Klinische und radiologische Ergebnisse nach bipolarer Radiuskopfprothese

Background

Radial head arthroplasty is considered to be the treatment of choice in non-reconstructable radial head fractures in the acute fracture situation. Despite the promising short-term results in the current literature, replacement of the radial head remains controversially discussed as long-term results are still missing. In our study, we report our 7.8-year results after treatment with the bipolar radial head prosthesis of Judet.

Materials and methods

Between 1997 and 2004, 34 patients were treated with Judet??s bipolar radial head prosthesis in our department. After a mean of 94 months (range 15?C139), 28 of these 34 patients could be re-examined. While 20 patients were treated with radial head arthroplasty primarily in a fracture situation, 7 patients were treated secondarily after failure of fixation. One patient was treated for a tumor of the proximal radius.

Results

According to the Mayo Elbow Performance Score, 16 patients achieved an excellent, 10 patients a good, 1 patient a fair, and 1 patient a poor result. The mean Disabilities of the Arm, Shoulder and Hand Questionnaire (DASH) score was 12.0 (range 0?C50.1). There was no distinct difference between primary and secondary implantation in terms of the clinical outcome. The elbow flexion averaged 125° (range 100?C150°); the mean extension deficit was 20° (range 0?C60°). The mean pronation was 66° (range 0?C90°) with a mean supination of 67° (range 0?C90°). The most common complications were osteoarthritis of the ulnohumeral joint (n=18) and degenerative changes of the humeral capitellum with erosions (n=12). Finally, 3 patients suffered a dislocation after the surgical intervention, 1 patient had an infection, and 1 patient developed a radioulnar synostosis.

Conclusion

Despite major primary complications and the high incidence of radiographic signs of degenerative changes, mainly good clinical results were achieved after 7.8 years with Judet??s bipolar prosthesis.     

The impact of imaging speed of MR-guided punctures and interventions in static organs--a phantom study

Purpose

Verification of MR-guidance with image acquisitions slower than 1 image per second as it is inevitable for some interventions. Therefore, we quantified solely the effect of acquisition-time on the efficiency of MR-guided interventions in a static phantom study.

Materials and methods

We measured the duration, accuracy and error rate of simulated interventions for different acquisition-times using a simplified interventional setup. All measurements were performed in a 1.0 T open MRI scanner. Imaging was performed with a gradient-echo sequence (flipangle = 20°; TR/TE = 12/6 ms; voxelsize = 1 mm × 1 mm; slicethickness = 5 mm; FOV = 230 mm × 200 mm; acquisition-time = 1 s). Variable acquisition times were simulated with intermediate pauses of 0, 1, 2, 3, 4 and 5 s. The interventions were performed by a total of 20 volunteers including 7 experienced interventionalists.

Results

The mean duration of the intervention was 2 min. Significant differences between experienced and unexperienced volunteers were limited to the localization of the image plane and corrections made. The mean accuracy was 5.6 mm. The time to localize the image plane increased with deceleration of imaging from 24 s to 49 s. A similar increase was observed for the intervention time (55–108 s). A significant influence of the acquisition-time on durations and corrections was only found with acquisition-times greater than 4 s per image.

Conclusion

Even image rates of several seconds per image are sufficient enough for efficient interventions in static organs. Thus, the main attention has to be turned on the visibility of the needle when sequences are optimized for MR-guidance. The minimization of imaging speed is rather of secondary interest.     

Severe complications in a child with achondroplasia and two FGFR3 mutations on the same allele

We describe a unique case of achondroplasia with associated complications, including severe respiratory problems. Molecular analysis of the fibroblast growth factor receptor type 3 (FGFR3) gene in this patient showed the common p.G380R mutation and a second novel p.L377R mutation. An allele-specific PCR demonstrated that these mutations were on the same allele (cis). Both mutations were not present in the parents and appear to have occurred de novo. To our knowledge, this is the first report in the literature on an achondroplasia patient with two FGFR3 mutations on the same allele.     

Drayer's syndrome of mental retardation, microcephaly, short stature and absent phalanges is caused by a recurrent deletion of chromosome 15(q26.2-->qter)

We reevaluated a unique family with two sibs who had a presumed autosomal recessively inherited syndrome characterized by mental retardation, microcephaly, short stature and absent phalanges. This family was originally described by Drayer et al. in 1977. Using modern molecular techniques, we demonstrated that the syndrome is caused by the recurrence of an apparently de novo 15qter deletion of 5.8 Mb. Analysis of polymorphic markers revealed that the deletion was of maternal origin in both cases, indicating germline mosaicism in the clinically unaffected mother. This study demonstrates the possibility of parental mosaicism and the risk of recurrence in sibs for terminal subtelomeric deletions.     

Modulation der renalen Transmitter-Freisetzung durch präsynaptische Rezeptoren

Summary Renal sympathetic nerve varicosities possess a variety of receptors which when activated by appropriate agonists can modulate noradrenaline release at the local level of the kidney. Thus, activation of prejunctional ₁- and ₂-adrenoceptors, prostaglandin (PG), dopamine, adenosine and serotonin receptors inhibits, whereas activation of prejunctional ₂-adrenoceptors and angiotensin (A) II receptors enhances renal noradrenaline release. Moreover, neuronally released noradrenaline itself activates prejunctional inhibitory ₁- and ₂-adrenoceptors forming a negative feedback loop of its own release (autoinhibition). PGE₂ and adenosine locally formed in the kidney by renal nerve stimulation inhibits noradrenaline release through activation of their specific prejunctional receptor system (transjunctional inhibition).

     

Osteoporosis in Transplant Recipients

Osteoporosis is a frequent and severe complication of transplantation that substantially reduces the recipient's quality of life. However, strategies to prevent or to treat osteoporosis have as yet not been established. Determination of bone mass and density is the basis for interventions following transplantation. Therefore, bone mineral density should be measured in all patients awaiting transplantation to assess their individual risk of fracture. Prophylaxis should be considered in patients at high risk in view of the rapid initial bone loss after transplantation. Treatment of acute rejection with corticosteroids induces more bone loss than maintenance therapy with corticosteroids. Once manifest osteoporosis has occurred, treatment with a triple therapy consisting of calcium, vitamin D and either calcitonin or bisphosphonates is possible without negative effects on graft function. Therapy should be initiated according to the general guidelines for osteoporosis therapy, but several aspects specific for this patient group have to be considered. The present recommendations for the management of osteoporosis after transplantation need to be proven by further intervention studies.     

A new type of perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) in active ulcerative colitis but not in Crohn's disease

Sera of 64 patients with chronic inflammatory bowel disease (IBD) were screened for antibodies against neutrophil cytoplasmic antigens (ANCA) using an indirect immunofluorescence technique on ethanol-fixed human neutrophil granulocytes. 20 of 34 sera (59%) from patients with ulcerative colitis (UC) produced a fine-granular and perinuclear ANCA staining pattern (p-ANCA) clearly different from the typical diffuse and granular cytoplasmic ANCA fluorescence (c-ANCA, synonym ACPA) seen in active Wegener's granulomatosis (WG). The majority of the 20 p-ANCA positive UC patients had a high inflammatory disease activity. Among the 14 p-ANCA negative UC patients nine were without steroids; five of them had active disease, two were inactive and two had previously undergone colectomy. The remaining five patients still had active disease but received steroids for more than 4 weeks. Only 3 of the 30 sera from patients with Crohn's disease (CD) showed positive p-ANCA reactions. To narrow the specificity of the p-ANCA reaction all 64 sera were tested by ELISA for antibodies against anti-proteinase-3 (WG specific) and on HEp-2 cells for antinuclear (ANA) and anticytoplasmic antibodies. Ten p-ANCA positive UC sera were also tested in a myeloperoxidase ELISA. Only one UC serum reacted positively in the proteinase-3-ELISA and another one produced a weakly positive anti-nucleolar ANA fluorescence on HEp-2 cells. None of the tested sera reacted with myeloperoxidase suggesting that the p-ANCA staining pattern of granulocytes is not restricted to anti-myeloperoxidase antibodies as reported in the literature.(ABSTRACT TRUNCATED AT 250 WORDS)