Agreement of Experiment and Theory on the Single Ionization of Helium by Fast Proton Impact.

Even though the study of ion-atom collisions is a mature field of atomic physics, large discrepancies between experiment and theoretical calculations are still common. Here we present experimental results with high momentum resolution on the single ionization of helium induced by 1-MeV protons, and we compare these to theoretical calculations. The overall agreement is strikingly good, and even the first Born approximation yields good agreement between theory and experiment. This has been expected for several decades, but so far has not been accomplished. The influence of projectile coherence effects on the measured data is briefly discussed in terms of an ongoing dispute on the existence of nodal structures in the electron angular emission distributions.

Fibromuscular dysplasia mimicking Crohn's disease over a period of 23 years.

Rare diseases with similar clinical presentation as more frequent gastrointestinal disorders might be challenging in the diagnostic and therapeutic management. In this case we report on a 47-year-old woman who was thought to suffer from Crohn's disease. Symptoms, macroscopic and histological aspects of the gastrointestinal tract, treatment response and clinical course had encouraged the wrong diagnosis over a period of 23 years. After the patient died in the context of a sudden clinical deterioration, fibromuscular dysplasia of the aorta was finally unmasked by post-mortem examination as underlying cause of all symptoms attributed to Crohn's disease. Re-evaluation of former diagnostic procedures revealed subtle aspects of fibromuscular dysplasia, even in biopsy samples from 23 years ago. This first case report of fibromuscular dysplasia of the aorta documents a rare pitfall in the diagnostic workup of a frequent clinical presentation in gastroenterology.

[Pain therapy using stimulating catheters after total knee arthroplasty]. / Schmerztherapie mit Stimulationskathetern bei Kniegelenkersatz.

BACKGROUND: Epidural analgesia and continuous femoral nerve blocks are often used for pain therapy after total knee arthroplasty. The additional use of a continuous sciatic nerve block is controversially discussed. To avoid the problem of inaccurate placement a stimulating catheter may be useful. The aim of this study was to compare the effectiveness of a continuous femoral nerve block with an additional continuous sciatic nerve block for improved functional recovery and pain relief. MATERIAL AND METHODS: An open randomized prospective controlled study was carried out with 54 patients to receive either a stimulating catheter placed in the femoral nerve sheath or two stimulating catheters placed in the femoral and in the sciatic nerve sheath or an epidural analgesia. Pain was recorded with the visual analogue scale at rest and with passive motion of the knee during the first 3 postoperative days. The angle of nearly pain-free bending of the knee, side effects and opioid consumption were recorded. RESULTS: The reported pain scores and opioid consumption did not differ significantly between the groups. However, functional recovery up to the third postoperative day was significantly worse in the femoral catheter group. CONCLUSION: Using stimulating catheters for pain therapy the three methods are largely comparable and other parameters should be used for individual selection.

[Halo-fixator vest--indications and complications]. / Halo-Fixateur - Indikationen und Komplikationen.

Over the period between 06/00 and 03/03, 41 patients with different injuries of the upper cervical spine were treated by a halo fixator and were statistically recorded. The collective showed different injury patterns, 2 fractures of occiput condyles (5%), 3 Jefferson fractures (7%), 1 combined injury of the odontoid process and an atlas fracture (2%), 32 odontoid fractures (78%), 2 hanged-man-fractures Typ Effendi II (5%) and one case of pathologic fractures from the 2. to the 4. cervical vertebral body based on a plasmocytoma (2%). 31 of 41 patients could be examined for a follow up; 40 complete medical histories were well documented and could be analysed. As complications we had screw loosening in 6 cases (15%), a complete tear out of screws in 2 cases (5%). One patient took the halo away by himself two times, so after the second time surgical stabilisation was performed (2,5%). One case of intracranial penetration of a screw happened after the patient fell down in an accident with the halo (2,5%). Infection of the screw pins appeared in 4 cases (10%) and we had 2 cases of skin necrosis (5%). A second reduction after redisplacement was necessary in 8 cases (20%). 23 patients suffered from pain at the insertion of the screws (75%) and 18 patients complained of pressure in the head (58%). On the question of the comfort of this kind of therapy answered 18 patients with "intolerable" (58%), 10 patients with middle (32%) and 3 patients with tolerable (10%). Despite of the large number of different complications and the miscomfort of a halo fixator we think that there are still indications for treatment of special injuries of the upper cervical spine with a halo fixator. One important aspect is the lack of adequate alternatives even with regard to the biomechanical stability.

Clinical and radiological findings after different treatment of odontoid fractures type Anderson II and III.

PURPOSE OF THE STUDY: In the period from 06/00 to 08/02, 31 patients with odontoid fractures type Anderson II and III were treated and stastically recorded. 25 patients were followed up; the progess of 24, documented in detail radiographically, were evaluated independently by a traumatologist and by a radiologist. The usual time of immobilization when treating odontoid fractures type Anderson type II and III with the halo-fixator is 12 weeks. For this 12 weeks that it is worn, objective assessment of bone healing is performed radiographically and the results critically considered in terms of the length of time that the halo-fixator should be worn and whether this duration should be altered on the basis of the clinical and radiological results obtained. MATERIALS AND METHODS: 16 patients with an odontoid fracture type Anderson type II were treated partly with a halo-fixator and partly by additional operative stabilization. 15 patients with a type III fracture were treated in a halo over 12 weeks. At the time of the accident the patients to be treated had to have conventional radiographic examination and a CT scan as well as a position check following reduction. After 4, 8 and 12 weeks radiographic and CT investigation was repeated. These findings were evaluated independently by a surgeon and a radiologist. The clinical follow-up was carried out using the VAS Score and, in addition, the general activity level before and after the accident was recorded in a similar way on the Tegner/Lysholm subjective activity score. RESULTS: In most cases, according to the CT scan, the osseous bridging decreased again between the 8th and 12th weeks, as defined by resorption zones seen during the fracture healing period. Radiological evidence of complete osseous bridging was only seen after 12 weeks in three cases. CONCLUSION: Conventional radiography does not seem to us to be the most suitable technical means to evaluate osseous healing in odontoid fractures. The CT is more reliable for this. According to our radiological results, osseous healing of different types of odontoid fractures takes more than 12 weeks. Despite of its known complications, the halo fixator is still a good instrument for the treatment of odontoid fractures.

[Spondylocostal dysostosis: a rare genetic disease]. / Dysostose spondylo-costale: une maladie génétique rare.

Spondylocostal dysostoses represent a group of very rare genetic disorders, characterised by vertebral and costal segmentation defects, sometimes accompanied by visceral malformations. The major gene involved is DLL3, on chromosome 19. A mutation may lead to a somitogenesis defect, with segmentation defect of axial skeleton and deformations. Depending on the nature of the mutation of DLL3, spondylocostal dysostosis is transmitted as an autosomal dominant (less severe) or autosomal recessive trait (often more severe, but non lethal). Spondylocostal dysostoses must not to be confused with the Jarcho-Levin spondylothoracic dysostosis, a severe, autosomal recessive syndrome. Its most typical aspect is the crab-like appearance of the rib cage leading to major respiratory disorders. Death, due to respiratory insufficiency, usually occurs before the age of two, most often during the first few months. At this time, guidelines for treatment do not exist. We report a case of spondylocostal dysosotosis in a patient born to consanguineous turkish parents, and review the clinical and genetic data on that group of skeletal disorders.

[Treatment of perivascular extravasation of cytostatic agents]. / Paravenöse Zytostatikainjektion: Prophylaxe und Sofortmassnahmen im Notfall.

In the intravenous administration of cytostatic drugs, top priority is given to preventive measures, and to immediate countermeasures in the event of an accidental paravenous injection. In contrast to earlier recommendations, the use of antidotes has been minimized. Only those with proven efficacy and no tissue toxic potential are to be used. The intradermal application of sodium bicarbonate and sodium thiosulfate, and the subcutaneous administration of glucocorticoids are no longer applicable. As a specific antidote in the case of anthracycline, topical dimethylsulfoxide (DMSO) is used, and for perivascular injection of vinca alkaloid, subcutaneous hyaluronidase is administered.

Fracture treatment in the elderly.

With an ever increasing percentage of elderly people among the population fracture management in the aged is of increasing importance in the field of traumatology, since people between the ages of 60 and 80 will constitute the largest subpopulation by 2030. Due to relevant interindividual differences concerning physical constitution and comorbidity this group resembles an extremely inhomogenic population of patients. Discrepancies between biologic and chronologic age make a careful selection of suitable therapeutic strategies individually adapted to a single patient's situation necessary. For the biologically younger patient with good compliance conservative treatment or minimal osteosynthetic procedures requiring partial weight bearing might constitute a reasonable and appropriate therapeutic option whereas for biologically older patients with relevant co-morbidity early mobilisation with short hospitalisation periods is of the highest priority. This is why in these cases osteosynthetic procedures with implants that allow full weight bearing initially after surgery should be preferred. Even though in advanced age there is an increasing risk of fractures in general -- due to increasing incidence of falls and decreasing bone mineral density -- the majority of fractures in elderly is located in the proximal femur, the proximal humerus and the distal radius. Therefore, therapy of fractures in these typical locations shall in recognition of the particular characteristics of the advanced age be displayed in this article.