Die Dezentrierung des Schultergelenkes als Spätfolge nach hemi- und totalendoprothetischem Gelenkersatz

BACKGROUND

Migration after shoulder arthroplasty can induce muscular dysbalance and instability of the shoulder joint. The aim of this study was to analyse the frequency, causes and consequences of secondary migration after shoulder arthroplasty.

METHODS

107 shoulder arthroplasties in patients with primary osteoarthritis (OA, n = 83) or avascular necrosis of the humeral head (AVN, n = 24), were followed clinically and radiographically over a period of 1 to 10 years.

RESULTS

17 Patients (16 %) developed secondary migration of the prosthesis. These were determined after a mean period of 33 months after shoulder arthroplasty. Patients with secondary migration of the prosthesis showed a worse function with a mean Constant score (CS) of 52.3 points in comparison to the patient group without migrated shoulder arthroplasties (62 points) (p = 0.038). In patients with total shoulder arthroplasty (TSA, n = 75), migration was observed in 13 % of cases during follow-up. Lucent lines at the glenoid were found in radiographs in 55 % of migrated shoulders and in 52 % of non-migrated shoulders (p = 0.633). The Constant score showed no significant difference between the groups (non-migrated shoulders 63 points, migrated shoulders 61 points, p > 0.5). Migration was seen in 22 % (7/32 patients) after hemiarthroplasty, however, no significant difference could be found between the respective Constant scores for migrated (47.7 points) or non-migrated (55.1 points) shoulders (p = 0.447). In patients with OA there was no significant difference in Constant score between migrated and non-migrated shoulders (p = 0.331), whereas patients with AVN showed significantly worse function after migrated shoulder arthroplasty (p = 0.007).

CONCLUSION

Migration after total shoulder arthroplasty leads in the medium term neither to an increased frequency of lucent lines at the glenoid nor to a worsening of the functional score in comparison to non-migrated prosthesis. In patients with AVN, migration is accompanied by a worsening of the functional score and can consequently be regarded as a negative prognostic factor.

Prävalenz und Korrelate der Osteoarthrose in der BRD

BACKGROUND

The purpose of the paper was to generate up-to-date, representative osteoarthritis prevalence data for individual population subgroups and to identify potential risk factors.

MATERIAL AND METHODS

A cross-sectional study, the "First National Health Survey", investigated the prevalence of osteoarthritis, comorbidity and health-relevant behaviours of the post-unification German population on the basis of interviews with physicians and medical evaluations conducted in the period from October 1997 to March 1990. The study was based on a net sample comprising 6205 subjects aged 18-79 years.

RESULTS

The three main correlates for osteoarthritis are age, obesity and occupational stress factors. Osteoarthritis patients are more likely to have osteoporosis, thyroid disease, chronic bronchial disease, hypertension and elevated blood lipids, but do not tend to have a higher incidence of diabetes.

CONCLUSION

Our data show the importance of preventive behavioural approaches such as weight management and workplaces designed to limit joint overuse.

Bone Mineral Density and Degenerative Changes of the Lumbar Spine in Former Elite Athletes

The aim of this study was to assess bone mineral density (BMD) and degenerative changes in the lumbar spine in male former elite athletes participating in different track and field disciplines and to determine the influence of body composition and degenerative changes on BMD. One hundred and fifty-nine former male elite athletes (40 throwers, 97 jumpers, 22 endurance athletes) were studied. Anthropometric (age, body mass index [BMI]) and sport-specific data (personal best, intensity, duration, and time since termination of competitive sports career as well as current sporting activity) were collected. Degenerative changes of the lumbar spine in lateral view were evaluated by using the Kellgren and Lawrence Score. Bone mineral density of the lumbar spine was measured in an anterior-posterior view with dual energy X-ray absorptiometry (DEXA, T-score). Throwers had a higher body mass index than jumpers and endurance athletes. Throwers and jumpers had higher BMD (T-LWS) than endurance athletes. Bivariate analysis revealed a negative correlation of BMD (T-score) with age and a positive correlation with BMD and Kellgren score (p<0.05). Even after multiple adjustment for confounders lumbar spine BMD is significantly higher in throwers, pole vaulters, and long- and triple jumpers than in marathon athletes. Different types of mechanical loading caused by sporting activities seem to influence the BMD of the lumbar spine, even if different body constitutions (i.e. BMI) and age, training history, and degenerative changes in the lumbar spine of former throwers, jumpers, and endurance athletes are taken into consideration.

Towards a medically approved technology for alginate-based microcapsules allowing long-term immunoisolated transplantation

The concept of encapsulated-cell therapy is very appealing, but in practice a great deal of technology and know-how is needed for the production of long-term functional transplants. Alginate is one of the most promising biomaterials for immunoisolation of allogeneic and xenogeneic cells and tissues (such as Langerhans islets). Although great advances in alginate-based cell encapsulation have been reported, several improvements need to be made before routine clinical applications can be considered. Among these is the production of purified alginates with consistently high transplantation-grade quality. This depends to a great extent on the purity of the input algal source as well as on the development of alginate extraction and purification processes that can be validated. A key engineering challenge in designing immunoisolating alginate-based microcapsules is that of maintaining unimpeded exchange of nutrients, oxygen and therapeutic factors (released by the encapsulated cells), while simultaneously avoiding swelling and subsequent rupture of the microcapsules. This requires the development of efficient, validated and well-documented technology for cross-linking alginates with divalent cations. Clinical applications also require validated technology for long-term cryopreservation of encapsulated cells to maintaining a product inventory in order to meet end-user demands. As shown here these demands could be met by the development of novel, validated technologies for production of transplantation-grade alginate and microcapsule engineering and storage. The advances in alginate-based therapy are demonstrated by transplantation of encapsulated rat and human islet grafts that functioned properly for about 1 year in diabetic mice.

Quality assurance for diabetic retinopathy telescreening

AIMS

TOSCA was an EU-Commission supported international research project designed to develop telescreening services in diabetic retinopathy and glaucoma. This paper describes the quality assurance methods developed for the diabetic retinopathy telescreening service within the TOSCA project.

SETTING

The study was performed in 1895 patients with diabetes between 2000 and 2002 at diabetic retinopathy screening sites in five European countries. Data were analysed centrally.

METHODS

Patients attending each clinic's diabetic retinopathy screening service received standardized retinal photography. The images and associated data were transferred electronically to a remote location for grading. Each photographer uploading images and each grader downloading images for assessment was controlled by a systematic quality management approach. The quality assurance measures defined were image quality, intragrader reliability. A cockpit chart was developed for the management and presentation of relevant results and quality measures. For the intragrader reliability tests, 10% of the images were processed for a second grading. An algorithm for calculating differences between repeated gradings was developed.

RESULTS

The assessment of image quality for the different sites showed that only 0-0.7% were unassessable. One hundred per cent agreement for both gradings was achieved in 50-85% of graded cases, depending on site and grader, and an agreement better than 95% in 71-100% of cases.

CONCLUSIONS

A telemedicine-supported quality assurance process is practical and advantageous. The cockpit charts have proven to be useful tools when monitoring the performance of a telescreening service. Grader feedback showed high satisfaction with the quality assurance process.

Intracellular delivery of carbohydrates into mammalian cells through swelling-activated pathways

Volume changes of human T-lymphocytes (Jurkat line) exposed to hypotonic carbohydrate-substituted solutions of different composition and osmolality were studied by videomicroscopy. In 200 mOsm media the cells first swelled within 1-2 min and then underwent regulatory volume decrease (RVD) to their original isotonic volume within 10-15 min. RVD also occurred in strongly hypotonic 100 mOsm solutions of di- and trisaccharides (trehalose, sucrose, raffinose). In contrast to oligosaccharide media, 100 mOsm solutions of monomeric carbohydrates (glucose, galactose, inositol and sorbitol) inhibited RVD. The complex volumetric data were analyzed with a membrane transport model that allowed the estimation of the hydraulic conductivity and volume-dependent solute permeabilities. We found that under slightly hypotonic stress (200 mOsm) the cell membrane was impermeable to all carbohydrates studied here. Upon osmolality decrease to 100 mOsm, the membrane permeability to monomeric carbohydrates increased dramatically (apparently due to channel activation caused by extensive cell swelling), whereas oligosaccharide permeability remained very poor. The size-selectivity of the swelling-activated sugar permeation was confirmed by direct chromatographic measurements of intracellular sugars. The results of this study are of interest for biotechnology, where sugars and related compounds are increasingly being used as potential cryo- and lyoprotective agents for preservation of rare and valuable mammalian cells and tissues.

Stellenwert der Endoprothetik im Bereich der Handchirurgie

Alloarthroplasty has largely replaced traditional procedures in arthrosis of hip and knee joints. In contrast the role of alloarthroplasty in comparison to traditional procedures in hand surgery has been uncertain. To evaluate this question every registered hand surgery department (n=307) in Germany received a questionnaire requesting information on number and type of implanted prostheses and traditional procedures concerning the wrist joint, distal radioulnar joint (DRUJ), first carpometacarpal joint (CMC), metacarpal phalangeal joint (MP), interphalangeal joint (PIP), and preferred characteristics of the prostheses. Of the 307 hand surgery departments, 150 (57% of the hospitals and 42% of the visiting surgeons) participated in the inquiry. Per year, only 98 wrist prostheses were implanted (distributed among five different models) but 1534 traditional procedures were performed. The Sauve-Kapandji procedure was the most popular for the DRUJ and was performed 264 times per year. In comparison 24 hemiarthroplasties were implanted at the DRUJ. Trapezectomy remains the standard procedure for arthrosis of the first CMC joint (n=1399). The future importance of alloarthroplasty of the CMC joint is doubted by the majority of participating hand surgeons (90.3%). In contrast the majority (85.3/71.8%) is convinced that alloarthroplasty will be of importance for the MCP and PIP joints, respectively. Currently, the number of implanted prostheses is close to the number of traditional procedures performed at the MP joint. Irrespective of the joint involved, cementless anchorage is preferred as is the surface replacement anatomical design. The results confirm that alloarthroplasty in hand surgery is of minor importance. Thus, the role of alloarthroplasty differs depending on the joint involved. Traditional procedures except for the MP joint continue to be of major importance in hand surgery.

Synthesis and evaluation of (S)-2-(2-[18F]fluoroethoxy)-4-([3-methyl-1-(2-piperidin-1-yl-phenyl)-butyl-carbamoyl]-methyl)-benzoic acid ([18F]repaglinide): a promising radioligand for quantification of pancreatic beta-cell mass with positron emission tomography (PET)

18F-labeled non-sulfonylurea hypoglycemic agent (S)-2-(2-[(18)F]fluoroethoxy)-4-((3-methyl-1-(2-piperidin-1-yl-phenyl)-butylcarbamoyl)-methyl)-benzoic acid ([(18)F]repaglinide), a derivative of the sulfonylurea-receptor (SUR) ligand repaglinide, was synthesized as a potential tracer for the non-invasive investigation of the sulfonylurea 1 receptor status of pancreatic beta-cells by positron emission tomography (PET) in the context of type 1 and type 2 diabetes. [(18)F]Repaglinide could be obtained in an overall radiochemical yield (RCY) of 20% after 135 min with a radiochemical purity higher than 98% applying the secondary labeling precursor 2-[(18)F]fluoroethyltosylate. Specific activity was in the range of 50-60 GBq/micromol. Labeling was conducted by exchanging the ethoxy-moiety into a 2-[(18)F]fluoroethoxy group. To characterize the properties of fluorinated repaglinide, the affinity of the analogous non-radioactive (19)F-compound for binding to the human SUR1 isoform was assessed. [(19)F]Repaglinide induced a complete monophasic inhibition curve with a Hill coefficient close to 1 (1.03) yielding a dissociation constant (K(D)) of 134 nM. Biological activity was proven via insulin secretion experiments on isolated rat islets and was comparable to that of repaglinide. Finally, biodistribution of [(18)F]repaglinide was investigated in rats by measuring the concentration of the compound in different organs after i.v. injection. Pancreatic tissue displayed a stable accumulation of approximately 0.12% of the injected dose from 10 min to 30 min p.i. 50% of the radioactive tracer could be displaced by additional injection of unlabeled repaglinide, indicating that [(18)F]repaglinide might be suitable for in vivo investigation with PET.

A mycotic aneurysm of the ascending aorta and aortic arch induced by salmonella enteritidis

In very rare cases, salmonella infection may be associated with extra-intestinal manifestations. Of these, a mycotic aneurysm represents a life-threatening complication that is characterised by a high mortality rate. Prompt treatment with a combination of antibiotic therapy and surgical intervention is urgently required. We report on the case of a 60-year-old woman who presented with salmonella bacteraemia and the rare complication of an infected aneurysm of the ascending aorta and aortic arch.

Klinische Ergebnisse nach Sauv�-Kapandji-Operation in Abh�ngigkeit der Erkrankung

We present the results of a retrospective study on 56 patients who underwent the Sauve-Kapandji procedure for chronic disorders of the distal radioulnar joint (DRUJ). Outcome was assessed with special regard to the diagnosis. The average follow-up was 5.9 years (1-12 years). Patients were assessed for pain, range of motion of wrist and forearm, and radiological features. The DASH score and Mayo wrist score were used. The diagnosis had an influence on the outcome. Patients with primary arthrosis of the DRUJ demonstrated better results than patients with traumatic disorders. Patients with growth deficiency-related complaint of the DRUJ showed slightly inferior results after the Sauve-Kapandji procedure compared to all patients. Patients were free of pain or had pain only during heavy labor in 81% of cases; 95% of the patients rated the outcome as excellent or improved, but only 50% were free of symptoms on the operated side during heavy manual labor. Symptoms of ulnar impingement were found in 11%. Improvement in range of motion of wrist and forearm was significant. The postoperative DASH score was 24.2+/-22.5 and the Mayo wrist score was 76.1+/-17.6. Our results confirm the Sauve-Kapandji procedure to be a reliable salvage procedure resulting in high patient satisfaction and reliable improvement in range of motion. However, decreased grip strength on the affected side must be accepted to some extent. The diagnosis of a DRUJ disorder influences the outcome.

Feasibility of using the TOSCA telescreening procedures for diabetic retinopathy

AIMS

The TOSCA project was set up to establish a tele-ophthalmology service to screen for diabetic retinopathy (DR) in Europe. The aim of this study was to determine the feasibility of establishing telemedicine-based digital screening for detecting DR and to evaluate the satisfaction of both patients and healthcare professionals with the screening procedures used within the TOSCA project.

METHODS

The study was a non-randomized, multicentre study carried out in four different countries over a period of 3 months. Patients (n = 390) with diabetes aged > 12 years were included. Two digital retinal images per eye (macular and nasal) were taken and exported to a central server. Patients were asked to complete a questionnaire to assess satisfaction. Accredited graders carried out grading remotely and the results were reported back to the referring centre. Previously graded patient data chosen randomly to represent examples of both DR and no DR were also sent anonymously to the grading centre at a frequency of approximately every 10 patients.

RESULTS

Most (99%) of the images were assessable enabling a retinopathy grade to be assigned to the patient. Patients found the retinal photography procedures acceptable; only 6% in one centre would not recommend the procedure. Healthcare professionals (photographers and graders) were also satisfied with the overall procedures. The average time taken to grade each patient was approximately 5 min.

CONCLUSIONS

This study demonstrated that it is feasible to electronically transmit and grade retinal images remotely using the TOSCA process. Built-in quality assurance procedures proved acceptable.

Binding N2, N2H2, N2H4, and NH3 to transition-metal sulfur sites: modeling potential intermediates of biological N2 fixation

In the quest for low-molecular-weight metal sulfur complexes that bind nitrogenase-relevant small molecules and can serve as model complexes for nitrogenase, compounds with the [Ru(PiPr(3))('N(2)Me(2)S(2)')] fragment were found ('N(2)Me(2)S(2)'(2-)=1,2-ethanediamine-N,N'-dimethyl-N,N'-bis(2-benzenethiolate)(2-)). This fragment enabled the synthesis of a first series of chiral metal sulfur complexes, [Ru(L)(PiPr(3))('N(2)Me(2)S(2)')] with L=N(2), N(2)H(2), N(2)H(4), and NH(3), that meet the biological constraint of forming under mild conditions. The reaction of [Ru(NCCH(3))(PiPr(3))('N(2)Me(2)S(2)')] (1) with NH(3) gave the ammonia complex [Ru(NH(3))(PiPr(3))('N(2)Me(2)S(2)')] (4), which readily exchanged NH(3) for N(2) to yield the mononuclear dinitrogen complex [Ru(N(2))(PiPr(3))('N(2)Me(2)S(2)')] (2) in almost quantitative yield. Complex 2, obtained by this new efficient synthesis, was the starting material for the synthesis of dinuclear (R,R)- and (S,S)-[micro-N(2)[Ru(PiPr(3))('N(2)Me(2)S(2)')](2)] ((R,R)-/(S,S)-3). (Both 2 and 3 have been reported previously.) The as-yet inexplicable behavior of complex 3 to form also the R,S isomer in solution has been revealed by DFT calculations and (2)D NMR spectroscopy studies. The reaction of 1 or 2 with anhydrous hydrazine yielded the hydrazine complex [Ru(N(2)H(4))(PiPr(3))('N(2)Me(2)S(2)')] (6), which is a highly reactive intermediate. Disproportionation of 6 resulted in the formation of mononuclear diazene complexes, the ammonia complex 4, and finally the dinuclear diazene complex [micro-N(2)H(2)[Ru(PiPr(3))('N(2)Me(2)S(2)')](2)] (5). Dinuclear complex 5 could also be obtained directly in an independent synthesis from 1 and N(2)H(2), which was generated in situ by acidolysis of K(2)N(2)(CO(2))(2). Treatment of 6 with CH(2)Cl(2), however, formed a chloromethylated diazene species [[Ru(PiPr(3))('N(2)Me(2)S(2)')]-micro-N(2)H(2)[Ru(Cl)('N(2)Me(2)S(2)CH(2)Cl')]] (9) ('N(2)Me(2)S(2)CH(2)Cl'(2-) =1,2-ethanediamine-N,N'-dimethyl-N-(2-benzenethiolate)(1-)-N'-(2-benzenechloromethylthioether)(1-)]. The molecular structures of 4, 5, and 9 were determined by X-ray crystal structure analysis, and the labile N(2)H(4) complex 6 was characterized by NMR spectroscopy.