community, 2023 3D Slicer (5.2.2)). The segmentation package was used to segment the bone and contrast agent regions in each different surgical site of each sample. Each defect site was created into a cylinder and the ratio of segmented pixels of contrast agent against bone.

Objective

Short-stem total hip arthroplasty (THA) aims to preserve the proximal bone stock for future revisions, so that the first revision should resemble a primary intervention rather than a revision. This study aimed to compare the clinical and radiological outcomes in revision THA after failed short stem versus after failed conventional stem THA.

Methods

This study included forty-five patients with revision THA divided into three groups (15 each); group A: revision after short stem, group B: revision after conventional cementless stem and group C revision after conventional cemented stem. The studied groups were compared regarding 31 variables including demographic data, details of the primary and revision procedures, postoperative radiological subsidence, hospital stay, time for full weight bearing (FWB), preoperative and postoperative clinical scores.

Objectives

Osteoporotic fractures tend to be more challenging than fractures in healthy bone and the efficacy of metal screw fixation decreases with decreasing bone mineral density making it more difficult for such screws to gain purchase. This leads to increased complication rates such as malunion, non-union and implant failure (1). Bioresorbable polymer devices have seen clinical success in fracture fixation and are a promising alternative for metallic devices but are rarely used in the osteoporotic population. To address this, we are developing a system that may allow osteoporotic patients to avail of bioresorbable devices (2) but it is important to establish if patients have any reservations about having a plastic resorbable device instead of a metal one. Therefore the aim of this study was to explore the acceptability of bioresorbable fracture fixation devices to people with osteoporosis.

Methods

A cross sectional descriptive study was conducted in a UK wide population using convenience sampling. An online survey comprising nine survey questions and nine demographic questions was developed in Microsoft Teams and tested for face validity in a small pilot study (n=6). Following amendments and ethical approval, the survey was distributed by the Royal Osteoporosis Society on their website and social media platforms. People were invited to take part if they lived in the UK, were over 18 years old and had been diagnosed with osteoporosis. The survey was open for three weeks in May 2023. Responses were analysed using descriptive statistics.

Background

Ultrasonic cutting of bone boasts many advantages over alternatively powered surgical instruments, including but not limited to: elimination of swarf, reduced reaction forces, increased precision in cutting and reduced adjacent soft tissue damage, reduced post-operative complications such as bleeding and bone fracture, reduced healing time, reduced intra-operative noise and ease of handling. Despite ultrasonic cutting devices being well established in oral and maxillofacial surgery, applications in orthopaedic surgery are more niche and are not as well understood. The aim of this study was to investigate the cutting speed (mm/s) and cutting forces (N) of orthopaedic surgeons using a custom-designed state of the art ultrasonic cutting tool to cut fresh human bone samples.

Methods

A setup based on the Robot Operating System (ROS) and AprilTag was designed to track and to record the real time position of the ultrasonic cutting tool in space. Synchronised load cell axial force readings of three separate orthopaedic surgeons during ultrasonic cutting were recorded. Each surgeon was asked to find a comfortable position that reflects as close as possible their clinical handling of a cutting instrument used in surgery, and to perform two cuts in each of three samples of human cortical bone. Bone samples were obtained following ethical approval from an institutional review board (ethics approval number: SR1342) and prior informed consent was obtained from all patients. Bone samples were extracted from the femoral neck region of three hip osteoarthritis patients. During cutting, surgeons were allowed a total cutting time of one minute and cutting was conducted using an ultrasonic tool with frequency of a 35kHz (35.7 µm peak to peak displacement amplitude) under constant irrigation using a MINIPULS® 3 Peristaltic pump (38 revolutions per minute) using Phosphate-Buffered Saline (PBS) at 25°C. From the recorded data, the average instantaneous cutting velocity was calculated and the maximum cutting force was identified.

Objectives

1) to recruit dogs undergoing CrCL disease/rupture surgery and obtain discarded synovial fluid (SF) and serum/plasma (ethics approval, RCVS:2017/14/Alves); 2) to quantify the biomarkers listed above in the SF and serum/plasma by enzyme linked immunosorbent assay (ELISA); 3) to assess radiographic OA at the time of surgery and correlate it with the biomarkers and clinical findings.

Methods

Abnova, Abcam and AMSBIO ELISA kits were tested using a validation protocol relating the standard curve to a dilution series of SF and serum/plasma (1× to 1/50×), with and without SF hyaluronidase treatment to evaluate linearity, specificity and optimal dilutions. Validated ELISA kits were used to measure [IL-6], glutamate [glu], [RANKL] and [OPG] in SF and serum/plasma. For each dog, CrCL disease pre-operative lameness scores were graded as: (1) mild, (2) moderate (easily visible), (3) marked (encumbered), (4) non-weightbearing lameness. Blinded OA scoring was performed on radiographs [15–60, normal-severe OA].

Objectives

There is still controversy in the literature over whether Cervical Foraminotomy or Anterior Cervical discectomy and fusion (ACDF) is best for treating cervical Radiculopathy. Numerous studies have focused on the respective complication rates of these procedures and outcome measures with a lack of due consideration to preoperative MRI findings. Proximal foraminal stenosis can theoretically be accessed via either approach. We aimed to investigate whether patient reported outcome measures (PROMs) favoured one approach over the other in patients with proximal foraminal stenosis.

Methods

A single centre retrospective review of patients undergoing either ACDF or Cervical foraminotomy over the period 2012 to 2022. VAS, Neck disability index (NDI), EQ5DL and Patient Satisfaction on a Five Point Likert scale were obtained. Patients who had both an ACDF and a Foraminotomy were excluded. Axial MRI images were analysed and the location of the worst clinically relevant disc herniation stratified as follows: Central (1), Paracentral (2) and Foraminal (3). Correlations and average PROMs were analysed in SPSS.

OBJECTIVE

Knee varus malalignment increases medial knee compartment loading and is associated with knee osteoarthritis (OA) progression and severity¹. Altered biomechanical loading and dysregulation of joint tissue biology drive OA progression, but mechanistic links between these factors are lacking. Subchondral bone structural changes are biomechanically driven, involve bone resorption, immune cell influx, angiogenesis, and sensory nerve invasion, and contribute to joint destruction and pain². We have investigated mechanisms underlying this involving RANKL and alkaline phosphatase (ALP), which reflect bone resorption and mineralisation respectively³ and the axonal guidance factor Sema3A. Sema3A is osteotropic, expressed by mechanically sensitive osteocytes, and an inhibitor of sensory nerve, blood vessel and immune cell invasion⁴. Sema3A is also differentially expressed in human OA bone⁵.HYPOTHESIS: Medial knee compartment overloading in varus knee malalignment patients causes dysregulation of bone derived Sema3A signalling directly linking joint biomechanics to pathology and pain.

METHODS

Synovial fluid obtained from 30 subjects with medial knee OA (KL grade II-IV) undergoing high tibial osteotomy surgery (HTO) was analysed by mesoscale discovery and ELISA analysis for inflammatory, neural and bone turnover markers. 11 of these patients had been previously analysed in a published patient-specific musculoskeletal model⁶ of gait estimating joint contact location, pressure, forces, and medial-lateral condyle load distribution in a published data set included in analyses. Data analysis was performed using Pearson's correlation matrices and principal component analyses. Principal Components (PCs) with eigenvalues greater than 1 were analysed.

Objectives

Osteoarthritis (OA) is a complex joint disorder characterised by the loss of extracellular matrix (ECM) leading to cartilage degeneration. Changes to cartilage cell (chondrocyte) behaviour occur including cell swelling, the development of fine cytoplasmic processes and cell clustering leading to changes in cell phenotype and development of focal areas of mechanically-weak fibrocartilaginous matrix^[1]. To study the sequence of events in more detail, we have investigated the changes to in situ chondrocytes within human cartilage which has been lightly scraped and then cultured with serum.

Methods

Human femoral heads were obtained with Ethical permission and consent from four female patients (mean age 74 yrs) undergoing hip arthroplasty following femoral neck fracture. Osteochondral explants of macroscopically-normal cartilage were cultured as a non-scraped control, or scraped gently six times with a scalpel blade and both maintained in culture for up to 2wks in Dulbecco's Modified Eagle's Medium (DMEM) with 25% human serum (HS). Explants were then labelled with CMFDA (5-chloromethylfluorescein-diacetate) and PI (propidium iodide) (10μM each) to identify the morphology of living or dead chondrocytes respectively. Explants were imaged using confocal microscopy and in situ chondrocyte morphology, volume and clustering assessed quantitatively within standardised regions of interest (ROI) using Imaris^® imaging software.

1.0 Objectives

Predictive structural models resulting in a trabecular bone topology closely resembling real bone would be a step toward 3D printing of sympathetic prosthetics. This study modifies an established trabecular bone structural adaptation approach, with the objective of achieving an improved adapted topology, specifically connectivity, compared to CT imaging studies; whilst retaining continuum level mechanical properties consistent with those reported in experimental studies. Strain driven structural adaptation models successfully identify trabecular trajectories, although tend to overpredict connectivity and skew trabecular radii distribution towards the smallest radius included in the adaptation. Radius adaptation of each trabecula is driven by a mechanostat approach with a target strain (1250 µɛ) below which radius is decreased (resorption), and above which radius is increased (apposition). Simulations include a lazy zone, in which neither resorption nor apposition takes place (1000 to 1500 µɛ); and a dead zone (<250 µɛ) in which complete resorption of trabeculae with the smallest included radius takes place. This study assesses the impact of increasing the dead zone threshold from <250 µɛ to <1000 µɛ, the lower limit of the lazy zone.

2.0 Methods

In-silico structural models with an initial connectivity (number of trabeculae connecting at each joint) of 14 were generated using a nearest neighbour approach applied to a random cloud of points. Trabeculae were modelled using circular beams whose radii were adapted in response to normal strains caused by the axial force and bending moments due to a vertical pressure of 1 MPa applied to the top of the lattice, with the bottom of the lattice fixed in the vertical direction. Lattices in which nodes are either able (rigid jointed) or unable (pin jointed) to transmit bending moments were considered. Five virtual samples of each lattice type were used, and each simulation repeated twice: with a dead zone of either <250 µɛ or <1000 µɛ.

Objectives

Acute compartment syndrome (ACS) is a progressive form of muscle ischaemia that is a surgical emergency and can have detrimental outcomes for patients if not treated optimally. The current problem is that there is no clear diagnostic threshold for ACS or guidance as to when fasciotomies should be performed. A new diagnostic method(s) is necessary to provide real-time information about the extent of muscle ischaemia in ACS. Given that lactic acid is produced by cells through anaerobic respiration, it may be possible to measure H+ ion concentration and to use this as a measure of ischaemia within muscle. Although we are familiar with the key biochemical metabolites involved in ischaemia; and the use of viability dyes in cell culture to distinguish between living or dead cells is well recognised; research has not been undertaken to correlate the biochemical and histological findings of ischaemia in skeletal muscle biopsies. Our primary aim was to investigate the potential for viability dyes to be used on live skeletal muscle biopsies (explants). Our secondary aim was to correlate the intramuscular pH readings with muscle biopsy viability.

Methods

Nine euthanised Wistar rats were used. A pH catheter was inserted into one exposed gluteus medius muscles to record real-time pH levels and muscle biopsies were taken from the contralateral gluteus medius at the start of experiment and subsequently at every 0.1 of pH unit drop. Prior to muscle biopsy, the surface of the gluteus medius was painted with a layer of 50µmol/l Brilliant blue FCF solution to facilitate biopsy orientation. A 4mm punch biopsy tool was used to take biopsies. Each muscle biopsy was placed in a base mould filled with 4% ultra-low melting point agarose. The agarose embedded tissue block was sectioned to generate 400 micron thick tissue slices with a vibratome. The tissue slices were then placed in the staining solution with Hoechst 33342, Ethidium homodimer-1 and Calcein am. The tissue slices were imaged with Zeiss LSM880 confocal microscope's Z stack function. A dead muscle control was created by adding TritonX-100 to other tissue slices. For quantitative analyses, the images were analysed in Image J using the selection tool. This permitted individual cells to be identified and the mean grey value of each channel to be defined. Using the dead control, we were able to identify the threshold value for living cells using the Calcein AM channel.

Objective

Meta-analysis of clinical trials highlights that non-operative management of degenerative knee meniscal tears is as effective as surgical management. Surgical guidelines though support arthroscopic partial meniscectomy which remains common in NHS practice. Physiotherapists are playing an increasing role in triage of such patients though it is unclear how this influences clinical management and patient outcomes.

Methods

A 1-year cohort (July 2019–June 2020) of patients presenting with MRI confirmed degenerative meniscal tears to a regional orthopaedic referral centre (3× ESP physiotherapists) was identified. Initial clinical management was obtained from medical records alongside subsequent secondary care management and routinely collected outcome scores in the following 2-years. Management options included referral for surgery, conservative (steroid injection and rehabilitation), and no active treatment. Outcome scores collected at 1- and 2-years included the Forgotten Joint Score-12 (FJS-12) questionnaire and 0–10 numerical rating scales for worst and average pain. Treatment allocation is presented as absolute and proportional figures. Change in outcomes across the cohort was evaluated with repeated measures ANOVA, with Bonferroni correction for multiple testing, and post-hoc Tukey pair-wise comparisons. As treatment decision is discrete, no direct contrast is made between outcomes of differing interventions but additional explorative outcome change over time evaluated by group. Significance was accepted at p=0.05 and effect size as per Cohen's values.

Declaration of Interest

(a) fully declare any financial or other potential conflict of interest

Objectives

The enthesis is a specialised structure at the interface between bone and tendon with gradual integration to maintain functionality and integrity. In the process of fabricating an in-vitro model of this complex structure, this study aims to investigate growth and maturation of bone, tendon and BMSC spheroids followed by 3D mini-tissue production.

Methods

Cell spheroids Spheroids of differentiated rat osteoblasts (dRObs), rat tendon fibroblasts (RTFs) and bone marrow stem cells (BMSC) were generated by culturing in 96 well U bottom cell repellent plates. With dROb spheroids previously analysed [1], RTF spheroids were examined over a duration of up to 28 days at different seeding densities 1×10⁴, 5×10⁴, 1×10⁵, 2×10⁵ in different media conditions with and without FBS (N=3). Spheroid diameter was analysed by imageJ/Fiji; Cell proliferation and viability was assessed by trypan blue staining after dissociating with accutase + type II collagenase mix; necrotic core by H&E staining; and extracellular matrix by picro-sirius red (RTFs) staining to visualise collagen fibres under bright-field and polarised light microscope.

Objectives

The syndesmosis joint, located between the tibia and fibula, is critical to maintaining the stability and function of the ankle joint. Damage to the ligaments that support this joint can lead to ankle instability, chronic pain, and a range of other debilitating conditions. Understanding the kinematics of a healthy joint is critical to better quantify the effects of instability and pathology. However, measuring this movement is challenging due to the anatomical structure of the syndesmosis joint. Biplane Video Xray (BVX) combined with Magnetic Resonance Imaging (MRI) allows direct measurement of the bones but the accuracy of this technique is unknown. The primary objective is to quantify this accuracy for measuring tibia and fibula bone poses by comparing with a gold standard implanted bead method.

Methods

Written informed consent was given by one participant who had five tantalum beads implanted into their distal tibia and three into their distal fibula from a previous study. Three-dimensional (3D) models of the tibia and fibula were segmented (Simpleware Scan IP, Synopsis) from an MRI scan (Magnetom 3T Prisma, Siemens). The beads were segmented from a previous CT and co-registered with the MRI bone models to calculate their positions. BVX (125 FPS, 1.25ms pulse width) was recorded whilst the participant performed level gait across a raised platform. The beads were tracked, and the bone position of the tibia and fibula were calculated at each frame (DSX Suite, C-Motion Inc.). The beads were digitally removed from the X-rays (MATLAB, MathWorks) allowing for blinded image-registration of the MRI models to the radiographs. The mean difference and standard deviation (STD) between bead-generated and image-registered bone poses were calculated for all degrees of freedom (DOF) for both bones.

Objectives

Osteoarthritis is a common articular cartilage disorder and causes a significant global disease burden. Articular cartilage has a limited capacity of repair and there is increasing interest in the use of cell-based therapies to facilitate repair including the use of Mesenchymal Stromal Cells (MSCs). There is some evidence in the literature that suggests that advancing age and gender is associated with declining MSC function, including reduced proliferation and differentiation potential, and greater cellular apoptosis. In our study, we first performed a systematic review of the literature to determine the effects of chronological age and gender on the in vitro properties of MSCs, and then performed a laboratory study to investigate these properties.

Methods and Results

We initially conducted a PRISMA systematic review of the literature to review the evidence base for the effects of chronological age and gender on the in vitro properties of MSCs including cell numbers, expansion, cell surface characterization and differentiation potential. This was followed by laboratory-based experiments to assess these properties. Compare the extent of the effect of age on MSC cell marker expression, proliferation and pathways. Tissue from patients undergoing total knee replacement surgery was used to isolate MSCs from the synovium, fat pad and bone fragments using a method developed in our laboratory. The growth kinetics was determined by calculating the population doublings per day. Following expansion in culture, MSCs at P2 were characterised for a panel of cell surface markers using flow cytometry. The cells were positive for CD73, CD90 and CD105, and negative for antibody cocktail (eg included CD34, CD45). The differentiation potential of the MSCs was assessed through tri-lineage differentiation assays. At P2 after extracting RNA, we investigate the gene analysis using Bulk seq. Clear differences between the younger and older patients and gender were indicated.

OBJECTIVES

To determine if force measured using a strain gauge in circular external fixation frames is different for 1) different simulated stages of bone healing, and for 2) fractures clinically deemed either united or un-united.

METHODS

In a laboratory study, 3 similar Ilizarov frame constructs were assembled using a Perspex bone analogue. Constructs were tested in 10 different clinical situations simulating different stages of bone healing including with the bone analogue intact, with 1,3 and 50mm gaps, and with 6 materials of varying stiffness's within the 50mm gap. A Bluetooth strain gauge was inserted across the simulated fracture focus, replacing one of the 4 threaded rods used to construct the frame. Constructs were loaded to 700N using an Instron testing machine and maximum force during loading was measured by the strain gauge. Testing was repeated with the strain gauge replacing each of the 4 threaded rods in turn, with measurements being repeated 3 times, across all 3 frame constructs for all 10 simulated clinical situations (n=360). Force measurements between the situations were compared using a Kruskal-Wallis test (KW) and a post-hoc Steel test was used for multiple comparison against control (intact bone model). Additionally, a pilot study has been initiated to assess clinical efficacy of the strain gauge measurement in patients with circular frames. The strain gauge replaced the anterior rod across the fracture focus for each patient. Patients were asked to step on a weighing scale with their affected limb, and maximum weight transfer through the limb and maximal force measured in the frame were recorded. This was repeated 3 times and a mean ratio of force to weight through affected limb was calculated for each patient. The clinical situation at each measurement was designated as united or un-united by one of the senior authors for analysis. Force measurements between the situations were compared using a Wilcoxon-Mann-Whitney test.

Objectives

Investigate Magnetic Resonance Imaging (MRI) as an alternative to Computerised Tomography (CT) when calculating kinematics using Biplane Video X-ray (BVX) by quantifying the accuracy of a combined MRI-BVX methodology by comparing with results from a gold-standard bead-based method.

Methods

Written informed consent was given by one participant who had four tantalum beads implanted into their distal femur and proximal tibia from a previous study. Three-dimensional (3D) models of the femur and tibia were segmented (Simpleware Scan IP, Synopsis) from an MRI scan (Magnetom 3T Prisma, Siemens). Anatomical Coordinate Systems (ACS) were applied to the bone models using automated algorithms¹. The beads were segmented from a previous CT and co-registered with the MRI bone models to calculate their positions. BVX (60 FPS, 1.25 ms pulse width) was recorded whilst the participant performed a lunge. The beads were tracked, and the ACS position of the femur and tibia were calculated at each frame (DSX Suite, C-Motion Inc.). The beads were digitally removed from the X-rays (MATLAB, MathWorks) allowing for blinded image-registration of the MRI models to the radiographs. The mean difference and standard deviation (STD) between bead-generated and image-registered bone poses were calculated for all degrees of freedom (DOF) for both bones. Using the principles defined by Grood and Suntay², 6 DOF kinematics of the tibiofemoral joint were calculated (MATLAB, MathWorks). The mean difference and STD between these two sets of kinematics were calculated.

Objectives

While spinal fusion is known to be associated with adjacent disc degeneration, little is known on the role of the facet joints in the process, and whether their altered biomechanics following fusion plays a role in further spinal degeneration. This work aimed to develop a model and method to sequentially measure the effects of spinal fusion on lumbar facet joints through synchronisation of both motion analysis, pressure mapping and mechanical analysis.

Methods

Parallel measurements of mature ovine lumbar facet joints (∼8yr old, n=3) were carried out using synchronised load and displacement measurements, motion capture during loading and pressure mapping of the joint spaces during loading. Functional units were prepared and cemented in PMMA endcaps. Displacement-controlled compression measurements were carried out using a materials testing machine (3365, Instron, USA) at 1 mm/min up to 950 N with the samples in a neutral position, while motion capture of the facet joints during compression was carried out using orthogonal HD webcams (Logitech, Switzerland) to measure the displacement of key facet joint features. The pressure mapping of load transfer during displacement was carried out using a flexible pressure sensor (6900 series, Tekscan, USA). Each sample was imaged at an isotropic resolution of 82 microns using a μCT scanner (XtremeCT, Scanco, Switzerland) to quantify the curvature within the facet joints.

Introduction

Component mal-positioning in total hip replacement (THR) and total knee replacement (TKR) can increase the risk of revision for various reasons. Compared to conventional surgery, relatively improved accuracy of implant positioning can be achieved using computer assisted technologies including navigation, patient-specific jigs, and robotic systems. However, it is not known whether application of these technologies has improved prosthesis survival in the real-world. This study aimed to compare risk of revision for all-causes following primary THR and TKR, and revision for dislocation following primary THR performed using computer assisted technologies compared to conventional technique.

Methods

We performed an observational study using National Joint Registry data. All adult patients undergoing primary THR and TKR for osteoarthritis between 01/04/2003 to 31/12/2020 were eligible. Patients who received metal-on-metal bearing THR were excluded. We generated propensity score weights, using Sturmer weight trimming, based on: age, gender, ASA grade, side, operation funding, year of surgery, approach, and fixation. Specific additional variables included position and bearing for THR and patellar resurfacing for TKR. For THR, effective sample sizes and duration of follow up for conventional versus computer-guided and robotic-assisted analyses were 9,379 and 10,600 procedures, and approximately 18 and 4 years, respectively. For TKR, effective sample sizes and durations of follow up for conventional versus computer-guided, patient-specific jigs, and robotic-assisted groups were 92,579 procedures over 18 years, 11,665 procedures over 8 years, and 644 procedures over 3 years, respectively. Outcomes were assessed using Kaplan-Meier analysis and expressed using hazard ratios (HR) and 95% confidence intervals (CI).

Objectives

The objective of this study is to investigate if genomic sequencing is a useful method to diagnose orthopaedic infections. Current methods used to identify the species of bacteria causing orthopaedic infections take considerable time and the results are frequently insufficient for guiding antibiotic treatment. The aim here is to investigate if genomic sequencing is a faster and more reliable method to identify the species of bacteria causing infections. Current methods include a combination of biochemical markers and microbiological cultures which frequently produce false positive results and false negative results.

Methods

Samples of prosthetic fluid were obtained from surgical interventions to treat orthopaedic infections. DNA is extracted from these samples lab and nanopore genomic sequencing is performed. Initial investigations informed that a sequencing time of 15 minutes was sufficient. The resulting genomic sequence data was classified using Basic Local Alignment Tool (BLAST) against the NCBI bacterial database and filtered by only including reads with an identity score of 90 and E-value of 1e-50. An E-value of 1e-50 suggests a high-quality result and is commonly used when analysing genomic data. This data was then filtered in R Studio to identify if any species were associated with orthopaedic infections. The results from genomic sequencing were compared to microbiology results from the hospital to see if the same species had been identified. The whole process from DNA extraction to output took approximately 2 hours, which was faster than parallel microbiological cultures.

Objective

A common orthopaedic pain found in a wide spectrum of individuals, from young and active to the elderly is anterior knee pain (AKP). It is a multifactorial disorder which is thought to occur through muscular imbalance, overuse, trauma, and structural malalignment. Over time, this can result in cartilage damage and subsequent chondral lesions. Whilst the current gold standard for chondral lesion detection is MRI, it is not a highly sensitive tool, with around 20% of lesions thought to be mis-diagnosed by MRI. Single-photon emission computerised tomography with conventional computer tomography (SPECT/CT) is an emerging technology, which may hold clinical value for the detection of chondral lesions. SPECT/CT may provide valuable diagnostic information for AKP patients who demonstrate absence of structural change on other imaging modalities. This review systematically assessed the value of SPECT/CT as an imaging modality for knee pain, and its ability to diagnose chondral lesions for patients who present with knee pain.

Methods

Using PRISMA guidelines, a systematic search was carried out in PubMed, Science Direct, and Web of Knowledge, CINAHL, AMED, Ovid Emcare and Embase. Inclusion criteria consisted of any English language article focusing on the diagnostic value of SPECT/CT for knee chondral lesions and knee pain. Furthermore, animal or cadaver studies, comparator technique other than SPECT/CT or patients with a pathology other than knee chondral lesions were excluded from the study. Relevant articles underwent QUADAS-2 bias assessment.

Objective

This study assesses the prevalence of major and minor discordance between hip and spine T scores using Radiofrequency Echographic Multi-spectrometry (REMS). REMS is a novel technology that uses ultrasound and radiofrequency analysis to measure bone density and bone fragility at the hip and lumbar spine. The objective was to compare the results with the existing literature on Dual-Energy X-ray Absorptiometry (DEXA) the current “gold standard” for bone densitometry. REMS and DEXA have been shown to have similar diagnostic accuracy, however, REMS has less human input when carrying out the scan, therefore the rates of discordance might be expected to be lower than for DEXA. Discordance poses a risk of misclassification of patients’ bone health status, causing diagnostic ambiguity and potentially sub-optimal management decisions. Reduction of discordance rates therefore has the potential to significantly improve treatment and patient outcomes.

Methods

Results from 1,855 patients who underwent REMS investigations between 2018 and 2022 were available. Minor discordance is defined as a difference of one World Health Organisation (WHO) diagnostic classification (Normal / Osteopenia or Osteopenia / Osteoporosis). Major discordance is defined as a difference of two WHO diagnostic classifications (Normal / Osteoporosis). The results were compared with reported DEXA discordance rates.

OBJECTIVE

Changes in subchondral bone are one of few disease characteristics to correlate with pain in OA¹. Profound neuroplasticity and nociceptor sprouting is displayed within osteoarthritic (OA) subchondral bone and is associated with pain and pathology². The cause of these neural changes remains unestablished. Correct innervation patterns are indispensable for bone growth, homeostasis, and repair. Axon guidance signalling factor, Sema3A is essential for the correct innervation patterning of bony tissues³, expressed in osteocytes⁴ and known to be downregulated in bone OA mechanical loading⁵. Bioinformatic analysis has also shown Sema3a as a differentially expressed pathway by bone in human OA patients⁶.HYPOTHESIS: Pathological mechanical load and inflammation of bone causes dysregulation of Sema3A signalling leading to perturbed sensory nerve plasticity and pain.

METHODS

Human KOLF2-C1 iPSC derived nociceptors were generated by TALEN-mediated insertion of transcription factors NGN2+Brn3A and modified chambers differentiation protocol to produce nociceptor-like cells. Nociceptor phenotype was confirmed by immunocytochemistry. Human Y201-MSC cells were embedded in 3D type-I collagen gels (0.05 × 106 cell/gel), in 48-well plates and silicone plates, were differentiated to osteocytes for 7 days before stimulation with IL-6 (5ng/ml) and soluble IL-6 receptor (sIL-6r (40ng/ml), IL6/sIL6r and mechanical load mimetic Yoda1 (5μM) or unstimulated (n=5/group) (48-well plates) or were mechanically loaded in silicone plates (5000μstrain, 10Hz, 3000 cycles) or not loaded (n=5/group). Conditioned media transfer was performed from osteocyte to nociceptor cultures assessed by continuous 24-hour phase contrast confocal microscopy. 24-hours after stimulation RNA was quantified by RT-qPCR (IL6) or RNAseq whole transcriptome analysis/DEseq2 analysis (Load). Protein release was quantified by ELISA. Normally distributed data with homogenous variances was analysed by two-tailed t test.

Objectives

The need to accurately forecast the injury burden has never been higher. With an aging, ever expanding trauma population and less than half of the beds available compared to 1990, the National Health Service (NHS) is stretched to breaking point1,2. Resultantly, we aimed to determine whether it is possible to predict the proportionality of injuries treated operatively within orthopaedic departments based on their number of Neck of Femur fracture (NOF) patients reported both in our study and the National Hip Fracture Database (NHFD).

Methods

We utilised the ORthopaedic trauma hospital outcomes - Patient operative delays (ORTHOPOD) dataset of 22,585 trauma patients across the four countries of the United Kingdom (UK) admitted to 83 hospitals between 22/08/22 – 16/10/22. This dataset had two arms: arm one was assessing the caseload and theatre capacity, arm two assessed the patient, injury and management demographics.

Objectives

The aim of this study was to develop an in vitro GAG-depleted patella model and assess the biomechanical effects following treatment with a SAP:CS self-assembling hydrogel.

Methods

Porcine patellae (4–6 month old) were harvested and subject to 0.1% (w/v) sodium dodecyl sulfate (SDS) washes to remove GAGs from the cartilage. Patellae were GAG depleted and then treated by injection with SAP (∼ 6 mM) and CS (10 mg) in Ringer's solution through a 30G needle. Native, GAG depleted and SAP:CS treated patellae were tested through static indentation testing, using 15g load, 5mm indenter over 1hr period. The degree of deformation of each group was assessed and compared (Mann-Whitney, p<0.05). Native, GAG depleted, sham (saline only) and SAP:CS treated paired patellae and femurs were additionally characterized tribologically through sequential wear testing when undergoing a walking gait profile (n=6 per group). The cartilage surfaces were assessed and compared (Mann-Whitney, p<0.05) using the ICRS scoring system, surface damage was illustrated through the application of Indian ink.

Introduction

Several studies have shown that patients over 65 years have a higher mortality with covid. Combine with inherently increased morbidity and mortality in neck of femur (NoFF) fractures, it is logical to think that this subset would be most at risk.

Aims

Investigate whether there is actual increase in direct mortality from Covid infection in NoFF patients, also investigate other contributing factors to mortality with covid positivity and compare the findings with current available literature.

Objectives

The aim of this study was to investigate whether mechanical loading induced by physical activity can reduce risk of sarcopenia in middle-aged adults.

Methods

This was a longitudinal study based on a subset of UK Biobank data consisting of 1,918 participants (902 men and 1,016 women, mean age 56 years) who had no sarcopenia at baseline (assessed between 2006 and 2010). The participants were assessed again after 6 years at follow-up, and were categorized into no sarcopenia, probable sarcopenia, or sarcopenia according to the definition and algorithm developed in 2018 by European Working Group on Sarcopenia in Older People (EWGSOP). Physical activity was assessed at a time between baseline and follow-up using 7-day acceleration data obtained from wrist worn accelerometers. Raw acceleration data were then analysed to study the mechanical loading of physical activity at different intensities (i.e. very light, light, moderate-to-vigorous). Multinominal logistic regression was employed to examine the association between the incidence of sarcopenia and physical activity loading, between baseline and follow up, controlled for other factors at baseline including age, gender, BMI, smoking status, intake of alcohol, vitamin D and calcium, history of rheumatoid arthritis, osteoarthritis, secondary osteoporosis, and type 2 diabetes.

Background

Progressive muscle ischaemia results in reduced aerobic respiration and increased anaerobic respiration, as cells attempt to survive in a hypoxic environment. Acute compartment syndrome (ACS) is a progressive form of muscle ischaemia that is a surgical emergency resulting in the production of Lactic acid by cells through anaerobic respiration. Our previous research has shown that it is possible to measure H+ ions concentration (pH) as a measure of progressive muscle ischaemia (in vivo) and hypoxia (in vitro). Our aim was to correlate intramuscular pH readings and cell viability techniques with the intramuscular concentration of key metabolic biomarkers [adenosine triphosphate (ATP), Phosphocreatine (PCr), lactate and pyruvate], to assess overall cell health in a hypoxic tissue model.

Methods

Nine euthanised Wistar rats were used in a non-circulatory model. A pH catheter was used to measure real-time pH levels from one of the exposed gluteus medius muscles, while muscle biopsies were taken from the contralateral gluteus medius at the start of the experiment and subsequently at every 0.1 of a pH unit decline. The metabolic biomarkers were extracted from the snap frozen muscle biopsies and analyzed with standard fluorimetric method. Another set of biopsies were stained with Hoechst 33342, Ethidium homodimer-1 and Calcein am and imaged with a Zeiss LSM880 confocal microscope.

Objectives

This abstract provides an update on the Open Ankle Models being developed at the University of Bath. The goal of this project is to create three fully open-source finite element (FE) ankle models, including bones, ligaments, and cartilages, appropriate musculoskeletal loading and boundary conditions, and heterogeneous material property distribution for a standardised representation of ankle biomechanics and pre-clinical ankle joint analysis.

Methods

A computed tomography (CT) scan data (pixel size of 0.815 mm, and slice thickness of 1 mm) was used to develop the 3D geometry of the bones (tibia, talus, calcaneus, fibula, and navicular). Each bone was given the properties of a heterogeneous elastic material based on the CT greyscale. The density values for each bone element were calculated using a linear empirical relation, ρ= 0.0405 + (0.000918) HU and then power law equations were utilised to get the Young's Modulus value for each bone element [1]. At the bone junction, a thickness of cartilage ranging from 0.5–1 mm, and was modelled as a linear material (E=10 MPa, ν=0.4 [2]). All ligament insertions and positions were represented by four parallel spring elements, and the ligament stiffness and material attributes were applied in accordance with the published literature [2]. The ankle model was subjected to static loading (balance standing position). Four noded tetrahedral elements were used for the discretization of bones and cartilages. All degrees of freedom were restricted at the proximal ends of the tibia and fibula. The ground reaction forces were applied at the underneath of the calcaneus bone. The interaction between the cartilages and bones was modelled using an augmented contact algorithm with a sliding elastic contact between each cartilage. A tied elastic contact was used between the cartilages and the bone. FEbio 2.1.0 (University of Utah, USA) was used to construct the open-source ankle model.

Background

Distal femoral osteotomy is an established successful procedure which can delay the progression of arthritis and the need for knee arthroplasty. The surgery, however, is complex and lengthy and consequently it is generally the preserve of highly experienced specialists and thus not widely offered. Patient specific instrumentation is known to reduce procedural complexity, time, and surgeons’ anxiety levels¹ in proximal tibial osteotomy procedures. This study evaluated a novel patient specific distal femoral osteotomy procedure (Orthoscape, Bath, UK) which aimed to use custom-made implants and instrumentation to provide a precision correction while also simplifying the procedure so that more surgeons would be comfortable offering the procedure.

Presenting problem

Three patients (n=3) with early-stage knee arthritis presented with valgus malalignment, the source of which was predominantly located within the distal femur, rather than intraarticular. Using conventional techniques and instrumentation, distal femoral knee osteotomy cases typically require 1.5–2 hours surgery time. The use of bi-planar osteotomy cuts have been shown to improve intraoperative stability as well as bone healing times². This normally also increases surgical complexity; however, multiple cutting slots can be easily incorporated into patient specific instrumentation.

Methods

UK paediatric spine clinics will recruit 780 participants aged ten to 15 years-old with AIS, Risser stage 0, 1, or 2, and curve size (Cobb angle) 20° to 40° with apex at or below T7. Patients are randomly allocated 1:1, to either full-time or night-time bracing. A qualitative sub-study will explore communication and experiences of families in terms of bracing and research. Patient and Public Involvement & Engagement informed study design and will assist with aspects of trial delivery and dissemination.

Methods

Patients with idiopathic CTEV were seen in their local hospitals (‘Spokes’) for initial diagnosis and casting, followed by referral to the tertiary hospital (‘Hub’) for tenotomy. Non-idiopathic CTEV was managed solely by the Hub. Primary and secondary outcomes were achieving primary correction, and complication rates resulting in early transfer to the Hub, respectively. Consecutive data were prospectively collected and compared between patients allocated to Hub or Spokes. Mann-Whitney U test, Wilcoxon signed-rank test, or chi-squared tests were used for analysis (alpha-priori = 0.05, two-tailed significance).

Methods

There were 404 arthroplasty simulations with fluorescent gel, in which SHS was used (H+) or not (H-), and GGI was sealed (S+) or not (S-), divided into four groups: H+S+, H+S-, H-S+, and H-S-, varying by exposure duration (15 to 60 minutes) and frequency of glove exchanges (0 to 6 times). The intensity of fluorescent leakage through GGI was quantified automatically with an image analysis software. The effect of the above factors on fluorescent leakage via GGI were compared and analyzed.

Methods

A retrospective review of consecutive MoM hip arthroplasties (MoM-HRAs) using Birmingham Hip Resurfacing was conducted. Data on procedure side, indication, implant sizes and orientation, highest blood cobalt and chromium ion concentrations, and all-cause revision were collected from local and UK National Joint Registry records.

Methods

A prospective database of all patients with TGCT surgically managed by two orthopaedic oncology surgeons was reviewed. All cases irrespective of previous treatment were included and patients without follow-up were excluded. Pertinent tumour characteristics and surgical outcomes were collected for analysis.

Method

Stabilized hypochlorous acid has been reported to have a rapid kill rate on all pathogens, including MDR pathogens associated with chronic and acute wound infections. It destroys biofilm on contact, is not cytotoxic, reduces inflammation and stimulates wound healing. 0,038% of Hypochlorous acid was used as prophylaxis against infection and to treat PJI.

We report on our experience with hypochlorous acid as a wound irrigation as prophylaxis against infection (more than 600 cases) and for PJI. We also report on a University study where a head to head analysis was done on the anti-biofilm efficacy between hypochlorous acid 0,038% (Trifectiv Surgical Wound Irrigation) and Product X (an industry-standard product for the prevention and treatment of biofilm infection.

Hypochlorous acid offers a valuable addition to the armamentarium of wound antiseptics, with added anti-inflammatory value. An in vitro study demonstrated superior efficacy against biofilm when compared to Product X.

Method

Triggered by the fire that engulfed part of the hospital, we found ourself refuged at the sister tertiary hospital with no access to theatre time. We visited districts hospitals within the cluster and discovered state of the art facility underutilized. We presented a plan to establish a satellite arthroplasty center which was greatly embraced by the management. We partnered with the trade to setup an arthroplasty service in this district hospital. Employed 3 retired nurses and 2 parttime anaesthetist all on yearly contract. We developed pathways for patient selection according to American Society of Anaesthesiologist(ASA).

232 total joint arthroplasties were performed in 15-month, 33%Hips and 67%Knees. The average hospital stay was 2,3± 2days. We had 1 mortality(# NOF) and 2 cases of PJI treated successfully with debridement antibiotic and implant retention. We had 5 cases of intraoperative calcar femur fracture managed with cables and all stable at 6weeksand 3month. Over 76% of the cases were performed by fellows as the primary surgeons.

Primary hip and knee total joint replacement can be safely performed in a district hospital. Employing motivated retired staff was key to the success of this project. Fellowship trainees performed most of the operations. We suggest that other academic hospitals with long waiting list can look at emulating this model within their district.