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While no gold standard exists for the management of Achilles tendon ruptures, surgical repair is common in healthy and active patients. Minimally invasive repair methods have become increasingly popular, while biomechanical equivalency hasn't been proven yet.A mid-substance Achilles tendon rupture was created 6 cm proximal to the calcaneal insertion in 27 fresh-frozen cadaveric ankles. Specimens were randomly allocated to 1 of 3 repair techniques: Huttunen et al. (2014) (1) PARS Achilles Jig System, Nyyssönen et al. (2008) (2) Achilles Midsubstance SpeedBridge™, Schipper and Cohen (2017) (3) Dresdner Instrument and subsequently subjected to cyclic loading with 250 cycles each at 1 Hz with 4 different loading ranges (20-100 N, 20-200 N, 20-300 N, and 20-400 N).After 250 cycles no significant differences in elongation were observed between PARS and Dresdner Instrument(p = 1.0). Furthermore, SpeedBridge™ repairs elongated less than either Dresdner Instrument (p = 0.0006) or PARS (p = 0.102). Main elongation (85%) occurred within the first 10 cycles with a comparable elongation in between 10 and 100 and 100-250 cycles. While all repairs withstood the first 250 cycles of cyclic loading from 20 to 100 N, only the PARS (468 ± 175) and Midsubstance SpeedBridge™ (538 ± 208) survived more cycles. Within all 3 groups suture cut out was seen to be the most common failure mechanism.Within all groups early repair elongation was seen. While this was least obvious within the SpeedBridge™ technique, ultimate strengths of repairs (cycles to failure) were comparable across PARS and SpeedBridge™ with a decline in the Dresdner Instrument group.

Councils and social housing organisations are looking to retrofit as a way to make their housing more energy efficient. Previous studies on energy use in social housing have generally focussed on the technological aspects (such as the potential savings possible by retrofitting this class of housing across the UK) or have involved one-off interventions or measures. During a two-year period, we worked with previously homeless people to reduce their energy consumption. The 32 participants lived in small blocks of flats (owned by a social housing organisation) that underwent retrofitting with air source heat pumps. We ran a three-phase tenant engagement programme to compare a range of approaches aimed at energy reduction. It was found that education, social norms, and self-awareness are all key components when it comes to initiating Environmentally Responsible Behaviours. The three approaches complemented each other, and these ought to be considered alongside technology provision if the aim is to reduce energy consumption. A number of reflections on the implementation of medium-term tenant engagement programmes are also presented.

Introduction People experiencing homelessness are susceptible to many adverse health events, including violence. The purpose of this study was to provide a descriptive analysis of homeless individuals who suffered a violent death in Maryland. Characterizing these deaths will provide a basis for additional analyses that can inform violence prevention activities. Methods This study used data from the Maryland Violent Death Reporting System to examine violent deaths of homeless people occurring from 2003 through 2011. This surveillance system collects information on all violent deaths occurring in Maryland. Victim demographics, injury and death information, precipitating circumstances contributing to deaths, and toxicology information were examined. All analyses were conducted in 2014 and 2015. Results Among all violent death victims from 2003 through 2011 (N=14,327), a total of 279 (2.0%) were identified as homeless victims. More than half (65.2%) of deaths were of undetermined intent, 21.2% were homicides, and 13.6% were suicides. The most common method of injury was poisoning (59.0%). Substance abuse and having a current mental health problem were among the most commonly reported circumstances relating to death. Conclusions This study found substance abuse and mental health problems to be major circumstances precipitating violent death among people experiencing homelessness. This study will serve as a starting point for more in-depth analyses on experiences of violent death among homeless people that can inform violence prevention policy and programming.

Government policy aimed at curbing carbon emissions often focusses on encouraging individual action, however the effectiveness of this approach has been limited. Investigations of why this might be have included segmentation, to identify different groups who undertake more or less action, and analysis of various “barriers” to action. Those on lower incomes who are not home owners have previously been found to be less engaged in seeking out energy efficiency information. Working with low-income tenants living in supported social housing we conducted three group interviews, accompanied by a 7-item scale measuring general attitude towards the environment. The interviews were aimed at opening up discussion about environmental and energy issues, including exploring more deeply what, for these participants, underlies barriers to conservation behaviours. We found participants to be very willing to engage in conversation and knowledgeable about a range of relevant issues. Barriers explored include: lack of confidence in existing levels of knowledge, habit, self-interest and lack of agency, and in all cases several different perspectives were voiced by participants. Implications for policy, interventions and public engagement are given, including ways to increase dialogue and reflection on sustainability issues for all sectors of society.

In case of hip revision arthroplasty, one component (cup/stem) is often well fixed and does not need to be exchanged. The newly implanted component needs to be compatible with the well-fixed implant. The combination of implants from different companies leads to "mix and match" or even mismatch between the implants.The objective of this work was to describe possible combinations including their specifications that need to be considered in partial exchange of hip prostheses. For this purpose the literature, surgical techniques of companies and judgements concerning this topic were analysed and our own results and experiences were included.Partial revision arthroplasty can be challenging and needs to be planned in detail. In case of isolated cup or inlay revision with exchange of a modular head the cone of the stem needs to be identified. A ceramic head may be used in revision with a titanium sleeve even from a different company as long as they are compatible. Patients however need to give their informed consent for this mix and match procedure. This procedure is done frequently and good study results support this, however from a juristic point of view a definite recommendation cannot be given. If the inlay of a cup is replaced, the original inlay should be used. If this is not available anymore, it can be manufactured as a special product in many cases. If this is also not possible, an inlay can also be cemented into a well-fixed cup. Biomechanical and clinical studies support this off-label technique. In case of an isolated exchange of the stem with a ceramic inlay that is retained in a well-fixed cup, the revision stem and ceramic head need to be from the same company as the cup. In case of ceramic fracture, a ceramic head with a titanium sleeve should be combined with a PE or ceramic inlay, a metal head or inlay should never be used.

Certification according to EndoCert in the field of arthroplasty in Germany aims at standardization of treatment and with this optimization of its quality. However, huge capital investment and efforts are necessary. There are currently more than 400 certified centres in Germany. Our Department of Orthopaedics at a German medical school was certified in the pilot phase. The aim of this study was to analyse whether there was a difference in the quality in the year after the certification. A second aim was to analyse whether the defined quality criteria are adequate for a university hospital.The quality criteria as defined by EndoCert were analysed in the year before (2011) and after certification (2012). The observed complications were noted for 1 year postoperatively. The clinical outcome was analysed with Western Ontario and McMaster University Osteoarthritis Index Score (WOMAC) 1 year postoperatively.There was no difference concerning the criteria analysed, including the clinical outcome in the year before and that after certification. In both years, nearly all criteria could be reached except the operation time and the infection rate in hip and knee revision surgery.Certification did not lead to a measurable change of the quality of care. Nearly all criteria, except the infection rate in revision arthroplasty (required: less than 3% at 1 year postop.) and the operation duration could be fulfilled. This rate as well as the operation duration should be revised. Certification according to EndoCert is an important tool to prove quality care, however big efforts and capital are needed. The criteria should be constantly revised and reduced, as these resources should not be missed in patient care.

The German Arthroplasty Registry (EPRD) was founded in 2010 and has been in full operation since 2014. Previous attempts at a systematic data collection of elective and non-elective knee and hip replacement in Germany failed mainly because of the long-term lack of funding. The EPRD is an interdisciplinary collaborative partnership between the German Association of Orthopedics and Orthopedic Surgery (DGOOC), all implant manufacturers of the German Medical Technology Association (BVMed), health insurers (AOK and the Association of Additional Healthcare Insurance) and hospitals (German Hospital Federation). As part of this cooperation a worldwide unique implant database has been set up, which includes all relevant components and a detailed description of implant specifications. This implant library enables a detailed evaluation of implant survival, revision rates and possible inferior implant performance of knee and hip replacements in Germany. At the end of 2015 the EPRD encompassed over 200,000 registered operations. Due to the high number of hip and knee arthroplasties in Germany with many different implants from different manufacturers there will be a rapid growth of data that are available for a national and also international comparison of the results.

Circa 30% der Frauen und 7% der Manner, bei denen eine primare huftendoprothetische Versorgung indiziert ist, leiden unter einer manifesten Osteoporose gemas WHO-Kriterien. Daher ist die praoperative Abschatzung der Risikofaktoren fur das Vorliegen einer Osteoporose wichtig, da diese ihrerseits einen Risikofaktor fur aseptische Lockerungen und periprothetische Frakturen darstellt. Eine patientengerechte Versorgung umfasst deshalb neben der Erkennung der Osteoporose die Wahl geeigneter Implantationstechniken und Prothesendesigns sowie auch die richtige Sekundarprophylaxe.

It has previously been suggested that consumers' product evaluations are positively affected by tactile interaction. However, it is not known if it is applicable to products that people usually touch for brief periods of time. This study sets out to explore whether it is possible to influence consumers' tactile perception of fast-moving consumer goods by altering the surface texture. In this study individual tactile sensing and visual appreciation were compared with the combined visual and tactile sensing of surface textures for two types of products (soap and biscuits). Three types of textures on the outside of either a soap or biscuit box and three separate sample swatches of the textures used on the boxes were used in the study. The three soap or biscuit boxes were visually presented to the participants. This was followed by a blind haptic evaluation of the three textures, and then by a combined visual and tactile evaluation of three differently textured boxes (either soap or biscuit boxes). The results suggest that a consumer's perception of the packaging of fast-moving consumer goods is affected more by vision than by touch, which raises some questions with regard to when marketers should encourage consumers to engage in extensive tactile interaction prior to purchase.

Introduction/Background Ropivacaine, bupivacaine and triamcinolone are used daily in injections during surgeries and pain therapy. The purpose was to analyze the ability of local anesthetics and cortisone to induce apoptosis and necrosis in fibroblasts, tenocytes and human mesenchymal stem cells (hMSC). Material and method Fibroblasts, tenocytes and adipose-derived hMSC were seeded in T25 flasks at a cell density of 0.5 × 104/cm2. Ropivacaine, bupivacaine and triamcinolone were added individually to the cells using concentrations of 0.5%, 0.25% and 0.125%. No addition of specimen was used as negative control. After 30 minutes incubation and medium change the cells were harvested at 1 hour, 24 hours and 7 days of incubation. Analysis via fluorescence-activated cell sorting (FACS) using double-staining with Annexin V and PI was performed. Annexin V stains apoptotic cells while PI enables necrotic cells to be differentiated. Therefore the FACS method allows a quantitative as well as a qualitative analysis of each cell population. SPSS was used for statistical analysis to determine significant difference (P > 0.05) between specimen and control groups. Results Bupivacaine shows necrosis-inducing effects on fibroblasts and tenocytes, the necrotic effect peaking at 0.5%. Ropivacaine and triamcinolone cause no significant necrosis. In comparison to fibroblasts and tenocytes, hMSC did not show significant necrotic or apoptotic effects after exposure to bupivacaine. Overall, no significant difference in apoptosis was detected between different cell lines, varying concentrations of the specimen or time of measurements. Conclusion Bupivacaine 0.5% has the highest necrosis-inducing effect on fibroblasts and tenocytes in comparison to ropivacaine, which causes less necrotic tissue. hMSC exhibited less necrosis compared to fibroblast and tenocytes. This may advise to prefer ropivacaine over bupivacaine for clinical practice.

PURPOSE The aim of the present study was to measure and interpret the change of the collodiaphyseal (CCD) angle and femoral anteversion after total hip replacement. METHODS We prospectively examined 52 patients with coxarthrosis, who were treated by total hip replacement. Preoperatively and postoperatively we used a standard X-ray ap view to measure the CCD angle and computerized tomography to determine the femoral anteversion. These projected angles were converted into the real angles by using the method of Konig and Schult. RESULTS On average the preoperative real CCD angle was 128 degrees (+/- 8.9 degrees) and the postoperative angle 145 degrees (+/- 4.8 degrees), preoperatively the real femoral anteversion angle was 14.1 degrees (+/- 6.9 degrees) and postoperatively 10.8 degrees (+/- 6.2 degrees). CONCLUSIONS The effect of the postoperative valgisation can be explained by the given CCD angle of the used femoral stem prosthesis of 140 degrees (cemented Weller II stem) and 145 degrees (cementless CLS classic stem). It is possible that due to the valgisation and the decreased offset of the femoral stem prosthesis compared to the preoperative conditions the gluteal muscles are insufficient and overloaded. It is also known that the change of the femoral anteversion from the physiological conditions causes an increase of the torsional moment. The resulting increased interface load could possibly be a reason for loosening of the femoral stem. The conclusion can be drawn that the CCD angle and the femoral anteversion should more carefully be considered by the surgeon in total hip replacement. This could be reached by an exact implantation technique and the choice of the appropriate stem prosthesis with different CCD angles.

AIM The aim of this study was the detection of areas at risk at the proximal femur after implantation of different femur neck prostheses using the photoelastic stress analysis. METHODS Twelve pairs of human femurs were used as examination material. The analysis of the stress pattern was done with a stepwise increasing load up to the quadruple of body weight before and after implantation of three models of femur neck prostheses which were implanted cementless. The "CUT" and "Cigar" models are coated with a tripod structure. The "Cigar" model has a lateral thrust plate. The lateral end of the "CUT" model is curved and this end is attached to the lateral corticalis. The third model, the "rip prosthesis" has two layers for rotational stability. Subsequently, the micromotions of the implanted prosthesis in the femural neck were examined with alternating weight loads (1000 +/- 700 N). RESULTS The Cigar prosthesis showed the most changes of stress distribution because of the lateral thrust plate with concentration of isochromatic lines to the lateral boring. In the region of the oseotomy an increase of strain up 1440 microm/m could be detected for the Cigar and up to 1000 microm/m for the rib prosthesis. The stress pattern after implantation of the CUT prosthesis remained very similar apart from a slight increase of stress values (720 microm/m). Only for the Cigar prostheses were the measured micromotions below the critical value for a possible osteointegration with a mean value of 134 microm/m. CONCLUSION The stress pattern after implantation of the CUT prosthesis remained most similar to the preinterventional stress distribution. Because of this, it is to be expected that the osseous modification would stay at a low level. The question of osteointegration can only be answered in long-term in-vivo studies.

Laser vibrometry measurements on a bowed violin are performed. A rotating disc apparatus, acting as a violin bow, is developed. It produces a continuous, long, repeatable, multi-frequency sound fro ...

Good violins have a broad hill in the 2–3 kHz range of their frequency response. This hill has previously been attributed to the first in-plane resonance of the violin bridge. Experiments prove, however, that the hill is the result of two forces acting in opposite directions at the bridge feet. The experiments reported here show that the hill can be “tuned” by altering the distance between the bridge feet. It can be tuned both in terms of frequency and level but the properties of the violin cannot be neglected.

Die chronisch rezidivierende multifokale Osteomyelitis (CRMO) ist eine abakterielle Form der Osteomyelitis, die vorwiegend im Kindesalter auftritt und in etwa 20% mit einer palmoplantaren Pustulose (PPP) assoziiert ist. Bei bislang ungeklarter Atiopathogenese wird die CRMO klinisch dem rheumatischen Formenkreis zugeordnet. Eigene Untersuchungen deuten darauf hin, dass erbliche Faktoren an der Entstehung beteiligt sind [27]. Diese Arbeit gibt einen Uberblick uber Klinik, Diagnostik und Therapiemoglichkeiten.

During a period of 6 months, 15 previously homeless male participants from a small town in the UK were encouraged to adopt an intrinsic and environmentally responsible attitude. The aim was to specifically reduce the participants' energy consumption. This was done through self- awareness sessions in parallel with traditional environmental educational sessions. Self-awareness was in this study used as a tool to help guide the participants towards a positive sense of self through the engagement of energy saving behaviours. The self-awareness sessions took place in the form of a series of small group sessions. Focus groups were conducted prior to the group sessions taking place and after they had been completed, in order to measure whether their environmentally held beliefs had changed. Each focus group was structured around their environmentally held beliefs and took around 1 hour. Thematic analysis was used to analyse the focus groups. The analysis revealed that at the onset the participants lacked interest in energy reduction behaviours. However, after having taken part in the self-awareness sessions it became evident that a shift in attitudes had occurred. This investigation was part of a bigger project with the participants in which their social housing underwent retrofitting with air-source heat pumps, to make the houses more energy efficient. Consequently, participants' energy usage was monitored using smart meters. Such monitoring supported the results from the thematic analysis in that it showed a decrease in energy use during the 6 months period the participants attended self-awareness sessions.

Unicompartmental knee arthroplasty (UKA) has become an accepted therapy for medial osteoarthritis. The main reasons for its popularity are the minimally invasive surgical technique and the reports of excellent long-term results including high patient satisfaction and good knee joint function especially in younger patients.The purpose of our retrospective study was to evaluate the physical activities of patients who had undergone an Oxford III medial UKA. Special attention was paid to implant positioning and osteoarthritis of the patellofemoral joint.Of 181 implanted Oxford III prosthesis, 136 (75.1%) could be followed up. The mean age at time of surgery was 65.2 years; the average time of follow-up was 4.2 years. In addition to a physical examination and x-ray, the following scores were obtained: WOMAC (Western Ontario and McMaster Osteoarthritis Index), OKS (Oxford Knee Score), KSS (Knee Society Score), UCLA activity and the Turba score.The majority of the patients (81%) returned to their sporting activity following knee surgery. Higher complication rates or progression of osteoarthritis associated with sporting activities were not observed. The active patients had significantly higher scores for the OKS, KSS, WOMAC, and UCLA scores. The correct implant position, especially avoiding overcorrection to valgus malalignment, is important for good clinical outcome.Our results demonstrate that a high degree of patient satisfaction in terms of physical and sporting activity can be achieved using the Oxford III UKA for medial osteoarthritis without an increased risk for complications.

Polyethylene is still one of the most important materials in the field of hip and knee arthroplasty. The clinical results of the last decades have helped to further develop polyethylene into a high-tech material. Progress in the development of new materials must be compared with the tried and tested ones to provide optimal and most individual patient care.This article gives an overview of the history and current application profile of the material ultra-high molecular weight polyethylene (UHMWPE) in hip and knee arthroplasty.With the aid of the current literature, new developments in the field of the material UHMWPE, also with respect to the biological activity of wear, the particular biomechanics of the knee joint as well as alternative hard-hard bearing surfaces in the hip, are represented in terms of implant safety.The problems concerning polyethylene are now well recognized. The disadvantages of the material UHMWPE could be consistently reduced based on material research so that modern polyethylenes have gradually been shown in clinical trials that they can be reliably used.Despite this the potential for improvement has still not yet been fully exploited. Any further development must be extensively tested both biomechanically and biologically before the material can be used in vivo. Long-term results are still necessary before a material can be accepted as being clinically safe.

We report about a 12-year-old boy with a Stickler syndrome. Because of osteonecrosis in the femoral head in MRI the initial diagnosis was dysplasia epiphysealis capitis femoris. The patient developed a progressive stiffness of the hip and a retinal detachment. A molecular investigation showed a Stickler syndrome. Stickler syndrome is an autosomal dominant hereditary disease. It has a very low incidence and a rare association with hip disease. Usually the patients suffer from hypermobility. In our case the course was atypical and diagnosis delayed.

Hip resurfacing arthroplasty is known to increase the metal ion concentration in the serum, urine and whole blood, with potentially adverse effects on the organism. However, only few data are available about the metal ion concentrations in erythrocytes, although they are directly exposed to the higher concentrations of the serum.The ion levels of chromium, cobalt, nickel and molybdenum in erythrocytes of 25 patients with a hip resurfacing implant were analysed with high resolution ICP-sf-MS (inductively-coupled-plasma-sector-field-mass-spectrometry). The results were compared to the ion levels in the serum and urine of the patients, and also to the ion levels of 27 control persons without an implant.Compared to the control group, ion levels in the erythrocytes of the hip resurfacing group were markedly increased for cobalt (0.10 vs. 3.26 microg/kg) and slightly for chromium (6.04 vs. 7.38 microg/kg). In contrast, ion levels in the serum of the hip resurfacing group were increased for cobalt (0.21 vs. 1.92 microg/l), chromium (1.48 vs. 5.64 microg/l), nickel (1.53 vs. 4.25 microg/l) and molybdenum (2.17 vs. 3.78 microg/l).Ion concentrations of cobalt and chromium are also increased in erythrocytes after hip resurfacing arthroplasty. Further research is required to evaluate the impact of the elevated ion levels on the erythrocytes, and to evaluate if metal ions also accumulate in other tissues of the body.

In contrast to fracture fixation, when performing an osteotomy the surgeon is able to plan preoperatively. The resulting fixation and compression of the bone fragments are the most important points. A stable osteosynthesis should prevent dislocation of bone fragments and improve bone healing. Beside plates, cerclages can be used for tension band or diaphysis bone fixation. Moreover, cortical or cancellous screws can be used for osteotomy fixation. This work describes biomechanical principles for fixation after an osteotomy with cerclages and cortical or cancellous screws. It also summarizes the materials and geometries used, as well as their influence on the stability of the osteosynthesis.

The action of the soundpost in a violin is not well understood and fundamental knowledge is needed. Therefore low‐frequency forced modes, operating deflection shapes, 250–600 Hz of a violin were investigated. Harmonic, sine wave, excitation was applied via the bridge (resembling playing) or via the sound from a loudspeaker. The latter excitation gives a reciprocal measure of radiativity. The modes were investigated with TV‐holography and electro‐acoustical admittance measurements. A carefully selected violin was investigated without soundpost, with soundpost, and with the soundpost position shifted toward the centerline. Answers were sought to three questions: Which are the violin modes forced via the bridge? To what extent do they radiate sound? What is the action of the soundpost? The observed modes were mostly not pure normal modes but mode combinations. Generally there is a nodal line close to the soundpost position of the plates. Schelleng has hypothesized that the main action of the soundpost is to make the violin nonsymmetric. The first top plate mode with soundpost can be looked upon as a combination of the first symmetric top plate mode and the first asymmetric mode without soundpost. The first mode is an efficient radiator and the second mode transfers the string vibrations via the bridge to the top plate efficiently. The asymmetric first mode with the soundpost is thus both excited and radiates sound. Our experimental results make the hypothesis plausible, but show that body (global) modes play an important role too. In the range 500 to 600 Hz, a body mode, C3, constitutes a major part. The C3 mode has a nodal line close to the normal soundpost position and is especially interesting as it seems to form a quality mark of a good violin.

One of the main goals of the preoperative planning of hip prostheses is adequate shaft positioning with reconstruction of leg length and offset. The purpose of this study was to compare the planned and achieved shaft positions using a modified program for migration measurement.In 60 cases of total hip replacement the preoperative planning was compared with the postoperative radiograph using a modified version of the well-established EBRA-FCA program. The results of this new measurement were compared to conventional measurements. In 25 cases the intraobserver and interobserver reliability was determined.The novel measurements correlated best with the measured distance between the greater trochanter and the center of rotation and yielded the best intraobserver and interobserver reliability. In general, cementless stems had a slightly more proximal position (0.65 mm) compared to cemented stems.The modified program for migration measurement facilitates a reproducible and fast comparison of the planned and achieved shaft positions thus implementing an early and objective control of postoperative shaft position.

Unicompartmental knee arthroplasty (UKA) has become a standard procedure with good clinical outcome in patients with isolated medial osteoarthritis of the knee. However, the survival rates of UKA are still inferior compared to that of total knee arthroplasty. Aseptic loosening and wear are responsible for more than 50% of revisions. Therefore, this study evaluated the influence of the tibial slope on the wear rate in a medial UKA.The wear rate of a medial mobile-bearing UKA (Univation® Aesculap, Tuttlingen, Deutschland) was evaluated according to the ISO 14243-1:2002(E) norm with a customized four-station servo-hydraulic knee wear simulator (EndoLab, Thansau, Germany). In the first group, the prostheses was medially implanted with 0° slope (n = 3) and in the second group the prostheses was medially implanted with 8° slope (n = 3). The lateral side was kept constant with 0° in both groups. For each implant, a total of 5.0 million cycles was performed and after every 0.5 million cycles the gravimetric wear rate was determined.The wear rate in the 0° slope group was 3.46 ± 0.59 mg/million cycles and therefore significantly higher than in the 8° slope group with 0.99 ± 0.42 mg/million cycles (p 0.01).An increase in the tibial slope leads to a reduced wear rate in a mobile-bearing UKA. Therefore, at least for this mobile-bearing UKA a higher tibial slope seems favorable to reduce the wear. However, before an optimal position of the tibial slope can be recommended, further investigations are required to evaluate the influence of the tibial slope on other factors, such as the ligament tension or the strain on the lateral compartment.

The present experimental investigation, using recently assembled advanced electro‐optical equipment for vibration analysis of three violins, was conducted to seek answers to three questions. A general or global question: Which parts of the violin body are vibrating the most? And two questions related to tonal quality: Are basic low‐frequency vibration modes of a musically superior instrument different from those of an inferior violin? Can some special vibration properties be found to support the ‘‘bridge hill?’’ Optically obtained vibration modes were recorded as well as frequency responses in the form of admittance measurements. The investigation showed that the vibration modes found earlier are representative both for the inferior violin and the musically superior instruments, although discrepancies can be seen, both in eigenmode shapes and admittance responses. The experimental results are also in quite good agreement with published results of the modal analysis of a violin. Further, the experimental results indicate that the transversal vibrations are mainly within the plates, but at low frequencies, the vibrations of the edges and of the ribs can be large and in‐plane as well as transversal. At higher frequencies, the transversal vibration amplitudes are small at the plate edges and larger inside. The top plate tends to have the largest amplitude of vibrations. In the 2.5‐kHz range the violin with the most clear ‘‘bridge hill’’ tends to have the largest vibrations of the plates.

The patellofemoral joint constitutes a complex anatomical and functional entity. The tensile force of the quadriceps femoris muscle is transmitted through the patella and patellar ligament onto the tibial tuberosity. This particular three-dimensional arrangement increases the torsional moment acting on the knee joint. Dynamic alignment of the patella is determined by trochlear geometry and is supported by active muscular and passive connective tissue stabilizers. In addition to the retinaculum of the patella, the medial patellofemoral ligament is attracting increasing clinical attention. Multidirectional motion of the patella is closely connected to retropatellar pressure distribution which can be modulated by moving the patellar ligament insertion. Implantation of a knee endoprosthesis changes the joint surface geometry and consequently patella kinematics and retropatellar pressure distribution. Finite element analysis provides the possibility to assess retropatellar pressure distribution before and after implantation of prostheses.

Total hip arthroplasty with a minimal-incision technique that can be performed in the widely used supine position. The accustomed and good overview of this position allows safe positioning of the implant and combines this with the advantage of a soft tissue preserving technique. All standard instruments and implants can be further applied.Primary and secondary coxarthrosis, femoral head necrosis.Revision surgery, severe anatomic deformity, implantation of hip resurfacing arthroplasty.Supine position. The skin incision runs from the innominate tubercle proximally and falls slightly in the dorsal direction (20-30°). Incision of the iliotibial tract and exposure of the vastogluteal muscle sling. Starting from the greater trochanter, the sinewy onset of the minimal and medium gluteal muscle is split with an arched-shaped incision, which also falls proximally in the dorsal direction. Exposition of the joint capsule, longitudinal incision and resection of the ventrolateral parts. Dislocation of the hip by a combined adduction and external rotation movement. Osteotomy of the femoral neck and resection of the femoral head are performed in a figure-of-four position without adduction. To prepare the acetabulum and to insert the cup, the leg is placed in neutral position with a slight flexion of 20° in the hip. Preparation of the femur and implantation of the stem is again performed in a figure-of-four position in adduction. Reduction of the hip and stepwise wound closure.Mobilization on postoperative day 1. Starting with half weight bearing and after completed wound healing rapid increase to full weight bearing. Intensive physiotherapy and rehabilitation. Thrombosis prophylaxis according to guidelines.The mini-incision approach has successfully been used in our clinic for years. Between September 2004 and November 2005, the less-invasive technique was evaluated in a randomized controlled trial with 51 patients (52 hips). Compared to the standard approach a significantly shorter incision length (8.9 vs. 14.0 cm) and a slightly lower blood loss (502 vs. 660 ml) were observed for the modified mini-Hardinge. Moreover, the mini-incision group showed slightly better functional results in the early course. A higher rate of implant malpositioning or a higher peri- and postoperative complication rate was not observed.

This paper reports on two exploratory studies aimed at understanding the extent to which people's responses to products are influenced by their ideas about the processes from which those products result. The first study involved analysing 400 comments from online discussions of two mobile phone handsets. The second study involved conducting and analysing interviews with 29 members of the public about their own mobile phone handsets. The results indicate that some (but not all) people are prone to view products not just as things that exist, but as the work of agents such as designers, manufacturers or brands. These agents were thought to hold certain beliefs about users and to shape products in the light of those beliefs. The products were also understood to result from motivations that the agents held (e.g. to make a profit) or constraints that acted upon them (e.g. manufacturing costs). Although only exploratory, the studies reveal some phenomena of product experience that are not discussed in the existing literature and they suggest ways in which those phenomena might be further studied.

Intralesional surgery of giant cell tumour of the bone (GCT) may result in a high rate of local recurrence. The introduction of local adjuvants, such as cementation, cryosurgery or phenolization, has proved to be successful in the reduction of recurrence rates. This study presents the results of a single institution in surgery of GCT with an evolution in treatment strategies.Forty primary and 25 recurrent surgical procedures in 46 patients with GCT of the bone with a median follow-up of 72 months were reviewed retrospectively. The mean age was 32.6 years (range 13.6-57.9 years). Forty-seven curettages and 18 resections were performed. For the curettages, a large bone window was cut followed by high speed burring and bone grafting or cementation. In 34 of 47 curettages and 7 of 18 resections, phenol was additionally applied.Two patients showed pulmonary metastasis, one died due to metastatic disease. In total, a third of the patients developed local recurrence (32.3%). This was evenly spread among primary and recurrent diesease (32.5% vs. 32%). Seven of 13 curettages without adjuvant recurred (53.9%), compared to 11 of 34 curettages with adjuvant phenol (32.4%). Three of 18 resections developed a recurrence (16.7%). No complications in respect to the use of phenol were seen.Phenolization is a safe local adjuvant therapy for GCT. Although the recurrence rate was lower with the use of phenol, this drop was not significant. The comparable high recurrence rate in our study, even if phenol was used, might be due to the fact that curettage was our favoured treatment, even in cases with an extensive juxta-articular tumour. We recommend adjuvant phenolization in the treatment of GCT of the bone after thorough curettage in applicable cases, including where cementation is used for defect filling.

This article describes an experimental study of the wave motion on the piano string and the corresponding spectra. The string motion was detected using an electrodynamic method. The measurements include typical initial string waveforms and spectra in the bass, mid, and treble at three dynamic levels (p–mf–f ). The interaction between hammer and string is also analyzed, including multiple contacts in the bass. The influence of hammer properties is investigated by shifting hammers and adjusting stiffness (‘‘voicing’’). A comparison between the string and bridge vibrations is presented, including the influence of the resonant tail lengths of the string (‘‘duplex scale’’). A brief account of the interaction between damper and string closes the study.

An interdisciplinary approach plays an important role in orthopaedic rheumatology. The aim of this study was to test the quality of an interdisciplinary consultation, which analyzed a pool of orthopaedic patients in terms of rheumatological disease.Orthopaedic patients (n=100) were transferred to a multidisciplinary team of experts in a two-stage selection process. Patient data were examined with regard to diagnosis and therapy. A patient interview analyzed the course of disease and effects of the consultation. Patients were questioned on the development of pain, diagnostics and therapy as well as their general satisfaction.Rheumatological disease was diagnosed in 42% of patients, while specific anti-rheumatic therapy was started in 41%. An improvement in symptoms as a result of treatment was seen in 63% of cases. Patient examinations revealed an above-average level of satisfaction in 63% of patients.Interdisciplinary consultation led to improved and faster diagnosis and therapy of rheumatological diseases, which was positively evaluated by the pool of patients treated.

For decades the cemented anchorage of hip prostheses, especially for elderly patients, is the standard procedure. The cementing technique has turned out to be the determining factor for the survival of the implant. In the last few years developments in this field have been able to further improve the long-term survival. Established components of the modern cementing technique are vacuum-mixed cements, medullary canal plugs, centralising elements und the use of jet-lavages. The design of the cemented shaft depends on the more important surface finish. In the most clinical studies, polished shafts turned out to be slightly superior as compared to shafts with rough surfaces.

The vibration levels in four traditional stringed instruments during playing have been investigated, including the double bass, violin, guitar, and the piano. The vibration levels, which were measured at several positions and at different dynamic levels, were evaluated with respect to reported thresholds for detection of vibrotactile stimuli. The results show that the vibration levels are well above threshold for almost all positions on the instruments in normal playing. It is concluded that the perceived vibrations may be of some assistance with regard to intonation in ensemble playing, in particular for the bass instruments. The finger forces exerted when playing the bowed strings, as well as the touch forces in piano playing were studied briefly. It was concluded that the kinesthetic forces perceived in playing may assist the timing in performance.

Bacterial osteomyelitis in children must be diagnosed quickly and requires immediate and adequate antibiotic treatment. Surgical interventions may be necessary. Infants as well as immunodeficient patients suffer more often from hematogenic bone infections than immunocompetent patients. According to recent findings, autoinflammatory nonbacterial osteitis is more probable in immunocompetent patients in good general condition and should always be considered as a differential diagnosis. Diagnostic and therapeutic approaches are presented when childhood osteomyelitis is suspected.