The computational modelling and 3D technology are finding more and more applications in the medical field. Orthopedic surgery is one of the specialties that can benefit the most from this solution. Three case reports drawn from the experience of the authors’ Orthopedic Clinic are illustraded to highlight the benefits of applying this technology. Drawing on the extensive experience gained within the authors’ Operating Unit, three cases regarding different body segments have been selected to prove the importance of 3D technology in preoperative planning and during the surgery. A sternal transplant by allograft from a cryopreserved cadaver, the realization of a custom made implant of the glenoid component in a two-stage revision of a reverse shoulder arthroplasty, and a case of revision on a hip prosthesis with acetabular bone loss (Paprosky 3B) treated with custom system. In all cases the surgery was planned using 3D processing software and models of the affected bone segments, printed by 3D printer, and based on CT scans of the patients. The surgical implant was managed with dedicated instruments. The use of 3D technology can improve the results of orthopedic surgery in many ways: by optimizing the outcomes of the operation as it allows a preliminary study of the bone loss and an evalutation of feasibility of the surgery, it improves the precision of the positioning of the implant, especially in the context of severe deformity and bone loss, and it reduces the operating time; by improving surgeon training; by increasing patient involvement in decision making and informed consent. 3D technology, by offering targeted and customized solutions, is a valid tool to obtain the tailored care that every patient needs and deserves, also providing the surgeon with an important help in cases of great complexity

An overview about 3D printing technology in orthopaedic applications will be given based on examples. The process from early prototypes to certified implants coming from serial production will be demonstrated also considering relevant surrounding conditions. Today's focus is mostly on orthopaedic implants, but there is a high potential for new implant-related surgical instrument solutions taking into account up-coming clinical demands and user needs accessible by actual 3D printing technologies

Digital Ventilated Cages (DVC) offer an innovative technology to obtain accurate movement data from a single mouse over time [1]. Thus, they could be used to determine the occurrence of a tendon damage event as well as inform on tissue regeneration [2,3]. Therefore, using the mouse model of tendon experimental damage, in this study it has been tested whether the recovery of tissue microarchitecture and of extracellular matrix (ECM) correlates with the motion data collected through this technology. Mice models were used to induce acute injury in Achilles tendons (ATs), while healthy ones were used as control. During the healing process, the mice were housed in DVC cages (Tecniplast) to monitor animal welfare and to study biomechanics assessing movement activity, an indicator of the recovery of tendon tissue functionality. After 28 days, the AT were harvested and assessed for their histological and immunohistochemical properties to obtain a total histological score (TSH) that was then correlated to the movement data. DVC cages showed the capacity to distinguish activity patterns in groups from the two different conditions. The data collected showed that the mice with access to the mouse wheel had a higher activity as compared to the blocked wheel group, which suggests that the extra movement during tendon healing improved motion ability. The histological results showed a clear difference between different analyzed groups. The bilateral free wheel group showed the best histological recovery, offering the highest TSH score, thus confirming the results of the DVC cages and the correlation between movement activity and structural recovery. Data obtained showed a correlation between TSH and the DVC cages, displaying structural and movement differences between the tested groups. This successful correlation allows the usage of DVC type cages as a non-invasive method to predict tissue regeneration and recovery. Acknowledgements: This research is part of the P4FIT project ESR13, funded by the H2020-ITN-EJD MSCA grant agreement No.955685

The COVID-19 pandemic necessitated a pivot to online learning for many traditional, hands-on subjects such as anatomy. This, coupled with the increase in online education programmes, and the reduction of time students spend in anatomy dissection rooms, has highlighted a real need for innovative and accessible learning tools. This study describes the development of a novel 3-dimensional (3D), interactive anatomy teaching tool using structured light scanning (SLS) technology. This technique allows the 3D shape and texture of an object to be captured and displayed online, where it can be viewed and manipulated in real-time. Human bones of the upper limb, vertebrae and whole skulls were digitised using SLS using Einscan Pro2X/H scanners. The resulting meshes were then post-processed to add the captured textures and to remove any extraneous information. The final models were uploaded into Sketchfab where they were orientated, lit and annotated. To gather opinion on these models as effective teaching tools, surveys were completed by anatomy students (n=35) and anatomy educators (n=8). Data was collected using a Likert scale response, as well as free text answers to gather qualitative information. 3D scans of the scapula, humerus, radius, ulna, vertebrae and skull were successfully produced by SLS. Interactive models were produced via scan data in Sketchfab and successfully annotated to provide labelled 3D models for examination. 94% of survey respondents agreed that the interactive models were easy to use (n=35, 31% agree and 63% strongly agree) and 97% agreed that the 3D interactive models were more useful than 2D images for learning bony anatomy (n=35; 26% agree and 71% strongly agree). This initial study has demonstrated a suitable proof-of-concept for SLS technology as a useful technique for producing 3D interactive online tools for learning and teaching bony anatomy. Current studies are focussed on determining the SLS accuracy and the ability of SLS to capture soft tissue/joints. We believe that this tool will be a useful technique for generating online 3D interactive models to study orthopaedic anatomy

Universities have an obligation to ensure that Intellectual Property (IP) outputs are properly captured and exploited according to various National and European guidelines. There are two main ways which University technology development can take on the road to commercialisation: 1. Licensing the technology to an existing company: A license is permission to do something the granting party (the licensor) has the right to otherwise prohibit. In the context of IP licensing, it is a grant, by the owner of the property, to another (the licensee) of the right to use the IP in question for commercial purposes; 2. Starting a new company: An important university objective is to explore and pursue opportunities for the exploitation of its intellectual property rights. For universities and its inventors, spin out companies often provide an effective means to achieve this objective. A spin out is created when the University creates a new company out of one of its existing departments, institutions or by an inventor. The decision of which path to take is critical and various elements can effect this decision such as the inventors own objectives, the market niche for the technology, the stage of technical development, the potential reward for each option and the types of support structures available. This talk will summarise the main points to consider when deciding on the most appropriate way to commercialise technologies developed in Universities

Objective. To analyze the short-term outcome after medial open-wedge high tibial osteotomy with a 3D-printing technology in early medial keen osteoarthritis and varus malalignment. Design and Method. 32 knees(28 cases) of mOWHTO (fixation with an angular-stable TomoFix implant(Synthes)) with a 3D-printing technology combined with arhtroscopy were prospectively surveyed with regard to functional outcome(Hospital for special knee score [HSS] score). Pre- and postoperative tibial bone varus angle (TBVA), mechanical medial proximal tibial angle (MPTA), and alignment were analyzed with regard to the result. Results. 32 knees were included (28 patients; mean age 46.5±9.3 years). The follow-up rate was 100% at 1.7±0.6 years (range, 1.2–3.2 years). Pre- and postoperative mechanical tibiofemoral axis were 6.8°±2°of varus and 1.2°± 3.4° of valgus, respectively. HSS score significantly improved from 46.0±18.3 preoperatively to 84±12 at one, 80±7 at two years (P<0.01). Conclusions. Medial open-wedge high tibial osteotomy with a 3D-printing technology combined with arthroscopy in medial keen osteoarthritis and varus malalignment is an accurate and good treatment option. High preoperative TBVA and appropriate corrected angle(0–3° of valgus)) was associated with better functional outcome at final follow-up

Production of porous titanium bone implants is a highly promising research and application area due to providing high osseointegration and achieving the desired mechanical properties. Production of controlled porosity in titanium implants is possible with laser powder bed fusion (L- PBF) technology. The main topics of this presentation includes the L-PBF process parameter optimization to manufacture thin walls of porous titanium structures with almost full density and good mechanical properties as well as good dimensional accuracy. Moreover, the cleaning and coating process of these structures to further increase osseointegration and then in-vitro biocompatibility will be covered

Osteoarthritis (OA) is a degenerative joint disease affecting millions worldwide. Early detection of OA and monitoring its progression is essential for effective treatment and for preventing irreversible damage. Although sensors have emerged as a promising tool for monitoring analytes in patients, their application for monitoring the state of pathology is currently restricted to specific fields (such as diabetes). In this study, we present the development of an optical sensor system for real-time monitoring of inflammation based on the measurement of nitric oxide (NO), a molecule highly produced in tissues during inflammation. Single-walled carbon nanotubes (SWCNT) were functionalized with a single-stranded DNA (ssDNA) wrapping designed using an artificial intelligence approach and tested using S-nitroso-N-acetyl penicillamine (SNAP) as a standard released-NO marker. An optical SWIR reader with LED excitation at 650 nm, 730 nm and detecting emission above 1000 nm was developed to read the fluorescence signal from the SWCNTs. Finally, the SWCNT was embedded in GelMa to prove the feasibility of monitoring the release of NO in bovine chondrocyte and osteochondral inflamed cultures (1–10 ng/ml IL1β) monitored over 48 hours. The stability of the inflammation model and NO release was indirectly validated using the Griess and DAF-FM methods. A microfabricated sensor tag was developed to explore the possibility of using ssDNA-SWCNT in an ex vivo anatomic set-up for surgical feasibility, the limit of detection, and the stability under dynamic flexion. The SWCNT sensor was sensitive to NO in both in silico and in vitro conditions during the inflammatory response from chondrocyte and osteochondral plug cultures. The fluorescence signal decreased in the inflamed group compared to control, indicating increased NO concentration. The micro-tag was suitable and stable in joints showing a readable signal at a depth of up to 6 mm under the skin. The ssDNA-SWCNT technology showed the possibility of monitoring inflammation continuously in an in vitro set-up and good stability inside the joint. However, further studies in vivo are needed to prove the possibility of monitoring disease progression and treatment efficacy in vivo. Acknowledgments: The project was co-financed by Innosuisse (grant nr. 56034.1 IP-LS)

Decreasing the bulk weight without losing the biomechanical properties of commercial pure titanium (Cp-Ti) medical implants is now possible by using Laser Powder Bed Fusion (L-PBF) technology. Gyroid lattice structures that have precious mechanical and biological advantages because of similarity to trabecular bone. The aim of the study was to design and develop L-PBF process parameter optimization for manufacturing gyroid lattice Cp-Ti structures. The cleaning process was then optimized to remove the non-melted powder from the gyroid surface without mechanical loss. Gyroid cubic designs were created with various relative densities by nTopology. L-PBF process parameter optimization was progressed using with Cp-Ti (EOS TiCP Grade2) powder in the EOS M290 machine to achieve parts that have almost full dense and dimensional accuracy. The metallography method was made for density. Dimensional accuracy at gyroid wall thicknesses was investigated between designed and manufactured via stereomicroscope, also mechanical tests were applied with real time experiment and numerical analysis (ANSYS). Mass loss and strut thickness loss were investigated for chemical etching cleaning process. Gyroid parts had 99,5% density. High dimensional accuracy was achieved during L-PBF process parameters optimization. Final L-PBF parameters gave the highest 19% elongation and 427 MPa yield strength values at tensile test. Mechanical properties of gyroid were controlled with changing relative density. A minute chemical etching provided to remove non-melted powders. Compression test results of gyroids at numerical and real-time analysis gave unrelated while deformation behaviors were compatible with each other. Gyroid Cp-Ti osteosynthesis mini plates will be produced with final L-PBF process parameters. MTT cytotoxicity test will be characterized for cell viability. Acknowledgements This project is granted by TUBITAK (120N943). Feza Korkusuz MD is a member of the Turkish Academy of Sciences (TÜBA)

Total ankle replacement (TAR) is contraindicated in patients with significant talar collapse due to AVN and in these patients total talus body prosthesis has been proposed to restore ankle joint. To date, five studies have reported implantation of a custom-made talar body in patients with severely damaged talus, showing the limit of short-term damage of tibial and calcaneal thalamic joint surfaces. Four of this kind of implants have been performed. The first two realized with “traditional” technology CAD-CAM has been performed in active patients affected by “missing talus” and now presents a survival follow-up of 15 and 17 years. For the third patient affected by massive talus AVN we designed a 3D printed porous titanium custom talar body prosthesis fixed on the calcaneum and coupled with a TAR, first acquiring high-resolution 3D CT images of the contralateral healthy talus that was “mirroring” obtaining the volume of fractured talus in order to provide the optimal fit. Then the 3D printed implant was manufactured. The fourth concern a TAR septic mobilization with high bone loss of the talus. The “two-stage” reconstruction conducted with the implant of total tibio-talo-calcaneal prosthesis “custom made” built with the same technology 3D, entirely in titanium and using the “trabecular metal” technology for the calcaneous interface. Weightbearing has progressively allowed after 6 weeks. No complications were observed. All the implants are still in place with an overall joint mobility ranging from 40° to 60°. This treatment requires high demanding technical skills and experience with TAR and foot and ankle trauma. The 15 years survival of 2 total talar prosthesis coupled to a TAR manufactured by a CAD-CAM procedure encourages consider this 3D printed custom implant as a new alternative solution for massive AVN and traumatic missing talus in active patients

Crosslinking has been already used for about 80 years to enhance the longevity of polyethylene cables. The polymer alteration has been achieved with peroxide, silane or irradiation. The medical devices industry discovered the benefit of this technology for its tribological applications like hip or knee bearings in the 2000s as crosslinking improves considerably the abrasion resistance of the material. The more current methods used are Gamma and Beta irradiation. On the basis of economical (rising prices of Cobalt), environmental (the radioactive source can not be turned off), technological (low dose rate) drawbacks for Gamma respectively low penetration for Beta irradiation we decided to investigate an alternative technology: the X-Ray irradiation, which provides a homogeneous crosslinking in a relatively short time. We analyzed the wear, mechanical, thermal, oxidative and network properties of two vitamin E doped UHMWPE: first crosslinked with E-Beam, second with X-Ray. There wasn't any significant difference between the X-Ray and the E-Beam crosslinked material

Football player's performance during competitive matches greatly depends on fitness and training. The use of GPS (Global Positioning System) has been revolutionary in the monitoring of player intensity during training. The aim of the study was to investigate the difference in training intensity between defenders, midfielders and forwards and if injury sustained was directly related to the intensity of training. GPS (Catapult Minimax GPS 10Hz) was used to collect training data for a professional British football club playing in the Championship, for the year August 2011/April 2012. Each player wore a GPS unit during each training session and the raw data was logged. The GPS calculates the player load which is a measure of intensity of training. It is a summation of instantaneous change of forward, sideway and upward accelerations. Adjustments are made for match days and injuries according to a defined set of rules. A total player load was obtained for each month and at the end of the season. The different injuries sustained throughout the year were logged for each player. This study shows that there is a difference between the intensity of training in different groups of players. The midfielders trained at the highest intensity and, in this group of professional football players, defenders sustained the most injuries GPS technology allows monitoring of player intensity during training. The data obtained will guide training and fitness coaches model training for the individual group of players. This will prepare players for official matches and eventually may help predict and prevent injuries

Biomedical imaging is essential in the diagnosis of musculoskeletal pathologies and postoperative evaluations. In this context, Cone-Beam technology-based Computed Tomography (CBCT) can make important contributions in orthopaedics. CBCT relies on divergent cone X-rays on the whole field of view and a rotating source-detector element to generate three-dimensional (3D) volumes. For the lower limb, they can allow acquisitions under real loading conditions, taking the name Weight-Bearing CBCT (WB-CBCT). Assessments at the foot, ankle, knee, and at the upper limb, can benefit from it in situations where loading is critical to understanding the interactions between anatomical structures. The present study reports 4 recent applications using WB-CBCT in an orthopaedic centre.

Patient scans by WB-CBCT were collected for examinations of the lower limb in monopodal standing position. An initial volumetric reconstruction is obtained, and the DICOM file is segmented to obtain 3D bone models. A reference frame is then established on each bone model by virtual landmark palpation or principal component analysis. Based on the variance of the model point cloud, this analysis automatically calculates longitudinal, vertical and mid-lateral axes. Using the defined references, absolute or relative orientations of the bones can be calculated in 3D.

In 19 diabetic patients, 3D reconstructed bone models of the foot under load were combined with plantar pressure measurement. Significant correlations were found between bone orientations, heights above the ground, and pressure values, revealing anatomic areas potentially prone to ulceration. In 4 patients enrolled for total ankle arthroplasty, preoperative 3D reconstructions were used for prosthetic design customization, allowing prosthesis-bone mismatch to be minimized. 20 knees with femoral ligament reconstruction were acquired with WB-CBCT and standard CT (in unloading). Bone reconstructions were used to assess congruency angle and patellar tilt and TT-TG. The values obtained show differences between loading and unloading, questioning what has been observed so far. Twenty flat feet were scanned before and after Grice surgery. WB-CBCT allowed characterization of the deformity and bone realignment after surgery, demonstrating the complexity and multi-planarity of the pathology.

These applications show how a more complete and realistic 3D geometric characterization of the of lower limb bones is now possible in loading using WB-CBCT. This allows for more accurate diagnoses, surgical planning, and postoperative evaluations, even by automatisms. Other applications are in progress.

Healthcare associated infections (HAI) pose a major threat to patients admitted to hospitals, and infection rates following orthopaedic arthroplasty surgery are as high as 4%, while the infection rates are even higher after revision surgery. 405 nm High-Intensity Narrow Spectrum (HINS) light has been proven to reduce environmental contamination in hospital isolation rooms, and there is potential to develop this technology for application in orthopaedic surgery. Cultured rat osteoblasts were exposed to 405 nm light to investigate if bactericidal doses of light could be used safely in the presence of mammalian cells. Cell viability was measured by MTT reduction and microscopy techniques, function by alkaline phosphatase activity, and proliferation by the BrdU assay. Exposures of up to a dose of 36 J/cm. 2. had no significant effect on osteoblast cell viability, whilst exposure of a variety of clinically relevant bacteria, to 36 J/cm. 2. resulted in up to 100% kill. Exposure to a higher dose of 54 J/cm. 2. significantly affected the osteoblast cell viability, indicating dose dependency. Work also demonstrated that 405 nm light exposure induces reactive oxygen species (ROS) production in both mammalian and bacterial cells, as shown by fluorescence generated from 6-carboxy-2′,7′-dichlorodihydrofluorescein diacetate dye. The mammalian cells were significantly protected from dying at 54 J/cm. 2. by catalase, which detoxifies H. 2. O. 2. Bacterial cells were significantly protected by sodium pyruvate (H. 2. O. 2. scavenger) and by a combination of free radical scavengers (sodium pyruvate, dimethyl thiourea (·OH scavenger), catalase) at 162 and 324 J/cm. 2. Thus the cytotoxic mechanism of 405 nm light in mammalian cells and bacteria is likely oxidative stress involving predominantly H. 2. O. 2. generation, with other ROS contributing to the damage. Additional work describing the potential for incorporation of this antimicrobial light within operating theatre lighting systems will also be discussed, and this, coupled with the cell viability and cytotoxicity results, suggests that 405 nm light could have great potential for continual patient safe decontamination during orthopaedic replacement surgeries and thereby reduce the incidence of infections

Preoperative planning for Total Hip Arthroplasty has been acknowledged as a vital step to facilitate a successful outcome. Templating ascertains the dimensions and positioning of the implants, minimizing both intraoperative and postoperative complications. The purpose of this study is to compare the accuracy of digital templating to acetate templating in the preoperative planning of Total Hip Arthroplasty.

Preoperative planning was performed on 40 consecutive patients (mean age = 70.5 years), undergoing Total Hip Arthroplasty. Digital templating was performed by the Hip fellow 1, using Orthoview software (Jacksonville, FL, USA) and recorded the sizes of the cup and stem for each of the 40 patients. Subsequently, the same 40 patients were templated by Hip fellow 2, with X-rays done with a lead marker of known size by the side of the femur, using, acetate templating method. Templating results were compared to the actual sizes of the implants used, as noted in operative notes. Templating scores for the acetabular cup were 40% (16/40) with digital templating and 50% (20/40) with acetate templating. The templating scores for stem were 28% (11/40) with digital templating and 90% (36/40) with acetate templating. The differences between templating and actual implant sizes were plotted in Bland–Altman plot. Acetate templating proved to be statistically, significantly more accurate than digital templating (p value= 0.0083).

Our results indicate that the traditional acetate method is solid and valid to use for preoperative planning. This method is accurate and offers a more affordable option for preoperative templating. Although the templated size is one, there is a tendency to increase cup size to use bigger heads, which is the recent National Joint Registries trend. We recommend that acetate templating should be used as the default option.

For decades, universities and research centers have been applying modeling and simulation (M&S) to problems involving health and medicine, coining the expression in silico clinical trials. However, its use is still limited to a restricted pool of specialists.

It is here proposed an easy-to-use cloud-based platform that aims to create a collaborative marketplace for M&S in orthopedics, where developers and model creators are able to capitalize on their work while protecting their intellectual property (IP), and researcher, surgeons and medical device companies can use M&S to accelerate time and to reduce costs of their research and development (R&D) processes.

Digital libraries on InSilicoTrials.com are built on collaborations among first-rate research center, model developers, software, and cloud providers (partners). Their access is provided to life science and healthcare companies, clinical centers, and research institutes (users), offering them with several solutions for the different steps of the orthopedics and medical devices R&D process. The platform is built using the Microsoft Azure cloud services, conforming to global standards of security and privacy for healthcare, ensuring that clinical data is properly managed, protected, and kept private. The environment protects the IP of partners against the downloading, copying, and changing of their M&S solutions; while providing a safe environment for users to seamlessly upload their own data, set up and run simulations, analyze results, and produce reports in conformity with regulatory requirements.

The proposed platform allows exploitation of M&S through a Software-as-a-Service delivery model. The pay-per-use pricing: 1. provide partners with a strong incentive to commercialize their high-quality M&S solutions; 2. enable users with limited budget, such as small companies, research centers and hospitals, to use advanced M&S solutions. Pricing of the M&S tools is based on specific aspects, such as particular features and computational power required, in agreement with the developing partner, and is distinct for different types of customers (i.e., academia or industry).

The first medical devices application hosted on InSilicoTrials.com is NuMRis (Numerical Magnetic Resonance Implant Safety), implemented in collaboration with the U.S. F.D.A. Center for Devices and Radiological Health, and ANSYS, Inc. The automatic tool allows the investigation of radiofrequency (RF)-induced heating of passive medical implants, such as orthopedic devices (e.g., rods and screws), pain management devices (e.g., leads), and cardiovascular devices (e.g., stents), following the ASTM F2182-19e2 Standard Test Method. NuMRis promotes the broader adoption of digital evidence in preclinical trials for RF safety analysis, supporting the device submission process and pre-market regulatory evaluation.

InSilicoTrials.com aims at defining a new collaborative framework in healthcare, engaging research centers to safely commercialize their IP, i.e., model templates, simulation tools and virtual patients, by helping clinicians and healthcare companies to significantly expedite the pre-clinical and clinical development phases, and to move across the regulatory approval and HTA processes.

Introduction. Iatrogenic proximal femur hoop-stress fracture is a recognised complication of uncemented hip arthroplasty. It has a reported incidence of two to three percent and increases patient morbidity. We describe a novel technology that predicts fracture in real-time by less than one minute. Method. Four proximal femora from red deer (Cervus elaphus), similar size to human proximal femora, were prepared to accept an uncemented hip arthroplasty femoral rasp (Finsbury Orthopaedics) and then mounted in a loading machine. The femora were fresh-frozen, defrosted and kept at room temperature in 0.9% saline swabs. The rasp was forced into each femur in repeated loading cycles every 10 seconds, in steps of 100N increasing from 200N to over 2000N until fracture, in a manner to simulate surgery. One sensor was attached to the surface of the proximal femur and one to the femoral rasp. The sensor outputs were recorded, analysed and displayed on a PC using a software algorithm to show signal energy (joules) and amplitude (decibels). The proximal femur was coated with specular marking paint to permit real-time 3-D digital image correlation (DIC) analysis. DIC is an established tool in engineering fracture analysis and utilises two spatially orientated video cameras to measure surface strain and fracture. The femur was observed by the human eye and loaded in cycles until a fracture was seen. The moment of fracture was marked in the recording timeline. DIC was used to confirm fracture. Results. All femora fractured in the anterior proximal cortex. Signals from both sensors were identical in form and differed by less than five percent in strength during loading. Both signals demonstrated significant increases in energy and amplitude shortly prior to fracture. Early during loading cycles the femoral rasp subsided and became well-fixed within the femur; this was associated with signals of 60-70dB. During later loading cycles the rasp ceased to subside in the femur and was well-fixed in a press-fit; subsequent loading caused fracture and this was preceded by a greater number of stronger signals of over 90dB. The increase occurred 1 to 3 loading cycles prior to fracture, or less than 30 seconds. DIC was used to confirm the presence of a fracture visible to the human eye. At the time of the first significant increase in signal there was no crack visible to the eye or to DIC analysis and the femoral rasp did not subside further into the femur. Conclusions. During press-fitting of an uncemented femoral rasp in a deer femur a significant change in signal characteristics occurs shortly prior to a fracture being visible to the eye and detectable by DIC analysis. The almost identical signal output from both sensors suggests that one single sensor mounted on a femoral rasp will suffice, thereby removing the need to expose more of the proximal femur during surgery. This technology may be able to predict and therefore prevent femur fracture during uncemented hip arthroplasty. Further research is necessary in animal and human cadavers to explore and validate this research

Capturing objective data of the postoperative changes in the mobility of patients is expected to generate a better understanding of the effect of postoperative treatment. Until recently, the collection of gait-related data was limited to controlled clinical environments. The emergence of accurate wearable accelerometers with sufficient runtime, however, enables the long-term measurement and extraction of mobility parameters, such as “real-world walking speed”. An interim analysis of 1967 hours of actibelt data (3D accelerometer, 100 Hz) from 5 patients (planned total 20) with a femur fracture and 5 patients (planned total 20) with a humerus fracture from a geriatric population at two different sites of the university hospital of the Ludwigs-Maximilian-University in Munich was performed. Mobility data was captured during several days of stationary treatment starting directly after surgery and during a short follow-up visit six weeks after the surgery. Preliminary results show an increase of the mean walking speed between the two visits independent of the type of fracture. Patients with a humerus fracture tended to walk faster than patients with a femur fracture during both visits. The data also reveals an unexpected low level of mobility during the stationary stay. Mobile accelerometry can be used to evaluate different postoperative mobilisation strategies and even provide near-time feedback in geriatric trauma patients.

One of the most common bacteria in orthopaedic prosthetic infections is Staphylococcus Aureus. Infection causes implant failure due to biofilm production. Biofilms are produced by bacteria once they have adhered to a surface.

Nanotopography has major effects on cell behaviour. Our research focuses on bacterial adhesion on nanofabricated materials. We hypothesise that surface nanotopography impacts the differential ability of staphylococci species to adhere via altered metabolomics and may reduce orthopaedic implant infection rate.

Bacteria were grown and growth conditions optimised. Polystyrene and titanium (Ti) nanosurfaces were studied. The polystyrene surfaces had different nanopit arrays, while the Ti surfaces expressed different nanowire structures. Adhesion analysis was performed using fluorescence imaging, quantitative PCR and bacterial percentage coverage calculations. Further substitution with ‘heavy’ labelled glucose into growth medium allowed for bacterial metabolomic analysis and identification of any up-regulated metabolites and pathways.

Our data demonstrates reduced bacterial adhesion on specific nanopit polystyrene arrays, while nanowired titanium showed increased bacterial adhesion following qPCR (P<0.05) and percentage coverage calculations (P<0.001). Further metabolomic analysis identified significantly increased intensity counts of specific metabolites (Pyruvate, Aspartate, Alanine and Carbamoyl aspartate).

Our study shows that by altering nanotopography, bacterial adhesion and therefore biofilm formation can be affected. Specific nanopatterned surfaces may reduce implant infection associated morbidity and mortality. The identification of metabolic pathways involved in adhesion may allow for a targeted approach to biofilm eradication in S. aureus. This is of significant benefit to both the patient and the surgeon, and may well extend far beyond the realms of orthopaedics.

The most common bacteria in orthopaedic prosthetic infections are Staphylococcus, namely Staphylococcus Epidermidis (SE) and Staphylococcus Aureus (SA). Infection causes implant failure due to biofilm production. Biofilms are produced by bacteria once they have adhered to a surface.

Nanotopography has major effects on cell behaviour. Our research focuses on bacterial adhesion and biofilm formation on nanofabricated materials. Bacteria studied were clinically relevant from an orthopaedic perspective, SA and SE. We hypothesise that that nanosurfaces can modulate bacterial adherence and biofilm formation and may reduce orthopaedic implant infection rate.

Isolated bacteria were grown and growth conditions optimised. Bacterial concentrations were calculated by using qPCR. Statistical analysis allowed identification of optimal biofilm growth conditions. These were refined on standard, non-nanopatterned surfaces, and then control and nanopatterned polystyrene (nanopits) and titanium plates (nanowires). Adhesion analysis was performed using fluorescence imaging and quantitative PCR.

4 bacterial strains were isolated and cultured. Growth kinetics based on 24hr cultures allowed isolation of optimal media for biofilm conditions (Dulbecco's Modified Eagle Medium with additional supplements). Highest bacterial concentrations were found following 2hrs incubation with Lysozyme during qPCR. Bacterial concentration significantly increased between 30, 60 and 90 minutes incubation. Differences in percentage coverage on different polysyrene nanosurfaces (nanopits) were noted varying. This was confirmed by qPCR extractions that showed different bacterial concentrations on different nanopatterns. Titanium nanowire surfaces significantly increased bacterial adhesion (P<0.05).

Our study cultured and quantified bacterial biofilm and suggests that by altering nanotopography, bacterial adhesion and therefore biofilm formation can be affected. Specific nanopatterned surfaces may reduce implant infection associated morbidity and mortality. Clearly this is of significant benefit to the patient, the surgeon and the NHS, and may well extend far beyond the realms of orthopaedics.