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Background Knee joint distraction (KJD) is a new joint-preserving surgery technique that, like high tibial osteotomy (HTO), aims to delay total knee arthroplasty (TKA) especially in younger patients with knee osteoarthritis (OA). One year after treatment, KJD demonstrated similar beneficial outcomes compared to HTO and compared to TKA.1 2 Objectives To compare radiographic joint space width and clinical outcome over two-years for KJD vs TKA and for KJD vs HTO and to additionally study KJD cartilage repair by evaluation of systemic collagen type II markers. Methods End-stage knee OA patients considered for TKA were randomised to KJD (n=20; KJDTKA) or TKA (n=40). Medial compartmental knee OA patients with a varus deviation of WOMAC questionnaires (100 best) and VAS pain scores (0 best) were assessed at baseline (0), 3, 6, 12, 18 and 24 months. In the KJD groups, serum PIIANP and urine CTXII levels, as markers for collagen type II synthesis and breakdown, were determined over time. Normalised Z-indexes were calculated (Zindex=ZPIIANP – ZCTXII) to express net collagen type II synthesis. The minimum and mean joint space width (JSW) of the most affected compartment (MAC) were measured with KIDA software on standardised radiographs taken at 0, 12 and 24 months. Results Of the 129 included patients, 1, 6, 3, and 5 patients were lost in the KJDTKA, TKA, KJDHTO, and HTO group respectively, for various reasons. One-year structural and clinical outcomes were statistically significantly improved as reported before, and these beneficial effects sustained for at least two years after treatment when compared to baseline (figure 1A-C). At 24 months, there were no significant differences between the KJDHTO and HTO groups (all p>0.25) and between the KJDTKA and TKA group, except for VAS pain score in favour of TKA at 24 months (p=0.037; figure 1B). Compared to baseline, the ratio of synthesis over breakdown of collagen type II biomarkers (figure 1D) was significantly decreased at 3 months (−0.45±0.20; p=0.032) after which this reversed towards an increase over time (at 24 months+0.59±0.19; p=0.004). Conclusions Sustained improvement of clinical benefit and increase in JSW after KJD is demonstrated for over 2 years of follow-up in case of treatment of patients with medial compartmental knee OA indicated for HTO or patients with end-stage knee OA indicated for TKA. The structural cartilage repair observed on radiographs is supported by a beneficial change in systemic biomarkers for collagen type II. For the HTO-indicated population, results of KJD patients were similar to those of HTO. For the TKA-indicated patients, TKA appeared to result in a slightly better clinical outcome, however at the expense of the native knee joint. References [1] vd Woude JA, et al. Bone Joint J2017;99-B(1):51–58. [2] vd Woude JA, et al. Knee Surg Sports Traumatol Arthrosc2017;25(3):876–886. Disclosure of Interest None declared

Background Placement of a total knee arthroplasty (TKA) in case of end-stage knee osteoarthritis (OA) in young patients is less successful than in elderly, with high revisions rates later in life (1). Recently knee joint distraction (KJD) showed results of clinical improvement and tissue structure modification in patients with knee OA (2) postponing a TKA. The duration of these beneficial effects is yet unclear. Objectives We evaluated whether the clinical improvement and tissue structure modification in knee OA sustain and persist on MRI and X-rays 5 years after distraction. Methods Patients (n=20; Results From 20 patients (age 49±6 yrs), two withdrew informed consent and three other patients were treated with TKP (after three and four years), so the survival of the knee joint was 80% at 5 years. Moreover, there was persistent clinical improvement compared to baseline sustaining over time: Δ WOMAC +21,1 points (CI:8,9-33,3; p=0.002), Δ VAS pain -27,6mm (CI:-13,3-42,0; p In addition, minimum radiographic JSW was increased at five years as compared to pre-treatment values: Δ+0,43mm (CI:0,02-0,84; p=0.040). Taking natural loss of cartilage thickness into account, this change was significantly different from the changes as a result of extrapolated natural progression (Δ-0,39mm and Δ-0,18mm, respectively) resulting at 5 years in a difference of +0,65mm (CI:0,07-1,23; p=0.031) and of +0,41mm (CI:0,07-0,74; p=0.020) for mean JSW on X-ray and average cartilage thickness on MRI, respectively. Conclusions In young OA patients, TKA can be postponed for at least five years in 80% of the patients. KJD treatment results in persistent clinical benefit and an increase in cartilage thickness and JSW. The effects were not as strong as observed 1 and 2 years after treatment, still they represented a significant structural benefit compared to the natural course of the disease. Joint distraction has great potential to effectively postpone TKA and as such represents a promising therapeutic option for young patients with severe knee OA. References Julin J, Jamsen E, Puolakka T,et al. Younger age increases the risk of early prosthesis failure following primary total knee replacement for osteoarthritis. A follow-up study of 32,019 total knee replacements in the Finnish Arthroplasty Register. Acta orthopaedica. 2010;81(4):413-9. Wiegant K, van Roermund PM, et al. Sustained clinical and structural benefit after joint distraction in the treatment of severe knee osteoarthritis. Osteoarthritis and cartilage/OARS, Osteoarthritis Research Society. 2013 Nov;21(11):1660-7. PubMed PMID: 23954704. Acknowledgements This study was supported by the Dutch Arthritis Foundation. Disclosure of Interest None declared

Background Knee joint distraction (KJD) results in clinical improvement and cartilage repair in young, active patients with knee OA. Another knee preserving treatment, in medial compartment knee osteoarthritis, is a high tibial osteotomy (HTO), which has good mid-term and longer follow-up results. However, no comparative data on efficacy is available. A RCT was set out and determined whether there was a clinical relevant difference in functional outcome after 1-year between KJD and HTO. Methods 69 patients with medial osteoarthritis were included and randomized to KJD (23 patients) or HTO (46 patients). A WOMAC questionnaire (100 being the best) was assessed at baseline (BL) and 12 months. EQ-5D index score was used to assess improvement in the quality of life (1 being the best). Joint space width (JSW) of the medial compartment was determined on standardized semi-flexed x-rays at BL and 1-year. Results 45 patients received HTO (mean age at surgery 49.4±1.0, mean BMI 27.2±0.5 kg/m 2 and mean Kellgren & Lawrence grade 2.5±0.1). 22 patients received KJD (mean age at surgery 51.2±1.1, mean BMI 27.5±0.7, mean Kellgren and Lawrence grade 2.3±0.2). Total WOMAC scores demonstrated significant clinical improvement in both groups. The KJD group increased from 57±17 points at BL to 76±17 points at 1-year (p Conclusions Six weeks of KJD does not lead to a clinical relevant difference in outcome compared with HTO after 1-year. Importantly both KJD and HTO lead to substantial newly formed cartilage-like tissue with superiority of KJD. Thus KJD is an alternative option in patients less suitable for HTO. Disclosure of Interest None declared

Background In osteoarthritis knee joint distraction (KJD) provides clinical benefit and tissue structure modification at 1 year and beyond. During the previous regime of an 8-week distraction period patients visited every 2 weeks day care practice for temporarily removal of the distraction frame. 8 weeks of intermittent KJD with frequent hospital visits is perceived as a considerable burden. This study evaluates whether 6 weeks of continuous KJD gives similar tissue structure repair and clinical benefit compared to eight weeks of KJD at 1-year follow-up. Methods Both groups consisted of 20 patients with knee OA and were treated with 5 mm joint distraction by use of an external fixator for 8 weeks with every 2 weeks CPM or 6 weeks continuously. WOMAC questionnaires were assessed, representing the clinical outcome. Structural outcome was quantified as mean joint space width (JSW) on standardized semi-flexed x-rays at baseline and one-year of follow-up using KIDA. T-tests were applied to analyze change over time. Results Clinical improvement compared to baseline (BL) was observed in both groups. The 6-week group showed a comparable increase from 53±17 points at BL to 76±17 points at one-year follow up (p Conclusions Six weeks of continuous KJD gives significant clinical and structural improvement. Moreover, 6-weeks of continuous distraction treatment does not lead to a stiffer knee in comparison with the “intermittent” 8-week treatment. Acknowledgements ZonMw (The Netherlands Organisation for Health Research and Development) and the Dutch Arthritis Association support this study. Disclosure of Interest None declared

Background Placement of a total knee prosthesis (TKP) in case of end-stage knee OA in young patients is less successful than in the elderly, with high revision rates of up to 44% later in life. [1,2] However, in severe end-stage knee OA, effective joint saving treatments are scarce. Recently, knee joint distraction (KJD) showed results of clinical improvement and cartilaginous tissue repair in patients with knee OA. [3] However, no comparative data on efficacy is available. A RCT was set out and determined whether there was a clinical relevant difference between KJD and TKP in clinical outcome 1-year after treatment. Methods 60 patients with severe knee osteoarthritis were included and randomized to KJD (20 patients) or TKP (40 patients). As clinical outcome parameter a WOMAC questionnaire (100 being the best) and a VAS Pain (0 mm being the best) were assessed at baseline (BL) and 12 months. Off all values mean ± SEM is given. Results 26 patients, who received a TKP, had at least one-year of follow-up and of the patients who received KJD 16 at least one-year of follow-up available at the cut-off date (December 31st 2014). The 26 patients in the TKP group had a mean age at surgery of 54.8±1.2, a mean BMI of 29.6±0.7 kg/m2 and a mean Kellgren & Lawrence grade of 2.7±0.1. The 16 patients in the KJD group had a mean age at surgery of 57.1±1.8, a mean BMI of 26.8±1.0 and a mean Kellgren & Lawrence grade of 3.6±0.2. Total WOMAC scores demonstrated significant clinical improvement in both groups (see also figure 1). The KJD group increased from 50±3 points at BL to 80±4 points at 1-year (p Conclusions KJD does not lead to a clinical relevant difference in outcome compared with TKP after 1-year. Importantly KJD preserves the knee-joint and therefore represents a promising therapeutic option for young patients with severe knee OA. References Julin J, Jamsen E, Puolakka T, Konttinen YT, Moilanen T. Younger age increases the risk of early prosthesis failure following primary total knee replacement for osteoarthritis. A follow-up study of 32,019 total knee replacements in the Finnish Arthroplasty Register. Acta orthopaedica. 2010;81(4):413-9. Kurtz SM, Lau E, Ong K, Zhao K, Kelly M, Bozic KJ. Future young patient demand for primary and revision joint replacement: national projections from 2010 to 2030. Clinical orthopaedics and related research. 2009;467(10):2606-12. Wiegant K, van Roermund PM, Intema F, Cotofana S, Eckstein F, Mastbergen SC, et al. Sustained clinical and structural benefit after joint distraction in the treatment of severe knee osteoarthritis. Osteoarthritis and cartilage/OARS, Osteoarthritis Research Society. 2013;21(11):1660-7. Acknowledgements ZonMw (The Netherlands Organisation for Health Research and Development) and the Dutch Arthritis Association support this study. Disclosure of Interest None declared

The aim of this paper is to assess the costs and effects of stent implantation versus percutaneous transluminal coronary angioplasty (PTCA). Data have been taken from both the BENESTENT-I and BENESTENT-II pilot study. Effects are expressed in terms of event-free survival and costs include those of the initial hospitalization and those during follow-up. The costs per additional event-free survivor after 7 months are estimated at Dfl 88,315, Dfl 28,127 and Dfl 6747 using respectively the results from the BENSTENT-I study, the BENESTENT-II pilot study and phase IV of the BENESTENT-II pilot study. Significant decreases in complications and ischaemic events have made stent implantation not only the most favourable in terms of event-free survival but also in terms of cost effectiveness.

The production of fimbrial adhesins K99 and F41 by enterotoxigenic Escherichia coli has been measured in steady-state chemostat experiments at various specific growth rates (microseconds) and in a recycling fermentor across a range of mu values falling to less than 0.004 h-1. It has been demonstrated that the production of K99 and F41 fimbriae is correlated with mu both in aerobic and anaerobic chemostat experiments. A significant production of fimbriae was only detected at mu values higher than 0.2 h-1. This behavior was further examined by culturing the bacteria in a recycling fermentor with complete biomass retention. It could be shown that the production of K99 and F41 fimbriae only occurred during balanced growth, with a high biomass yield at mu values higher than 0.04 h-1 corresponding to mass doubling times (td) of less than 17 h. The production of both fimbriae halted during balanced growth with a lower biomass yield (at mu values between 0.012 and 0.04 h-1 corresponding to td values between 17 and 58 h) and unbalanced stringent growth (at mu values lower than 0.012 h-1 or td values higher than 58 h). The external pH of the medium greatly influenced the production of both K99 and F41 fimbriae. At pH values lower than 7, the production of fimbriae was strongly inhibited. Also, at pH values higher than 7, a decrease in production was observed. The consequences of the observed phenomena for the pathogenic behavior of this E. coli strain are discussed.

Inelastic scattering of 480 MeV and 340 MeV α particles on 208Pb, 116Sn and 58Ni has been used in a search for high excitation energy giant multipole resonances, up to E* = 60 MeV for 208Pb and E* = 45 MeV for 116Sn and 58Ni. Above the well known quadrupole and monopole resonances, there is clear evidence for a very wide set of negative parity modes (including the already known high energy octupole), followed and mixed with another very wide set of positive parity resonances, extending up to the limits of the experimental spectra.

The systematics of the excitation energy of the giant dipole, monopole, and quadrupole resonances are shown to exhibit an isotopic effect. For a given element, the excitation energy of the transition decreases faster with the increasing neutron number than the empirical laws fitting the overall data. This effect is discussed in terms of the available models.