bluuebunny/crossref_metadata_2025 huggingface dataset:
Luminal epithelium in endometrial fragments affects their vascularization, growth and morphological development into endometriosis-like lesions
Authors: Feng Dilu , Menger Michael D. , Wang Hongbo , Laschke Matthias W.
Published: November 2013

In endometriosis research, endometriosis-like lesions are usually induced in rodents by transplantation of isolated endometrial tissue fragments to ectopic sites. In the present study, we investigated whether this approach is affected by the cellular composition of the grafts. For this purpose, endometrial tissue fragments covered with luminal epithelium (LE+) and without luminal epithelium (LE-) were transplanted from transgenic green fluorescent protein-positive (GFP+) donor mice into the dorsal skinfold chamber of GFP- wild-type recipient animals to analyze their vascularization, growth and morphology by means of repetitive intravital fluorescence microscopy, histology and immunohistochemistry during a 14-day observation period. LE- fragments developed into typical endometriosis-like lesions with cyst-like dilated endometrial glands and a well vascularized endometrial stroma. In contrast, LE+ fragments exhibited a polypoid morphology and a significantly reduced blood perfusion after engraftment, because the luminal epithelium prevented the vascular interconnection with the microvasculature of the surrounding host tissue. This was associated with a markedly decreased growth rate of LE+ lesions when compared to LE- lesions. Besides, we found that many GFP+ microvessels grew outside the LE- lesions and developed interconnections to the host microvasculature, indicating that inosculation is an important mechanism in the vascularization process of endometriosis-like lesions. Our findings demonstrate that the luminal epithelium crucially affects the vascularization, growth and morphology of endometriosis-like lesions. Therefore, it is of major importance to standardize the cellular composition of endometrial grafts in order to increase the validity and reliability of pre-clinical rodent studies in endometriosis research.
Vibratory Sensation Induced by Low-Frequency Noise: The Threshold for “Vibration Perceived in the Head” in Normal-Hearing Subjects
Authors: Takahashi Yukio
Published: November 2013

Our previous study, in which we measured the threshold levels for vibratory sensation induced by low-frequency noise under the condition that the subjects were allowed to perceive vibration in any part of the body, showed that the head was very sensitive to the vibratory sensation. In the present study, in which the head was designated as the body part that would perceive the vibration, we measured the threshold levels for experiencing “vibration perceived in the head” within the 16- to 80-Hz frequency range. The threshold levels for “vibration perceived in the head” were found to be very similar to the threshold levels measured in our previous study, which indicated the superior sensitivity of the head to vibratory sensation induced by low-frequency noise. A gap appeared around 40–50 Hz in the threshold level contour for “vibration perceived in the head”. In addition, the threshold levels for “vibration perceived in the head” increased when a subject wore an active noise cancelling earmuff. These results suggested the possibility that experiencing “vibration perceived in the head” was related to the pressure change in the ear.
Vertical and Fore-Aft Seat-to-Head Transmissibility Response to Vertical Whole Body Vibration: Gender and Anthropometric Effects
Authors: Dewangan Krishna N. , Shahmir Arman , Rakheja Subhash , Marcotte Pierre
Published: November 2013

In this study, the biodynamic responses to vertical vibration are investigated in terms of seat-to-head vibration transmissibility (STHT) to study the effects of gender and eleven different anthropometric parameters on the STHT responses in the vertical and fore-aft directions. The STHT response of 31 male and 27 female human subjects were measured under three levels of vertical vibration (0.25, 0.50 and 0.75 m/s2 rms acceleration) in the 0.50 to 20 Hz range, while seated without a back support and against a vertical back support with hands on a steering wheel. The results showed that the vertical and fore-aft STHT responses of the two genders were distinctly different. The primary resonance frequency of the male subjects was higher than the female subjects, while the peak magnitudes were comparable. The male subjects showed relatively greater softening effect, i.e. decrease in the primary resonance frequency with increase in excitation magnitude, as compared to the female subjects, irrespective of the sitting condition. The body mass revealed strong effect on both the male and female STHT responses. The primary resonance frequency of heavier subjects was lower than that of the lighter subjects, while the peak magnitude was higher for the heavier subjects. The male subjects showed significantly higher primary resonance frequency than the female subjects, even when comparable body mass, BMI and lean body mass were considered. The vertical STHT response of the two genders with same body fat mass was very similar for the sitting and excitation conditions considered in the study, particularly up to 10 Hz.
Application of an SMA Spring for Vibration Screen Control
Authors: Raczka Waldemar , Sibielak Marek , Kowal Janusz , Konieczny Jaroslaw
Published: November 2013

Use of springs made of an alloy with shape memory (SMA) to shape the dynamic characteristics of a resonance vibration screen is proposed in this paper. These springs change spring constant as a result of temperature changes. Thus it is possible to change their resonance frequency in real time. In the paper a mathematical model of a controlled SMA spring was formulated and its parameters were identified. In the model both the effect of spring coefficient changes and damping changes depending upon alloy temperature and spring vibration frequency were taken into consideration. Experimental investigations of the examined spring and screen physical model were carried out and selected characteristics were also included. The investigations were carried out at the Dynamics and Control of Structures Laboratory of AGH University of Science and Technology. The control law was formulated. Simulation investigations of the mathematical vibration screen model in both open and closed loop systems were made. It was shown that the elaborated control system is robust of vibration mass changes by as much as ±30%.
Adaptive Sliding Mode Vibration Control of a Nonlinear Smart Beam: A Comparison with Self-Tuning Ziegler-Nichols PID Controller
Authors: Oveisi Atta , Gudarzi Mohammad
Published: November 2013

This paper investigates the vibration control of geometrically nonlinear beam with Macro Fiber Composite (MFC) actuators using two different adaptive control algorithms. A complete mathematical modeling is presented in order to find the dynamic equation of motion. Then, a robust adaptive fuzzy control algorithm for controlling the proposed mechanical structure is introduced. This controller includes a fuzzy scheme and a robust controller. Based on sliding mode controller a fuzzy system is introduced to mimic an ideal controller. The robust controller is designed based on compensation of the difference between the fuzzy controller and the ideal controller. The parameters of the fuzzy system and uncertainty bound of the robust controller are adjusted adaptively. The adaptive laws are designed based on the Lyapunov stability theorem to reach the stability of the closed-loop system. Meanwhile, for comparison purposes the presented controller is compared with self tuning Ziegler-Nichols PID controller for both robustness and vibration suppression performance aspects. Effectiveness of these two control strategies is evaluated by numerical simulations. Detailed analysis for the closed-loop system is carried out to evaluate the vibration controlling performance under different output excitation, robustness of the closed-loop system under sudden loading and the effect of initial condition on vibration characteristic.
Analysis of the Adsorption Behaviour of Cadmium on Aluminium-Pillared Diatomite in a Solid/Liquid System Using Classical Adsorption Theory
Authors: Zhu Jian , Wang Ping , Lei Mingjing , Zhang Weili , Wang Taoyuan , Wu Xiaofu
Published: November 2013

A readily available effective adsorbent is necessary to adsorb heavy-metal ions from aqueous solutions. In this study, a novel adsorbent with good adsorption properties [Al3+–oligomer–pillared diatomite (Al3+–oligomer–PD)] was prepared and was used to adsorb Cd2+ ions in a solid/liquid system. The property and nature of the Cd2+ ions adsorbed on the surface of the Al3+–oligomer–PD were studied by performing a series of adsorption tests and related surface property analyses. Our study results show that owing to a more favourable pore structure, the PD has a higher adsorption property compared with natural diatomite (ND) and most other common adsorbents. The adsorption capacity of PD is 27.36% greater than ND and also achieves an optimal value of 10.05 mg/l. Certain parameters have a significant effect on Cd2+ ion adsorption. The most suitable isotherm and kinetics models for describing the adsorption of Cd2+ ions are the Freundlich and pseudo-second-order models. The nature of Cd2+ ion adsorption on PD is favourable, physical, spontaneous, exothermic and disorder increasing. The results of the study suggest that PD is an ideal adsorbent for the removal of cadmium ions from aqueous solutions.
Polyacrylamide-Based Sorbents for the Removal of Hazardous Metals
Authors: Moulay Saâd , Bensacia Nabila , Garin François , Fechete Ioana , Boos Anne
Published: November 2013

Polyacrylamide was synthesized and chemically modified (PAAm) with 1,2,4,5-tetrahydroxybenzene (THB) or benzene-1,2,4,5-tetrol by applying the reaction conditions of Minisci. A degree of modification as high as 42% was obtained under the following conditions: temperature of 70–80 °C, reaction time of 3 hours and [2,5-dihydroxy-1,4-benzoquinone]-to-[AAm] ratio of 2.5. The synthesized PAAm and its modified form (THB–PAAm) were characterized by UV–Vis, Fourier transform infrared spectroscopy, 13C nuclear magnetic resonance, differential scanning calorimetry and thermogravimetric analysis. A severe degradation of the modified PAAm was observed, as confirmed by its relatively low molecular weight. Yet, the glass-transition temperature of THB–PAAm was found to be drastically lower than that of pristine PAAm, 63.1 versus 161.19 °C. A study of copper(II) adsorption by the cross-linked PAAm and THB–PAAm resins was undertaken by varying the following parameters: pH, time, temperature, ionic strength, sorbent mass and initial copper(II) concentration. Adsorption of Pb(II) and Cd(II) by the resins and their corresponding desorption extents were estimated. A new way of crosslinking polyacrylamide and its modified form through an oxidative decarboxylation process is applied.
Removal of Sodium Dodecylbenzenesulphonate and Cetyltrimethylammonium Bromide Using a Carbon Composite Derived from Modified Zn–Al-Layered Double Hydroxide
Authors: Santos Rodrigo Morais Menezes dos , Gonçalves Rosembergue Gabriel Lima , Pinto Marina de Carvalho Eufrásio , Prado Roberta Gomes , Constantino Vera Regina Leopoldo , Costa Liovando Marciano da , Pinto Frederico Garcia , Tronto Jairo
Published: November 2013

We describe the synthesis of a composite carbon derived from zinc–aluminium-layered double hydroxides. The material was characterized by powder X-ray diffraction, Fourier transform infrared/attenuated total reflectance spectroscopy, thermogravimetric analysis–differential scanning calorimetry–mass spectrometry, measurement of BET specific surface area, zeta-potential analysis and scanning electron microscopy. The resulting material was used for adsorption studies with an anionic surfactant, sodium dodecylbenzenesulphonate, and a cationic surfactant, cetyltrimethylammonium bromide, as adsorbates. The adsorption of the surfactants was well described by the typical Langmuir pattern. An investigation of the influence of initial pH of a medium on surfactant adsorption showed that high pH values decrease the adsorption capacity of the adsorbent. The adsorption processes were exothermic. The results also showed that the adsorption of the two surfactants was chemical and that the kinetic models were best described by a pseudo-second-order model.
Identification of Tall Shear Buildings under Unknown Seismic Excitation with Limited Output Measurements
Authors: Lei Ying , He Mingyu , Liu Chao , Lin Shu-Zhi
Published: November 2013

Due to the fact that some structural external excitations such as earthquakes and wind forces can not be accurately measured under actual operating conditions, it is necessary to investigate algorithms for structural identification under unknown earthquakes. In this paper, an algorithm based on the extended Kalman estimator approach is proposed for the identification of structural parameters and unknown excitation of tall shear-type buildings with only partial measurements of structural absolute acceleration responses. The equation of motion of a tall shear building under ground motion is established in the absolute co-ordinate system, in which the ground-motion input is applied to the 1st floor of the building as an unknown excitation. Based on substructure approach, the tall building is decomposed into substructures. For each substructure above the 1st floor, substructural relative responses and parameters are identified by extended Kalman estimator. For the substructure containing the 1st floor, it is proposed that substructural extended state vector is firstly identified by the extended Kalman estimator and the unknown excitation is subsequently estimated by least-squares estimation. Then, the 1st story stiffness is estimated based on structural eigenvalue equation and the expansion of the determinate of the structural eigen-matrix. The unknown ground motion is identified by the Newmark-β method. A numerical simulation example demonstrates the efficiency of the proposed algorithm.
Inward Inversion Studies on the Stepped Shape Frusta
Authors: Gupta Pramod Kumar , Sahu Ram Ranjan
Published: November 2013

This paper describes the plastic deformation and energy absorption of aluminum stepped geometry frusta, under axial compression between two flat plates. Experiments were carried out on aluminum frusta having stepped geometry. Geometrically these frusta were made with different diameter to thickness ratio at a height, different angle of steps & the thickness of frusta were also varied. Finite element (FE) analysis was carried out for experimental simulation. Deformation results and correlation from experiment and numerical simulations are discussed. Effect of various ratios like height to diameter, height to thickness, step geometry etc on deformation behavior, has been discussed in details, in this paper.
Investigation of Construction Vertical Deformation and Pre-Deformation Control for Three Super High-Rise Buildings
Authors: Fan Feng , Wang Huajie , Zhi Xudong , Huang Gang , Zhu Enchun , Wang Hong
Published: November 2013

The cumulative problem of vertical deformation for super high-rise buildings during construction becomes more significant as the height of structure continue to increase nowadays, for which the investigation of the characteristics of the vertical deformation is worth conducting. First, the technique of simulation of the construction process for super high-rise buildings was developed systematically, with which simulation of construction of the three typical high-rise buildings was conducted. The effect of concrete creep, shrinkage and leveling during construction were investigated and the characteristics of the vertical deformation revealed. Furthermore, a method of pre-deformation for super high-rise buildings was presented with deformation compensation stepwise. The total vertical displacement and the relative deformation between the inner core tube and the outer steel frame were chosen as the control targets in the method, which can be used to address the cumulative problem of vertical deformation and to provide technical support for deformation control in construction of super high-rise buildings.
Adaptive Trigonometric Wavelet Composite Beam Element Method
Authors: He Wen-Yu , Ren Wei-Xin
Published: November 2013

It is always an issue to use as few finite elements as possible to reduce a computational load with the precision assured to solve engineering problems. In this paper, the trigonometric wavelet function and polynomial function are combined together to be the displacement interpolation function of beam element. Accordingly, the trigonometric wavelet composite beam element is formulated based on the principle of potential energy minimum to carry out the bending, free vibration and buckling analysis of beam structures. Such a trigonometric wavelet composite beam element utilizes the advantages of both conventional finite element and trigonometric wavelet finite element. As the order of wavelet function can be enhanced easily and the multi-resolution can be achieved by the multi-scales of wavelet function, the trigonometric wavelet composite finite element provides an alternate way to realize the adaptive analysis. Numerical examples have illustrated that the proposed trigonometric wavelet composite beam element is effective and the solution accuracy can be improved adaptively with enhancing the scale order of wavelet.
Strain-Gradient-Dependent Stress-Strain Curve for Normal-Strength Concrete
Authors: Ho J.C.M. , Peng J.
Published: November 2013

The stress-strain distribution of concrete in the compression zone of reinforced concrete (RC) flexural members is the most important parameter for assessing the ultimate flexural strength and ductility. Currently, the stress-strain curve of concrete developed in flexure is taken as the uni-axial compressive curve incorporating a scale-down factor k3, which is the ratio of the maximum concrete stress developed under flexure to the concrete cylinder strength. In current RC design codes, the ratio of the equivalent concrete stress to cylinder strength is taken as constant equal to 0.85 for normal-strength concrete but reduces as concrete strength increases. However, in a recent study carried out by the authors, it was found that the maximum concrete stress developed in the flexure increases significantly as the strain gradient (ratio of extreme concrete strain to neutral axis depth) increases, until reaching a maximum limit. Therefore, the value of k3 should not be taken as a constant for flexural RC members. In this study, the authors will adopt the results obtained in the previous experimental tests on concentrically, eccentrically and horizontally loaded RC columns to derive the stress-strain curve of concrete under different extents of strain gradient. The derived values of k3 are then correlated to the strain gradient using empirical equation. The applicability of the proposed equation is checked by comparing the flexural strengths of NSC beams and columns so calculated with those experimentally measured by different researchers, in which good agreement has been obtained.
Numerical Approach to the Live Load Factor for RC Structures as a Function of Life-Time
Authors: Zadeh Hany Jawaheri , Mejia Felipe , Nanni Antonio
Published: November 2013

The live load factor, as a function of the expected life-time, is computed for cast-in-place reinforced concrete elements (i.e., beam, slab and column) for a combination of dead and live loads. The accuracy of the reliability analysis is enhanced by taking advantage of the Rackwitz-Fiessler method which in turn is corroborated by Monte Carlo simulation applied to the calculation of the target reliability indices of each structural element type. As an example, the formulation of live load factor is reversed to demonstrate how the life-time or the probability of failure are affected as the actual design deviates from the requirements of the current building code.
Large-Scale Testing of Coupled Shear Wall Structures with Damping Devices
Authors: Ahn Tae-Sang , Kim Young-Ju , Kim Sang-Dae
Published: November 2013

When coupled shear wall (CSW) systems are built in a high seismic region, excessive shear forces are induced in the coupling beams. As a result of these shear forces, brittle failure of coupling beams and wall-coupling beam joints may occur or shear walls may yield first. The ductility demands on coupling beams can also be of critical concern. To solve these problems, new damping systems are proposed to improve the seismic performance of high-rise coupling shear wall structures. The proposed systems, which are CSW systems with a metallic damper or a friction damper, offer important advantages over the conventional reinforced concrete CSW systems: increasing energy dissipation capacity and reducing damage to the structures. This paper presents the results of large-cale cyclic tests of damped CSW systems. Test results show that the proposed systems exhibit a stable hysteretic response. In addition, the energy dissipation in these systems is concentrated in the energy dissipation devices, while the inelastic behavior of the beams and walls is prevented through appropriate capacity design.
Hemodynamic Sensor in Cardiac Implantable Electric Devices: The Endocardial Accelaration Technology
Authors: Sacchi Stefania , Contardi Danilo , Pieragnoli Paolo , Ricciardi Giuseppe , Giomi Andrea , Padeletti Luigi
Published: November 2013

There have been substantial progresses in the technology of cardiac implantable electric devices (CIEDs) during the past decades. One of the progresses is represented by the development of a hemodynamic sensor embedded at the tip of a pacing lead that measures myocardial contractility by the analysis of myocardial mechanical vibrations occurring during the cardiac cycle. This sensor, providing continuous hemodynamic monitoring, could play an important role in clinical practice because of several clinical applications in CIEDs recipients. The objectives of this work are to report how this sensor operates and to review the main findings about its clinical applications.
Modelling of Thermal Hyperemia in the Skin of Type 2 Diabetic Patients
Authors: Bandini Andrea , Orlandi Silvia , Manfredi Claudia , Evangelisti Attilio , Barrella Massimo , Bevilacqua Maurizio , Bocchi Leonardo
Published: November 2013

The microcirculatory response to thermal stimulation involves both an axon reflex and NO‐mediated activation. The analysis of the microcirculatory flow following thermal stimulation may therefore enhance the detection of any impairment of the small unmyelinated fibres that are involved in the axon reflex. The aim of this work is to establish a method of non‐invasive measurement of small fibre impairment. The microcirculatory flow in response to local heating is measured by using a laser Doppler instrument, and mathematically modelled to extract a set of quantitative parameters. The results confirm that there is a significant difference in the parameters modelling the axon reflex between diabetic and control subjects, while no significant difference is found in the parameters modelling the NO‐mediated activation.
Measurement of Lower Limb Joint Kinematics using Inertial Sensors During Stair Ascent and Descent in Healthy Older Adults and Stroke Survivors
Authors: Laudanski Annemarie , Brouwer Brenda , Li Qingguo
Published: November 2013

This study validated the feasibility of inertial sensors in estimating lower limb joint kinematics during stair ambulation in healthy older adults and stroke survivors. Three dimensional motion data were collected using an inertial sensor‐based system from 9 persons with stroke and 9 healthy older adults as they ascended and descended a staircase at a self‐selected pace. The measured joint angles were compared with a laboratory‐based motion capture system by computing differences in range of motion (RoM), grand mean error, standard deviation, and coefficients of multiple correlations. For stroke survivors, differences in RoM measurements between these two systems were determined to be 3.3 ± 8.1°, while the highest correlations were found in the estimation of sagittal plane joint angles after offset correction. Results suggest that the inertial sensor system is suitable for estimating major joint angles in healthy older adults as well as the RoM for stroke survivors. New calibration procedures are necessary for applying the technology to a stroke population.
Screw fixation of medial malleolar fractures
Authors: Parker L. , Garlick N. , McCarthy I. , Grechenig S. , Grechenig W. , Smitham P.
Published: November 2013

The AO Foundation advocates the use of partially threaded lag screws in the fixation of fractures of the medial malleolus. However, their threads often bypass the radiodense physeal scar of the distal tibia, possibly failing to obtain more secure purchase and better compression of the fracture.

We therefore hypothesised that the partially threaded screws commonly used to fix a medial malleolar fracture often provide suboptimal compression as a result of bypassing the physeal scar, and proposed that better compression of the fracture may be achieved with shorter partially threaded screws or fully threaded screws whose threads engage the physeal scar.

We analysed compression at the fracture site in human cadaver medial malleoli treated with either 30 mm or 45 mm long partially threaded screws or 45 mm fully threaded screws. The median compression at the fracture site achieved with 30 mm partially threaded screws (0.95 kg/cm2 (interquartile range (IQR) 0.8 to 1.2) and 45 mm fully threaded screws (1.0 kg/cm2 (IQR 0.7 to 2.8)) was significantly higher than that achieved with 45 mm partially threaded screws (0.6 kg/cm2 (IQR 0.2 to 0.9)) (p = 0.04 and p < 0.001, respectively). The fully threaded screws and the 30mm partially threaded screws were seen to engage the physeal scar under an image intensifier in each case.

The results support the use of 30 mm partially threaded or 45 mm fully threaded screws that engage the physeal scar rather than longer partially threaded screws that do not. A 45 mm fully threaded screw may in practice offer additional benefit over 30 mm partially threaded screws in increasing the thread count in the denser paraphyseal region.

Cite this article: Bone Joint J 2013;95-B:1662–6.
Avascular necrosis after chemotherapy for haematological malignancy in childhood
Authors: Salem K. H. , Brockert A-K. , Mertens R. , Drescher W.
Published: November 2013

Avascular necrosis (AVN) is a serious complication of high-dose chemotherapy for haematological malignancy in childhood. In order to describe its incidence and main risk factors and to evaluate the current treatment options, we reviewed 105 children with a mean age of 8.25 years (1 to 17.8) who had acute lymphoblastic or acute myeloid leukaemia, or a non-Hodgkin’s lymphoma. Overall, eight children (7.6%) developed AVN after a mean of 16.8 months (8 to 49). There were four boys and four girls with a mean age of 14.4 years (9.8 to 16.8) and a total of 18 involved sites, 12 of which were in the femoral head. All these children were aged > nine years (p < 0.001). All had received steroid treatment with a mean cumulative dose of prednisone of 5967 mg (4425 to 9599) compared with a mean of 3943 mg (0 to 18 585) for patients without AVN (p = 0.005). No difference existed between genders and no thrombophilic disorders were identified. Their initial treatment included 11 core decompressions and two bipolar hip replacements. Later, two salvage osteotomies were done and three patients (four hips) eventually needed a total joint replacement. We conclude that AVN mostly affects the weight-bearing epiphyses. Its risk increases with age and higher steroid doses. These high-risk patients may benefit from early screening for AVN.

Cite this article: Bone Joint J 2013;95-B:1708–13.
Ceramic-on-ceramic bearings in young patients
Authors: Chana R. , Facek M. , Tilley S. , Walter W. K. , Zicat B. , Walter W. L.
Published: November 2013

We report the clinical and radiological outcomes of a series of contemporary cementless ceramic-on-ceramic total hip replacements (THRs) at ten years in patients aged ≤ 55 years of age. Pre- and post-operative activity levels are described. A total of 120 consecutive ceramic cementless THRs were performed at a single centre in 110 patients from 1997 to 1999. The mean age of the patients at operation was 45 years (20 to 55). At ten years, four patients had died and six were lost to follow-up, comprising ten hips. The mean post-operative Harris hip score was 94.7 (55 to 100). Radiological analysis was undertaken in 90 available THRs of the surviving 106 hips at final review: all had evidence of stable bony ingrowth, with no cases of osteolysis. Wear was undetectable. There were four revisions. The survival for both components with revision for any cause as an endpoint was 96.5% (95% confidence interval 94.5 to 98.7). The mean modified University of California, Los Angeles activity level rose from a mean of 6.4 (4 to 10) pre-operatively to 9.0 (6 to 10) at the ten-year post-operative period.

Alumina ceramic-on-ceramic bearings in cementless primary THR in this series have resulted in good clinical and radiological outcomes with undetectable rates of wear and excellent function in the demanding younger patient group at ten years.

Cite this article: Bone Joint J 2013;95-B:1603–9.
Two-stage revision for the treatment of the infected total elbow arthroplasty
Authors: Peach C. A. , Nicoletti S. , Lawrence T. M. , Stanley D.
Published: November 2013

We report our experience of staged revision surgery for the treatment of infected total elbow arthroplasty (TEA). Between 1998 and 2010 a consecutive series of 33 patients (34 TEAs) underwent a first-stage procedure with the intention to proceed to second-stage procedure when the infection had been controlled. A single first-stage procedure with removal of the components and cement was undertaken for 29 TEAs (85%), followed by the insertion of antibiotic-impregnated cement beads, and five (15%) required two or more first-stage procedures. The most common organism isolated was coagulase-negative Staphylococcus in 21 TEAs (62%).

A second-stage procedure was performed for 26 TEAs (76%); seven patients (seven TEAs, 21%) had a functional resection arthroplasty with antibiotic beads in situ and had no further surgery, one had a persistent discharge preventing further surgery.

There were three recurrent infections (11.5%) in those patients who underwent a second-stage procedure. The infection presented at a mean of eight months (5 to 10) post-operatively. The mean Mayo Elbow Performance Score (MEPS) in those who underwent a second stage revision without recurrent infection was 81.1 (65 to 95).

Staged revision surgery is successful in the treatment of patients with an infected TEA and is associated with a low rate of recurrent infection. However, when infection does occur, this study would suggest that it becomes apparent within ten months of the second stage procedure.

Cite this article: Bone Joint J 2013;95-B:1681–6.
Popliteal artery injury during knee replacement
Authors: Bernhoff K. , Rudström H. , Gedeborg R. , Björck M.
Published: November 2013

Popliteal artery injury (PAI) is a feared complication during knee replacement. Our aim was to investigate those injuries that occurred in association with knee replacement in terms of the type of injury, treatment and outcomes.

From our national vascular registry (Swedvasc) and the Swedish Patient Insurance databases a total of 32 cases were identified. Prospective data from the registries was supplemented with case-records, including long-term follow-up.

We estimated the incidence during 1998 to 2010 to be 0.017%. In our series of 32 patients with PAI occurring between 1987 and 2011, 25 (78%) were due to penetrating trauma and seven were caused by blunt trauma. The patients presented in three ways: bleeding (14), ischaemia (7) and false aneurysm formation (11), and five occurred during revision surgery. A total of 12 injuries were detected intra-operatively, eight within 24 hours (3 to 24) and 12 at more than 24 hours post-operatively (2 to 90 days). Treatment comprised open surgery in 28 patients. Patency of the vascular repair at 30 days was 97% (31 of 32, one amputation). At the time of follow-up (median 546 days, mean 677 days (24 to 1251)), 25 patients had residual symptoms. Of seven patients with a complete recovery, six had had an early diagnosis of the PAI during the procedure, and were treated by a vascular surgeon in the same hospital.

PAI is a rare adverse event during knee replacement surgery. The outcome following such events is often adversely affected by diagnostic and therapeutic delay. Bleeding and false aneurysm were the most common clinical presentations.

Cite this article: Bone Joint J 2013;95-B:1645–9.
Total knee replacement in patients with concomitant back pain results in a worse functional outcome and a lower rate of satisfaction
Authors: Clement N. D. , MacDonald D. , Simpson A. H. R. W. , Burnett R.
Published: November 2013

This study assessed the effect of concomitant back pain on the Oxford knee score (OKS), Short-Form (SF)-12 and patient satisfaction after total knee replacement (TKR). It involved a prospectively compiled database of demographics and outcome scores for 2392 patients undergoing primary TKR, of whom 829 patients (35%) reported back pain. Compared with those patients without back pain, those with back pain were more likely to be female (odds ratio (OR) 1.5 (95% confidence interval (CI) 1.3 to 1.8)), have a greater level of comorbidity, a worse pre-operative OKS (2.3 points (95% CI 1.7 to 3.0)) and worse SF-12 physical (2.0 points (95% CI 1.4 to 2.6)) and mental (3.3 points (95% CI 2.3 to 4.3)) components.

One year post-operatively, those with back pain had significantly worse outcome scores than those without with a mean difference in the OKS of 5 points (95% CI 3.8 to 5.4), in the SF-12 physical component of 6 points (95% CI 5.4 to 7.1) and in the mental component of 4 points (95% CI 3.1 to 4.9). Patients with back pain were less likely to be satisfied (OR 0.62, 95% CI 0.5 to 0.78).

After adjusting for confounding variables, concomitant back pain was an independent predictor of a worse post-operative OKS, and of dissatisfaction. Clinicians should be aware that patients suffering concomitant back pain pre-operatively are at an increased risk of being dissatisfied post-operatively.

Cite this article: Bone Joint J 2013;95-B:1632–9.
Simple debridement has little useful value on the clinical course of recalcitrant ulnar wrist pain
Authors: Nishizuka T. , Tatebe M. , Hirata H. , Shinohara T. , Yamamoto M. , Iwatsuki K.
Published: November 2013

The purpose of this study was to evaluate treatment results following arthroscopic triangular fibrocartilage complex (TFCC) debridement for recalcitrant ulnar wrist pain. According to the treatment algorithm, 66 patients (36 men and 30 women with a mean age of 38.1 years (15 to 67)) with recalcitrant ulnar wrist pain were allocated to undergo ulnar shortening osteotomy (USO; n = 24), arthroscopic TFCC repair (n = 15), arthroscopic TFCC debridement (n = 14) or prolonged conservative treatment (n = 13). The mean follow-up was 36.0 months (15 to 54). Significant differences in Hand20 score at 18 months were evident between the USO group and TFCC debridement group (p = 0.003), and between the TFCC repair group and TFCC debridement group (p = 0.029). Within-group comparisons showed that Hand20 score at five months or later and pain score at two months or later were significantly decreased in the USO/TFCC repair groups. In contrast, scores in the TFCC debridement/conservative groups did not decrease significantly. Grip strength at 18 months was significantly improved in the USO/TFCC repair groups, but not in the TFCC debridement/conservative groups. TFCC debridement shows little benefit on the clinical course of recalcitrant ulnar wrist pain even after excluding patients with ulnocarpal abutment or TFCC detachment from the fovea from the indications for arthroscopic TFCC debridement.

Cite this article: Bone Joint J 2013;95-B:1687–96.
Management and incidence of tibial tubercle fractures in bicondylar fractures of the tibial plateau
Authors: Maroto M. D. , Scolaro J. A. , Henley M. B. , Dunbar R. P.
Published: November 2013

Bicondylar tibial plateau fractures result from high-energy injuries. Fractures of the tibial plateau can involve the tibial tubercle, which represents a disruption to the extensor mechanism and logically must be stabilised. The purpose of this study was to identify the incidence of an independent tibial tubercle fracture in bicondylar tibial plateau fractures, and to report management strategies and potential complications. We retrospectively reviewed a prospectively collected orthopaedic trauma database for the period January 2003 to December 2008, and identified 392 bicondylar fractures of the tibial plateau, in which 85 tibial tubercle fractures (21.6%) were identified in 84 patients. There were 60 men and 24 women in our study group, with a mean age of 45.4 years (18 to 71). In 84 fractures open reduction and internal fixation was undertaken, either with screws alone (23 patients) or with a plate and screws (61 patients). The remaining patient was treated non-operatively. In all, 52 fractures were available for clinical and radiological assessment at a mean follow-up of 58.5 weeks (24 to 94). All fractures of the tibial tubercle united, but 24 of 54 fractures (46%) required a secondary procedure for their tibial plateau fracture. Four patients reported pain arising from prominent tubercle plates and screws, which in one patient required removal. Tibial tubercle fractures occurred in over one-fifth of the bicondylar tibial plateau fractures in our series. Fixation is necessary and can be reliably performed with screws alone or with a screw and plate, which restores the extensor mechanism and facilitates early knee flexion.

Cite this article: Bone Joint J 2013;95-B:1697–1702.
Does human immunodeficiency virus status affect early wound healing in open surgically stabilised tibial fractures?
Authors: Howard N. E. , Phaff M. , Aird J. , Wicks L. , Rollinson P.
Published: November 2013

We compared early post-operative rates of wound infection in HIV-positive and -negative patients presenting with open tibial fractures managed with surgical fixation.

The wounds of 84 patients (85 fractures), 28 of whom were HIV positive and 56 were HIV negative, were assessed for signs of infection using the ASEPIS wound score. There were 19 women and 65 men with a mean age of 34.8 years. A total of 57 fractures (17 HIV-positive, 40 HIV-negative) treated with external fixation were also assessed using the Checkett score for pin-site infection. The remaining 28 fractures were treated with internal fixation. No significant difference in early post-operative wound infection between the two groups of patients was found (10.7% (n = 3) vs 19.6% (n = 11); relative risk (RR) 0.55 (95% confidence interval (CI) 0.17 to 1.8); p = 0.32). There was also no significant difference in pin-site infection rates (17.6% (n = 3) vs 12.5% (n = 5); RR 1.62 (95% CI 0.44 to 6.07); p = 0.47).

The study does not support the hypothesis that HIV significantly increases the rate of early wound or pin-site infection in open tibial fractures. We would therefore suggest that a patient’s HIV status should not alter the management of open tibial fractures in patients who have a CD4 count > 350 cells/μl.

Cite this article: Bone Joint J 2013;95-B:1703–7.
The Ponseti method in the treatment of children with idiopathic clubfoot presenting between five and ten years of age
Authors: Banskota B. , Banskota A. K. , Regmi R. , Rajbhandary T. , Shrestha O. P. , Spiegel D. A.
Published: November 2013

Our goal was to evaluate the use of Ponseti’s method, with minor adaptations, in the treatment of idiopathic clubfeet presenting in children between five and ten years of age. A retrospective review was performed in 36 children (55 feet) with a mean age of 7.4 years (5 to 10), supplemented by digital images and video recordings of gait. There were 19 males and 17 females. The mean follow-up was 31.5 months (24 to 40). The mean number of casts was 9.5 (6 to 11), and all children required surgery, including a percutaneous tenotomy or open tendo Achillis lengthening (49%), posterior release (34.5%), posterior medial soft-tissue release (14.5%), or soft-tissue release combined with an osteotomy (2%). The mean dorsiflexion of the ankle was 9° (0° to 15°). Forefoot alignment was neutral in 28 feet (51%) or adducted (< 10°) in 20 feet (36%), > 10° in seven feet (13%). Hindfoot alignment was neutral or mild valgus in 26 feet (47%), mild varus (< 10°) in 19 feet (35%), and varus (> 10°) in ten feet (18%). Heel–toe gait was present in 38 feet (86%), and 12 (28%) exhibited weight-bearing on the lateral border (out of a total of 44 feet with gait videos available for analysis). Overt relapse was identified in nine feet (16%, six children). The parents of 27 children (75%) were completely satisfied.

A plantigrade foot was achieved in 46 feet (84%) without an extensive soft-tissue release or bony procedure, although under-correction was common, and longer-term follow-up will be required to assess the outcome.

Cite this article: Bone Joint J 2013;95-B:1721–5.
Distraction osteogenesis in the treatment of long bone defects of the lower limbs
Authors: Papakostidis C. , Bhandari M. , Giannoudis P. V.
Published: November 2013

We carried out a systematic review of the literature to evaluate the evidence regarding the clinical results of the Ilizarov method in the treatment of long bone defects of the lower limbs.

Only 37 reports (three non-randomised comparative studies, one prospective study and 33 case-series) met our inclusion criteria. Although several studies were unsatisfactory in terms of statistical heterogeneity, our analysis appears to show that the Ilizarov method of distraction osteogenesis significantly reduced the risk of deep infection in infected osseous lesions (risk ratio 0.14 (95% confidence interval (CI) 0.10 to 0.20), p < 0.001). However, there was a rate of re-fracture of 5% (95% CI 3 to 7), with a rate of neurovascular complications of 2.2% (95% CI 0.3 to 4) and an amputation rate of 2.9% (95% CI 1.4 to 4.4).The data was generally not statistically heterogeneous. Where tibial defects were > 8 cm, the risk of re-fracture increased (odds ratio 3.7 (95% CI 1.1 to 12.5), p = 0.036).

The technique is demanding for patients, illustrated by the voluntary amputation rate of 1.6% (95% CI 0 to 3.1), which underlines the need for careful patient selection.

Cite this article: Bone Joint J 2013;95-B:1673–80.
Treatment of osteochondral defects of the talus with a metal resurfacing inlay implant after failed previous surgery
Authors: van Bergen C. J. A. , van Eekeren I. C. M. , Reilingh M. L. , Sierevelt I. N. , van Dijk C. N.
Published: November 2013

We have evaluated the clinical effectiveness of a metal resurfacing inlay implant for osteochondral defects of the medial talar dome after failed previous surgical treatment. We prospectively studied 20 consecutive patients with a mean age of 38 years (20 to 60), for a mean of three years (2 to 5) post-surgery. There was statistically significant reduction of pain in each of four situations (i.e., rest, walking, stair climbing and running; p ≤ 0.01). The median American Orthopaedic Foot and Ankle Society ankle-hindfoot score improved from 62 (interquartile range (IQR) 46 to 72) pre-operatively to 87 (IQR 75 to 95) at final follow-up (p < 0.001). The Foot and Ankle Outcome Score improved on all subscales (p ≤ 0.03). The mean Short-Form 36 physical component scale improved from 36 (23 to 50) pre-operatively to 45 (29 to 55) at final follow-up (p = 0.001); the mental component scale did not change significantly. On radiographs, progressive degenerative changes of the opposing tibial plafond were observed in two patients. One patient required additional surgery for the osteochondral defect. This study shows that a metal implant is a promising treatment for osteochondral defects of the medial talar dome after failed previous surgery.

Cite this article: Bone Joint J 2013;95-B:1650–5.
First-time knowledge brokers in health care: the experiences of nurses and allied health professionals of bridging the research-practice gap
Authors: Wright Nicola
Published: November 2013

This study describes the experiences of nurses and allied health professionals as first-time knowledge brokers, attempting to bridge the research-practice gap within health care. A qualitative study using in-depth interviews and documentary analysis was conducted. The data was analysed using a thematic analysis strategy. Participants were 17 knowledge brokers and five individuals mentoring and supporting them. Four themes described their experiences: expectations, pragmatics, emotional reactions and outcomes. In summary, knowledge brokering roles had multi-level benefits. However, there is a lack of support and recognition for these roles at an organisational level, making these activities difficult to sustain in the long term.
Is ‘better regulation’ possible? Formal and substantive quality in the impact assessments in education and culture of the European Commission
Authors: Souto-Otero Manuel
Published: November 2013

This article explores the initial results produced by the European Commission’s ‘better regulation agenda’, which aims to stimulate productivity and employment, on the use of evidence and its potential to enhance democratic governance. The article finds that implausible rational models of policy making dictate the ways in which the Commission is expected to conceive its programmes, and these models are adopted to legitimise rather than inform decisions. This negatively affects the processes by which interventions are designed and their social credibility. These processes are illustrated through an analysis of EU regulatory impact assessments in lifelong learning, culture, youth and citizenship during 2002-07.
Role of evidence in maternal health policy processes in Vietnam, India and China: findings from the HEPVIC project
Authors: Mirzoev Tolib , Green Andrew , Nancy Gerein , Stephen Pearson , Philippa Bird , Thu Ha Bui Thi , Ramani Karaikurichi , Qian Xu , Yang Xiaoguang , Mukhopadhyay Maitrayee , Soors Werner
Published: November 2013

This paper explores the role of evidence in maternal health policy processes in Vietnam, India and China. Both formal and informal types of evidence were used; and differences were found between the stages of policy processes. Evidence used mostly covered easily quantifiable issues and clearly identifiable technical solutions. Different policy actors were involved; actors’ evidence preferences were affected by their power, agendas, values and perceived characteristics of robust evidence. To enhance evidence role there is a need to: develop culture of evidence-informed policies; value different evidence types; ensure evidence use throughout policy processes; recognise and manage actors’ agendas; and develop context-specific strategies.