RADCAM-A radiation camera system combining foil bolometers, AXUV diodes, and filtered soft x-ray diodes.

Measurements of radiated power are critical for characterizing and optimizing tokamak performance. The RADCAM system, comprising arrays of foil bolometers, Absolute eXtreme UltraViolet (AXUV), and filtered soft x-ray diodes, has been constructed to provide improved measurements of plasma radiation on "Tokamak a Configuration Variable" (TCV). An overview of the physical geometry, electronics, and design of the system is provided. The construction of the bolometer foils together with the improved sensitivity characteristics resulting from the inclusion of an anti-reflection carbon coating are presented. The large number of lines of sight in RADCAM are shown to significantly increase the spatial resolution over the legacy system. The system calibration procedure is detailed, and the mean system sensitivity is shown to vary by less than 5% over 1000 discharges. Additionally, the methodology for cross-calibration of the AXUV diodes with the bolometer foils is presented and applied to generate high temporal resolution measurements. The RADCAM radiation camera system is a compact, versatile system that is demonstrated to provide high resolution profiles of the radiated power in TCV.

Gas puff imaging on the TCV tokamak.

We present the design and operation of a suite of Gas Puff Imaging (GPI) diagnostic systems installed on the Tokamak à Configuration Variable (TCV) for the study of turbulence in the plasma edge and Scrape-Off-Layer (SOL). These systems provide the unique ability to simultaneously collect poloidal 2D images of plasma dynamics at the outboard midplane, around the X-point, in both the High-Field Side (HFS) and Low-Field Side (LFS) SOL, and in the divertor region. We describe and characterize an innovative control system for deuterium and helium gas injection, which is becoming the default standard for the other gas injections at TCV. Extensive pre-design studies and the different detection systems are presented, including an array of avalanche photodiodes and a high-speed CMOS camera. First results with spatial and time resolutions of up to ≈2 mm and 0.5 µs, respectively, are described, and future upgrades of the GPI diagnostics for TCV are discussed.

Implementation of high-resolution spectroscopy for ion (and electron) temperature measurements of the divertor plasma in the Tokamak à configuration variable.

High resolution spectroscopy on the Tokamak à Configuration Variable (TCV) divertor plasma provided Doppler broadening measurements to infer the ion and neutral temperature of injected helium gas. This paper presents the Divertor Spectroscopy System's (DSS) access to He II ion temperature measurements over a broad range, ≈0.5-15 eV, with an uncertainty of <10% for most of the studied plasma discharges. TCV's shaping flexibility was employed to validate these measurements against Thomson scattering across the DSS lines of sight. In detachment-related experiments, Ti(He II) ≃ Te, making this diagnostic a reliable thermometer along the divertor leg plasma over the wide range of magnetic equilibria and divertor configurations achievable in TCV. A detailed description of the diagnostic hardware, data analysis, and sources of uncertainty is presented.

Subtalar arthrodesis using a single compression screw: a comparison of results between anterograde and retrograde screwing.

INTRODUCTION: The primary objective of this study was to compare the radiological and clinical results of anterograde and retrograde screwing in subtalar arthrodesis using a single compression screw. The secondary objective was to evaluate the subjective results and consolidation of this procedure. The hypotheses were that isolated screw fixation was sufficient to achieve good consolidation and that there was no difference between the two techniques with a similar rate of bone fusion. METHODS: This is a monocentric, retrospective, radio-clinical study based on 99 patients (101 feet), 58 males and 41 females, with an average age of 64 years. The main aetiology was post-traumatic osteoarthritis, which represented 51% of cases. Two groups were formed: group A (52 feet) consisting of fixed arthrodesis with ascending (retrograde) screwing and group D (49 feet) consisting of fixed arthrodesis with descending (anterograde) screwing. The two groups were statistically comparable in terms of demographic data as well as aetiologies and comorbidities. Arthrodeses which were not fused at 6 months were reassessed at one year and in the event of any radio-clinical doubt regarding consolidation, an additional CT scan was prescribed. Average post-operative follow-up was 11 ± 5 years (2-27 years). RESULTS: Ninety-two arthrodeses (93%) were fused at one year and 9 were considered to be in non-union, 5 (9.8%) in group A, and 4 (8.3%) in group D. We recorded 30 complications, 22 of which were due to a conflict with the screw head, 18 (34.5%) in group A and 4 (8.3%) in group D (p = 0.03). Conflict between the screw head and the heel led to the removal of the screw after consolidation of the arthrodesis. The clinical results were evaluated using Odom's criteria. Nine per cent of patients described their results as excellent, 29% as good, 51% as satisfactory and 11% found the result to be poor. CONCLUSION: The fusion rate for isolated compression screw arthrodesis is good, and there is no difference between anterograde and retrograde screws. However, the discomfort caused by the screw head being insufficiently embedded in the retrograde group led to a non-negligible number of additional surgeries to remove the screw.

Comparison of knee extensor strength after anterior cruciate ligament reconstruction using either quadriceps tendon or hamstring tendon autografts.

PURPOSE: The aim was to assess the consequences of quadriceps tendon (QT) harvest on knee extensor strength after anterior cruciate ligament reconstruction (ACL-R) compared to hamstring tendon (HT) autograft. Secondary objectives were to evaluate flexor strength recovery and search for correlation between strength status and functional outcome. METHODS: This a retrospective cohort of 44 patients who underwent ACL-R using either QT (25) or HT (19). Median age was 31.1 years. We assessed thigh muscle strength thanks to concentric iso kinetic evaluation (peak torque) at 60°.s-1, 180°.s-1, 240°.s-1 and eccentric at 30°.s-1, 7 months on average after surgery. Muscle strength values were compared to the uninjured leg in order to calculate a percentage of deficit as well as unilateral hamstring/quadriceps (H/Q) ratios. KOOS score was obtained at a mean follow-up of 18 months. RESULTS: Extensor strength deficit (concentric 60°.s-1) was one average 33.1% in the QT group and 28.2% in the HT group (p = 0.42). Difference of flexor strength deficit (concentric 60°.s-1) was close to be significant with 5% and 12% of deficit in the QT and HT group, respectively (p = 0.1), and statistically significant for high angular velocity (14% versus 3% at 240°.s-1, p = 0.04). H/Q ratios were comparable in both groups ranging from 0.62 to 0.78. Quadriceps muscle strength deficit was negatively correlated with the KOOS score (Pearson coefficient = -0.4; p = 0.005). CONCLUSION: QT autograft harvest does not yield significant quadriceps muscle weakness after ACL-R, which appear to be a pejorative factor for functional outcome. LEVEL OF EVIDENCE: IV, Retrospective study.

Development of an 11-channel multi wavelength imaging diagnostic for divertor plasmas in MAST Upgrade.

Divertor detachment and alternative divertor magnetic geometries are predicted to be promising approaches to handle the power exhaust of future fusion devices. In order to understand the detachment process caused by volumetric losses in alternative divertor magnetic geometries, a Multi-Wavelength Imaging (MWI) diagnostic has recently been designed and built for the Mega Amp Spherical Tokamak Upgrade. The MWI diagnostic will simultaneously capture 11 spectrally filtered images of the visible light emitted from divertor plasmas and provide crucial knowledge for the interpretation of observations and modeling efforts. This paper presents the optical design, mechanical design, hardware, and test results of an 11-channel MWI system with a field of view of 40°. The optical design shows better than 5 mm FWHM spatial resolution at the plasma on all 11 channels across the whole field of view. The spread of angle of incidence on the surface of each filter is also analyzed to inform the bandwidth specification of the interference filters. The results of the initial laboratory tests demonstrate that a spatial resolution of better than 5 mm FWHM is achieved for all 11 channels, meeting the specifications required for accurate tomography.

Real-time feedback control of the impurity emission front in tokamak divertor plasmas.

In magnetic confinement thermonuclear fusion the exhaust of heat and particles from the core remains a major challenge. Heat and particles leaving the core are transported via open magnetic field lines to a region of the reactor wall, called the divertor. Unabated, the heat and particle fluxes may become intolerable and damage the divertor. Controlled 'plasma detachment', a regime characterized by both a large reduction in plasma pressure and temperature at the divertor target, is required to reduce fluxes onto the divertor. Here we report a systematic approach towards achieving this critical need through feedback control of impurity emission front locations and its experimental demonstration. Our approach comprises a combination of real-time plasma diagnostic utilization, dynamic characterization of the plasma in proximity to the divertor, and efficient, reliable offline feedback controller design.

Are Schatzker and AO classifications accurate enough to classify tibial plateau fractures in alpine skiers?

PURPOSE: The aims of this study were (1) to collect prospectively all tibial plateau fractures admitted to our department, over two ski seasons, and to classify them according to the Schatzker and AO classifications; (2) to assess if these classifications are accurate enough to include all types of fractures; and (3) to compare theses fractures with the series found in the literature, which included very few or no skiing accidents. METHODS: During the 2016-2017 and 2017-2018 ski seasons, we prospectively included 116 tibial plateau fractures caused by downhill skiing accidents. All patients underwent standard X-rays and 2D and 3D CT scans. The fractures were classified according to the AO and Schatzker revisited classifications. RESULTS: The full series consisted of 56 males (48%) and 60 females (52%), aged 49 ± 16 years (18-77). There were 60 type B (52%) and 56 type C fractures (48%) for AO classification and 45.5% types I, II and III and 54.5% types IV, V and VI for Schatzker classification. Thirty-five frontal fractures (30%) were not differentiated under the AO classification and, likewise, associated tibial spine fractures (28.5%) were not differentiated in the Schatzker classification. We were also unable to classify anterior tibial tuberosity fractures (14.5%) and fibula head fractures (8%). The anatomo-pathological types were not so different from road traffic accidents. CONCLUSION: Contrary to our hypothesis, the anatomical-pathological damage in tibial plateau fractures resulting from downhill skiing accidents was barely any different from those found in road traffic accidents. However, despite progress in classifications with the emergence of 3D CT scans, it is still not always possible to categorise all fractures within a given classification.

Recent and historical pollution legacy in high altitude Lake Marboré (Central Pyrenees): A record of mining and smelting since pre-Roman times in the Iberian Peninsula.

We have analyzed potential harmful trace elements (PHTE; Pb, Hg, Zn, As and Cu) on sediment cores retrieved from lake Marboré (LM) (2612 m a.s.l, 42°41'N; 0° 2'E). PHTE variability allowed us to reconstruct the timing and magnitude of trace metal pollutants fluxes over the last 3000 years in the Central Pyrenees. A statistical treatment of the dataset (PCA) enabled us to discern the depositional processes of PHTE, that reach the lake via direct atmospheric deposition. Indeed, the location of LM above the atmospheric boundary layer makes this lake an exceptional site to record the long-range transport of atmospheric pollutants in the free troposphere. Air masses back-trajectories analyses enabled us to understand the transport pathways of atmospheric pollutants while lead isotopic analyses contributed to evaluate the source areas of metal pollution in SW Europe during the Late Holocene. PHTE variability, shows a clear agreement with the main exploitation phases of metal resources in Southern Europe during the Pre-Industrial Period. We observed an abrupt lead enrichment from 20 to 375 yrs CE mostly associated to silver and lead mining and smelting practices in Southern Iberia during the Roman Empire. This geochemical data suggests that regional atmospheric metal pollution during the Roman times rivalled the Industrial Period. PHTE also increased during the High and Late Middle Ages (10-15th centuries) associated to a reactivation of mining and metallurgy activities in high altitude Pyrenean mining sites during climate amelioration phases. Atmospheric mercury deposition in the Lake Marboré record mostly reflects global emissions, particularly from Almadén mines (central Spain) and slightly fluctuates during the last three millennia with a significant increase during the last five centuries. Our findings reveal a strong mining-related pollution legacy in alpine lakes and watersheds that needs to be considered in management plans for mountain ecosystems as global warming and human pressure effects may contribute to their future degradation.

Effects of feeding a quebracho-chestnut tannin extract on lactating cow performance and nitrogen utilization efficiency.

The effects of feeding a quebracho-chestnut tannin extract mixture on performance and nitrogen (N) utilization were assessed with 36 multiparous lactating Holstein cows (mean ± standard deviation; 706 ± 59 kg of body weight; 126 ± 20 d in milk) randomly assigned to 3 dietary treatments in a randomized complete block design. Following a 2-wk covariate adjustment period, cows were fed their assigned treatment diets for 13 wk. Rice hulls were removed from a total mixed ration with a 54:46 forage:concentrate ratio (% of dry matter; DM), and a tannin extract mixture from quebracho and chestnut trees (2:1 ratio) was included at 0, 0.45, and 1.80% of dietary DM. There was no interaction between dietary treatments and experimental week for the reported measurements except milk lactose percentage. Overall, treatments did not affect milk yield (48.6 ± 7.8 kg/d), fat- and protein-corrected milk (46.1 ± 7.6 kg/d), milk fat content (3.88 ± 0.65%) and yield (1.85 ± 0.38 kg/d), and true protein yield (1.45 ± 0.21 kg/d). However, incremental levels of tannin extracts in the diet produced a linear increase in DM intake (29.2 to 30.9 kg/d) and a linear decrease in kilograms of milk per kilogram of DM intake (1.67 to 1.57 kg/kg) and MUN (12.2 to 10.8 mg/dL). Furthermore, there was a quadratic effect of tannin extracts on milk true protein content (2.96, 3.13, and 3.00% for 0, 0.45, and 1.80% tannin extract, respectively) and a tendency for linear and quadratic response for body weight gain (0.31, 0.16, and 0.44 kg/d for 0, 0.45, and 1.80% tannin, respectively). Intake of N increased linearly (782, 795, and 820 g/d) and N utilization efficiency (milk N/intake N) decreased linearly (0.300, 0.301, and 0.275 for 0, 0.45, and 1.80% tannin, respectively). Relative to the 0% diet, 1.80% tannin extract reduced estimated urinary N excretion by 11%. In this study, adding 0.45% tannin extract to the diet reduced feed efficiency but had a positive effect on milk protein content. Feeding a tannin extract mixture from quebracho and chestnut may reduce environmental labile urinary N excretion without affecting milk yield but at the expense of a lower feed utilization efficiency.

Posterior cruciate ligament reconstruction for chronic lesions: clinical experience with hamstring versus ligament advanced reinforcement system as graft.

PURPOSE: The aim of this study was to compare clinical and laximetric results in chronic, isolated posterior cruciate ligament (PCL) rupture repairs, using either a hamstring graft or an artificial ligament (ligament advanced reinforcement system (LARS®)). METHODS: Sixteen patients presenting with an isolated unilateral PCL rupture were included in this retrospective study. Initially, eight underwent a PCL reconstruction using a hamstring tendon autograft (hamstring group), and over a later period, eight further patients underwent a reconstruction using an artificial ligament with a new procedure. RESULTS: Fifteen patients were male and one female, with an average age of 29.3 years. All patients were operated on within an average time of 18 months post-injury. Pre-operative posterior laxity was equivalent (p = 0.309), 18.25 mm on average for the hamstring group and 18.75 mm for the LARS group. With an average follow-up of 24 months, residual posterior laxity was significantly improved, decreasing from 18.25 to 7.37 mm for the hamstring group (p < 0.05) with a median at 7.5 mm and from 18.75 to 5.25 mm for the LARS group (p < 0.05) with a median at 5 mm. The improvement in laxity for the hamstring group was 60% and 71.5% for the LARS group. The LARS group compares favourably (p = 0.003 and 0.01). Tegner activity level improved significantly following ligamentoplasty, with no difference between the two groups (p = 0.4). Likewise, there was no significant difference in the Lysholm and IKDC scores between the two groups (p = 0.4). CONCLUSION: The initial hypothesis of this study was proven correct. Nevertheless, a longer term study is necessary to assess the consequences of residual laxity in hamstring grafts and the long-term behaviour and tolerance of the LARS artificial ligament.

Independent clinical appraisal of the Tape Locking Screw (TLS®) anterior cruciate ligament reconstruction technique compared with the hamstring graft technique with a minimum of 12-month follow-up.

INTRODUCTION: The aim of this study was to assess the differential laxity after reconstruction of the anterior cruciate ligament (ACL) by the TLS® technique using a single tendon, the semitendinosus in four-strand graft, compared with the hamstring technique which uses both the gracilis and semitendinosus. We hypothesised that this surgical technique would provide post-surgical differential laxity measurements at least as good as those of the hamstring technique. MATERIALS AND METHODS: We carried out a prospective monocentric study on patients undergoing unilateral anterior cruciate ligament repair between December 2014 and June 2016. All patients were followed up for at least 12 months. The series compares 61 patients operated on using the TLS® technique by the same surgeon, with 33 patients operated on using the hamstring technique by a second surgeon. The main objective of the study was to compare the post-operative differential laxity, measured using the KT1000, between the two techniques. RESULTS: There was no significant difference in the patients' epidemiological characteristics and pre-operative scores between the two groups. Average pre-operative differential laxity was 6.5 mm ± 2.1 (min 3; max 12) in the TLS group and 6.4 mm ± 2.0 (min 0; max 11) in the hamstring group, with no statistically significant difference. The average post-operative difference in laxity was - 0.1 mm ± 1.9 (min - 5; max 4) in the TLS group and 0.3 mm ± 2.0 (min - 7; max 5) in the hamstring group. Again, no significant difference was observed between groups. DISCUSSION: This study demonstrates a level of post-operative differential laxity control using TLS comparable with that of the ACL reconstruction technique using a hamstring graft with preserved tibial insertion. LEVEL OF EVIDENCE: II, prospective cohort study.

MANTIS: A real-time quantitative multispectral imaging system for fusion plasmas.

This work presents a novel, real-time capable, 10-channel Multispectral Advanced Narrowband Tokamak Imaging System installed on the TCV tokamak, MANTIS. Software and hardware requirements are presented together with the complete system architecture. The image quality of the system is assessed with emphasis on effects resulting from the narrowband interference filters. Some filters are found to create internal reflection images that are correlated with the filters' reflection coefficient. This was measured for selected filters where significant absorption (up to 65% within ∼70 nm of the filter center) was measured. The majority of this was attributed to the filter's design, and several filters' performance is compared. Tailored real-time algorithms exploiting the system's capabilities are presented together with benchmarks comparing polling and event based synchronization. The real-time performance is demonstrated with a density ramp discharge performed on TCV. The behavior of spectral lines' emission from different plasma species and their interpretation are qualitatively described.

The multi-spectral imaging diagnostic.

The Multi-Spectral Imaging system is a new diagnostic that captures simultaneous spectrally filtered images from a common line of sight while maintaining a large étendue and high throughput. Imaging several atomic line intensities simultaneously may enable numerous measurement techniques. By making a novel modification of a polychromator layout, the MSI sequentially filters and focuses images onto commercial CMOS cameras while exhibiting minimal vignetting and aberrations. A four-wavelength system was initially installed and tested on Alcator C-Mod and subsequently moved to TCV. The images are absolutely calibrated and spatially registered enabling 2D mappings of atomic line ratios and absolute line intensities. The spectral transmission of the optical system was calibrated using an integrating sphere of known radiance. The images are inverted by cross-referencing points on TCV with a computer-aided design (CAD) model.

Navigation for lower limb alignment during internal fixation of complex tibial-plateau fractures.

In complex fractures of the proximal tibial metaphysis and epiphysis, possible adverse outcomes after internal fixation include not only joint surface incongruity, but also lower limb malalignment requiring revision surgery. Navigation has been proven effective for the intraoperative control of lower limb alignment during osteotomy and knee arthroplasty. In complex traumatic fractures, temporary fixation by a locking screw plate allows sensor positioning followed by navigation maneuvers to adjust lower limb alignment. If malalignment is found, the construct can be modified economically by altering the diaphyseal fixation without modifying the metaphyseal screws. The objective of this study was to describe the use of navigation in three patients who required internal fixation of tibial-plateau fractures.

What are the risk factors for dislocation in primary total hip arthroplasty? A multicenter case-control study of 128 unstable and 438 stable hips.

INTRODUCTION: Dislocation after total hip arthroplasty (THA) is a leading reason for surgical revision. The risk factors for dislocation are controversial, particularly those related to the patient and to the surgical procedure itself. The differences in opinion on the impact of these factors stem from the fact they are often evaluated using retrospective studies or in limited patient populations. This led us to carry out a prospective case-control study on a large population to determine: 1) the risk factors for dislocation after THA, 2) the features of these dislocations, and 3) the contribution of patient-related factors and surgery-related factors. HYPOTHESIS: Risk factors for dislocation related to the patient and procedure can be identified using a large case-control study. PATIENTS AND METHODS: A multicenter, prospective case-control study was performed between January 1 and December 31, 2013. Four patients with stable THAs were matched to each patient with a dislocated THA. This led to 566 primary THA cases being included: 128 unstable, 438 stable. The primary matching factors were sex, age, initial diagnosis, surgical approach, implantation date and type of implants (bearing size, standard or dual-mobility cup). RESULTS: The patients with unstable THAs were 67±12 [37-73]years old on average; there were 61 women (48%) and 67 men (52%). Hip osteoarthritis (OA) was the main reason for the THA procedure in 71% (91/128) of the unstable group. The dislocation was posterior in 84 cases and anterior in 44 cases. The dislocation occurred within 3 months of the primary surgery in 48 cases (38%), 3 to 12 months after in 23 cases (18%), 1 to 5years after in 20 cases (16%), 5 to 10years after in 17 cases (13%) and more than 10years later in 20 cases. The dislocation recurred within 6 months of the initial dislocation in 23 of the 128 cases (18%). The risk factors for instability were a high ASA score with an odds ratio (OR) of 1.93 (95% CI: 1.4-2.6), neurological disability (cognitive, motor or psychiatric disorders) with an OR of 3.9 (95% CI: 2.15-7.1), history of spinal disease (lumbar stenosis, spinal fusion, discectomy, scoliosis and injury sequelae) with an OR of 1.89 (95% CI: 1.0-3.6), unrepaired joint capsule (all approaches) with an OR of 4.1 (95% CI: 2.3-7.37), unrepaired joint capsule (posterior approach) with an OR of 6.0 (95% CI: 2.2-15.9), and cup inclination outside Lewinnek's safe zone (30°-50°) with OR of 2.4 (95% CI: 1.4-4.0). DISCUSSION: This large comparative study isolated important patient-related factors for dislocation that surgeons must be aware of. We also found evidence that implanting the cup in 30° to 50° inclination has a major impact on preventing dislocation. LEVEL OF EVIDENCE: Level III; case-control study.

Internal fixation of intra-capsular proximal femoral fractures in patients older than 80 years: Still relevant? Multivariate analysis of a prospective multicentre cohort.

BACKGROUND: Arthroplasty is now widely used to treat intra-capsular proximal femoral fractures (PFFs) in older patients, even when there is little or no displacement. However, whether arthroplasty is associated with lower mortality and complication rates in non-displaced or mildly displaced PFFs is unknown. The objectives of this prospective study were: (1) to evaluate early mortality rates with the two treatment methods, (2) to identify risk factors for complications, (3) and to identify predictors of functional decline. HYPOTHESIS: Arthroplasty and internal fixation produce similar outcomes in non-displaced fractures of patients older than 80 years with PFFs. MATERIAL AND METHODS: This multicentre prospective study included consecutive patients older than 80 years who were managed for intra-capsular PFFs at eight centres in 2014. Biometric data and geriatric assessment scores (Parker Mobility Score, Katz Index of Independence, and Mini-Nutritional Assessment [MNA] score) were collected before and 6 months after surgery. Independent risk factors were sought by multivariate analysis. We included 418 females and 124 males with a mean age of 87±4years. The distribution of Garden stages was stage I, n=56; stage II, n=33; stage III, n=130; and stage IV, n=323. Arthroplasty was performed in 494 patients and internal fixation in 48 patients with non-displaced intra-capsular PFFs. RESULTS: Mortality after 6 months was 16.4% overall, with no significant difference between the two groups. By multivariate analysis, two factors were significantly associated with higher mortality, namely, male gender (odds ratio [OR], 3.24; 95% confidence interval [95% CI], 2.0-5.84; P<0.0001) and high ASA score (OR, 1.56; 95% CI, 1.07-2.26; P=0.019). Two factors were independently associated with lower mortality, with 75% predictive value, namely, high haematocrit (OR, 0.8; 95% CI, 0.7-0.9; P=0.001) and better Parker score (OR, 0.5; 95% CI, 0.3-0.8; P=0.01). The cut-off values associated with a significant risk increase were 2 for the Parker score (OR, 1.8; 95% CI, 1.1-2.3; P=0.001) and 37% for the haematocrit (OR, 3.3; 95% CI, 1.9-5.5; P=0.02). Complications occurred in 5.5% of patients. Surgical site infections were seen in 1.4% of patients, all of whom had had arthroplasty. Blood loss was significantly greater with arthroplasty (311±197mL versus 201±165mL, P<0.0002). Dependency worsened in 39% of patients, and 31% of patients lost self-sufficiency. A higher preoperative Parker score was associated with a lower risk of high postoperative dependency (OR, 0.86; 95% CI, 0.76-0.97; P=0.014). DISCUSSION: Neither treatment method was associated with decreased mortality or better function after intra-capsular PFFs in patients older than 80 years. Early mortality rates were consistent with previous reports. Among the risk factors identified in this study, age, preoperative self-sufficiency, and gender are not amenable to modification, in contrast to haematocrit and blood loss. CONCLUSION: Internal fixation remains warranted in patients older than 80 years with non-displaced intra-capsular PFFs. LEVEL OF EVIDENCE: III, prospective case-control study.

Comparative study of computer-assisted total knee arthroplasty after opening wedge osteotomy versus after unicompartmental arthroplasty.

AIMS: The role of high tibial osteotomy (HTO) is being questioned by the use of unicompartmental knee arthroplasty (UKA) in the treatment of medial compartment femorotibial osteoarthritis. Our aim was to compare the outcomes of revision HTO or UKA to a total knee arthroplasty (TKA) using computer-assisted surgery in matched groups of patients. PATIENTS AND METHODS: We conducted a retrospective study to compare the clinical and radiological outcome of patients who underwent revision of a HTO to a TKA (group 1) with those who underwent revision of a medial UKA to a TKA (group 2). All revision procedures were performed using computer-assisted surgery. We extracted these groups of patients from our database. They were matched by age, gender, body mass index, follow-up and pre-operative functional score. The outcomes included the Knee Society Scores (KSS), radiological outcomes and the rate of further revision. RESULTS: There were 20 knees in 20 patients in each group. The mean follow-up was 4.1 years (2 to 18.7). The mean total KSS at last follow-up was 185.7 (standard deviation (sd) 5) in group 1 compared with 176.5 (sd 11) for group 2 (p = 0.003). The mean hip-knee-ankle angle was 180.2° (sd 3.2°) in group 1 and 179.0° (sd 2.2°) in group 2. No revision was required. CONCLUSION: We found that good functional and radiological outcomes followed revision of both HTO and UKA to TKA. Revision of HTO showed significantly better functional outcomes. These results need to be further investigated by a prospective randomised controlled trial involving a larger group of patients. Cite this article: Bone Joint J 2016;98-B:1620-4.

A novel carbon coating technique for foil bolometers.

Naked foil bolometers can reflect a significant fraction of incident energy and therefore cannot be used for absolute measurements. This paper outlines a novel coating approach to address this problem by blackening the surface of gold foil bolometers using physical vapour deposition. An experimental bolometer was built containing four standard gold foil bolometers, of which two were coated with 100+ nm of carbon. All bolometers were collimated and observed the same relatively high temperature, ohmically heated plasma. Preliminary results showed 13%-15% more incident power was measured by the coated bolometers and this is expected to be much higher in future TCV detached divertor experiments.