A closer look at right ventricular 3D volume quantification by transthoracic echocardiography and cardiac MRI.

AIM: To compare right ventricular (RV) volumetry using state-of-the-art three-dimensional (3D) transthoracic echocardiography (3DE) and cardiac magnetic resonance imaging (CMR) near-simultaneously in a clinical setting. MATERIALS AND METHODS: Forty-seven consecutive patients received comprehensive echocardiography including 3DE within 30 minutes of CMR. RV volumetry was performed offline with semi-automated 3D endocardial border tracing as well as manual delineation of the compacted myocardium in short-axis views by CMR. RESULTS: Forty-two examinations (89%) could be analysed offline by 3D RV reconstruction. Mean RV volumes assessed by CMR and 3DE were 215±63 and 127±42 ml for end-diastole (RV-EDV), as well as 110±43 and 62±27 ml for end-systole (RV-ESV). RV-EDV, RV-ESV, and RV stroke volume measured by 3DE were significantly lower than RV volumetry by CMR. Mean bias were -88, -48, and -41 ml, respectively. Mean RV ejection fraction (-EF) showed a non-significant deviation of +2% between 3DE and CMR and the correlation coefficient was r=0.58 for RV-EF. CONCLUSION: RV-EF can be assessed reliably using transthoracic 3DE in patients with good image quality; however, absolute RV volumes measured by 3DE show a systematic deviation to CMR volumetry that has been previously neglected and requires careful interpretation regarding anatomical cardiac imaging.

Prospective randomized controlled trial in the treatment of lateral epicondylitis with a new dynamic wrist orthosis.

BACKGROUND: In the treatment of lateral epicondylitis (LE), the role of a new dynamic wrist orthosis is unclear. PATIENTS AND METHODS: Patients suffering from a LE longer than 3 months were multicentrically and prospectively randomized into a physiotherapeutic group (PT group) and in a physiotherapy group plus wrist orthosis (PT + O group). Physiotherapy consisted of daily eccentric strengthening exercises under initial professional supervision. Inclusion criteria were a Placzek score greater than 4. Exclusion criteria were previous surgery, rheumatic arthritis, elbow instability, radicular symptoms, higher-grade extensor tendon rupture, or cervical osteoarthritis. The clinical evaluation was performed after 12 weeks and 12 months. The Patient-Rated Tennis Elbow Evaluation (PRTEE) scale, Placzek Score, the pain rating (VAS), range of motion and the Subjective Elbow Score were evaluated. RESULTS: Of the initially 61 patients, 31 were followed up after 12 weeks and 22 after 12 months. Twenty-nine patients (43%) were male, the mean age was 46, and 44 patients (66%) had the right elbow involved. At 12 weeks, there was a pain reduction on the VAS in both groups (PT + O: 6.5-3.7 [p = .001]; PT: 4.7-4.1 [p = .468]), albeit it was only significant for the PT + O group. At 12 months, reduction was significant in both groups (PT + O: 1.1 [p = .000]; PT: 1.3 [p = .000]). The painless maximum hand strength in kg improved in both groups significant after 3 and 12 months. The Placzek score was reduced from 8.25 to 3.5 [p = .001] after 12 weeks for the PT + O group and from 8.1 to 3.8 [p = .000] in the PT group, as well as after 12 months in the PT + O group to 0 [p = .000] and in the PT group to 2.0 [p = .000]. The PRTEE improved in both groups after 12 weeks (PT + O: 52.8--31.3 [p = .002]; PT: 48.6-37.6 [p = .185]) and 12 months (PT + O: 16.15 [p = .000]; PT: 16.6 [p = .000]), although the reduction at 12 weeks was not significant for the PT group. CONCLUSION: The elbow orthosis appears to accelerate the healing process with respect to the PRTEE and pain on the VAS (12 weeks follow-up), although there is an adjustment after 12 months in both groups and a significant improvement of symptoms is achieved in all endpoints.

The effect of ovine peripheral blood mononuclear cells on Haemonchus contortus larval morbidity in vitro.

The objective of this study was to determine the effects of peripheral blood mononuclear cells (PBMC), derived from parasite-resistant St. Croix (STC) hair sheep and parasite-susceptible Suffolk (SUF) sheep, on Haemonchus contortus L3 stage larval death in vitro, with or without autologous serum. Larval morbidity was quantified by measuring larval ATP concentration following incubation with PBMC. Larvae exposed to either STC- or SUF-derived PBMC had lower ATP than live larvae (0.12 µmol/L ATP and 0.16 µmol/L ATP vs 0.27 µmol/L ATP, respectively) (P<.001) and greater ATP of dead larvae (0.03 µmol/L ATP) (P<.001). Breed differences were observed with addition of autologous serum. Larvae exposed to SUF-derived PBMC with autologous serum were not significantly different from live larval ATP. STC-derived serum did not significantly reduce larval ATP compared to PBMC alone (0.11 µmol/L ATP), but was significantly reduced compared to live larvae (0.22 µmol/L ATP) and SUF-derived PBMC with autologous serum (0.23 µmol/L ATP) (P<.001). These data indicate that a cellular response alone is capable of significantly reducing larval ATP in a breed-independent manner. However, addition of serum to SUF-PBMC failed to reduce larval ATP, indicating breed-dependent humoral response to H. contortus.

Serum-mediated Haemonchus contortus larval aggregation differs by larval stage and is enhanced by complement.

The objectives of this study were to measure Haemonchus contortus larval aggregation by complement/antibody complexes, determine effect of breed resistance and infection status and determine the effect of larval maturation on larval aggregation in vitro. Larval binding assays were performed on H. contortus L3, exsheathed L3 and L4 incubated with serum from either parasite naïve or H. contortus primed St. Croix (resistant) and Suffolk (susceptible) lambs. No differences in L3 aggregation were observed between serum from either breed or infection status. Exsheathed L3 (60%) and L4 (42%) aggregation by primed Suffolk serum was significantly reduced compared with L3 (80%, P<.001). Removal of either complement or antibody effectively eliminated L3 aggregation (P<.001). Combination of antibody-depleted and complement-inactivated serum restored L3 aggregation to levels consistent with unprocessed serum, supporting a role for antibody and complement in aggregation (P<.001). Use of fluorescence-labelled anti-sheep IgG antibody allowed documentation of IgG bound to serum complexes within L3 masses and was present only in larvae incubated with normal serum, and complement- and antibody-depleted serum combination. These data indicate that complement/antibody complexes inhibit larval motility through larval aggregation which may be critical in early larval clearance of H. contortus.

[Clinical classification and initial diagnosis of pulmonary hypertension: recommendations of the Cologne Consensus Conference 2016]. / Klinische Klassifikation der pulmonalen Hypertonie und initiale Diagnostik: Empfehlungen der Kölner Konsensus Konferenz 2016.

The 2015 European Guidelines on Diagnosis and Treatment of Pulmonary Hypertension are also valid for Germany. The guidelines contain detailed information about the clinical classification and diagnosis of pulmonary hypertension, and furthermore provide novel recommendations for risk stratification and follow-up assessments. However, the practical implementation of the European Guidelines in Germany requires the consideration of several country-specific issues and already existing novel data. This requires a detailed commentary to the guidelines, and in some aspects an update already appears necessary. In June 2016, a Consensus Conference organized by the PH working groups of the German Society of Cardiology (DGK), the German Society of Respiratory Medicine (DGP) and the German Society of Pediatric Cardiology (DGPK) was held in Cologne, Germany. This conference aimed to solve practical and controversial issues surrounding the implementation of the European Guidelines in Germany. To this end, a number of working groups was initiated, one of which was specifically dedicated to the clinical classification and initial diagnosis of PH. This article summarizes the results and recommendations of this working group.

Combined arthroscopic tenodesis of the long head of biceps and rotator cuff repair in antero-superior cuff tears.

PURPOSE AND HYPOTHESIS: This study evaluates the functional and cosmetic results following fixation of the long head of the biceps (LHB) tendon at the antero-medial footprint anchor of a rotator cuff reconstruction, using the "lasso-loop" technique. METHODS: 39 patients with a mean age of 62 years with a rotator cuff tear and associated lesion of the LHB tendon were included in this study. Besides rotator cuff repair in an arthroscopic anchor technique, all patients received additional LHB tenodeses using the lasso-loop technique. Clinical follow-up consisted of the Constant score (CS), LHB score, DASH score, and WORC index. Relevant sub-items, such as elbow flexion strength and cosmesis, were compared to the contralateral arm. RESULTS: At an average follow-up of 22 months (11-39 months), the CS resulted in an average of 81 points. The biceps-specific LHB score showed a mean value of 89 points. The analysis of the DASH score showed an average of 16.9 points and the analysis of the WORC index showed an average result of 79.7 %. Distalization of the biceps muscle was objectively in three cases (7.7 %) (as observed by the examiner) and subjectively in one of those cases (as noted by the patient). There was a loss in elbow flexion strength compared to the contralateral side; however, this loss was not statistically significant and not associated with clinical apparent re-tear or insufficiency of the tenodesis. DISCUSSION: The arthroscopic lasso-loop tenodesis of the LHB tendon is a time and cost-efficient technique. No additional anchor is needed when included in the rotator cuff repair. Functional and cosmetical results as well as results from the biceps-specific LHB score were good to excellent. The loss in elbow flexion strength is most likely associated with concomitant rotator cuff lesion. CONCLUSION: The lasso-loop fixation technique of the LHB tendon using the antero-medial footprint anchor in rotator cuff tears is a reliable and cost-efficient procedure. LEVEL OF EVIDENCE: III.

Effect of early grain feeding of beef steers on postabsorptive metabolism.

The objective of this study was to determine the effect of early weaning followed by a period of high-grain feeding on plasma acetate kinetics and signaling protein phosphorylation in LM tissue of growing steers. We hypothesized that early grain feeding would result in altered cell signaling and acetate use to support observed improvements in carcass gain and marbling. Fall-born Angus × Simmental steers were weaned at 106 ± 4 d of age (early weaned [EW]; n = 6) and fed a high-grain diet for 148 d or remained with their dams (normal weaned [NW]; n = 6) on pasture until weaning at 251 ± 5 d of age. Both treatments were subsequently combined and grazed on mixed summer pasture to 394 ± 5 d of age followed by a feedlot ration until harvest at 513 ± 5 d of age. Longissimus muscle tissue biopsies were collected at 253 ± 5 and 394 ± 5 d of age and at harvest. Total and phosphorylated forms of 5' adenosine monophosphate-activated protein kinase (AMPK) and downstream proteins of the mammalian target of rapamycin signaling pathway were determined by western blotting. Eight steers were used to assess acetate clearance at different age points via a bolus infusion of acetate (4 mmol/kg of BW). Early weaned steers had greater (P < 0.05) ADG than NW steers during the early grain feeding period. Phosphorylated to total ratios of ribosomal protein S6 (rpS6) and ribosomal protein S6 kinase 1 (S6K1) were significantly different during the early grain feeding period. Phosphorylated to total ratios of S6K1, rpS6, acetyl-CoA carboxylase, and 4E binding protein 1 and the absolute amount of phosphorylated AMPK were correlated with ADG, explaining 46% of the variance. Acetate clearance rates were less (P < 0.05) and synthesis rates were greater (P = 0.06) in EW steers during early grain feeding. Acetate synthesis rates were also greater (P < 0.05) in NW steers at harvest, suggesting a permanent shift in the gut microflora or gut function in response to the treatment. Neither treatment nor acetate infusion significantly affected plasma glucose or insulin concentrations. Plasma ß-hydroxybutyric acid concentrations increased with acetate infusion (P < 0.05). Based on these results, altered cell signaling during the early grain feeding period likely mediated increased protein deposition, leading to increased carcass weights, but observed changes in acetate appearance and clearance rates do not appear to explain the observed differences in intramuscular fat deposition during the terminal feeding period.

Early metabolic imprinting events increase marbling scores in fed cattle.

Early weaning of calves to a high concentrate diet results in greater fat deposition and suggests early postnatal metabolic imprinting events may be exploited as a management tool to improve cattle value. Our objective was to implement a short, high energy dietary intervention before a typical grazing period to manipulate intramuscular fat deposition in finishing cattle. Fall-born, Angus-sired steer calves (n = 24) were stratified by sire and randomly assigned to normal weaned (NW) or metabolic-imprinted (MIP) treatments. At 105 ± 6d (135kg), MIP calves were transitioned to a diet containing 20% CP and 1.26 Mcal/kg NEg. Metabolic-imprinted calves were fed ad libitum as a group. Normal weaned calves remained on their dam until 253 ± 6 d of age. At this time, treatment groups were combined and grazed for 156 d on a mixed summer pasture. Following the grazing phase, steers were adapted to a corn silage-based feedlot diet and performance was monitored on 28-d intervals. Calves were staged for harvest based on backfat endpoint (target 1.0 to 1.2 cm). Metabolic-imprinted calves were heavier (P < 0.05) than NW calves (341 vs. 265 ± 4.2 kg) at normal weaning age. During the grazing phase, NW steers gained more weight than (P < 0.05) MIP steers (0.69 vs. 0.35 ± 0.03 kg/d). Feedlot performance and USDA yield grade were similar (P > 0.20) between treatments. However, MIP steers produced heavier (P < 0.05) carcasses (564 vs. 524 ± 5.6 kg) with higher (P < 0.001) marbling scores (645 vs. 517 ± 23). Therefore, calves consuming a high concentrate diet for 148 d after early weaning produced higher quality carcasses. This suggests early weaning and feeding a high concentrate before grazing is a viable strategy to increase marbling deposition compared with a traditional production system.

Evaluation of an oral health promotion program at the time of birth on dental caries in 5-year-old children in Vorarlberg, Austria.

OBJECTIVES: The aim of this study was to evaluate the effect of an early oral health promotion program (OHPP) on oral health of 5-year-old children in Austria by providing new mothers with dental health counseling. METHODS: Qualified dental health educators visited all mothers at time after birth in regional hospitals in Vorarlberg and counseled them regarding the oral health of their children as a one-off intervention. Mothers were given comprehensive oral hygiene instructions for their children and themselves (daily use of fluoride toothpaste, restoration of own caries lesions), which included practical tooth brush training and dietary counseling by the use of brief motivational interviewing and anticipatory guidance approaches. After 5 years, a case-cohort study was conducted to evaluate the program with annual dental check-ups of 471 children and a parent survey. Dental caries was scored using WHO diagnostic criteria at dentine level without radiography. To compare oral health parameters (dmfs/dmft, care index), children were allocated to intervention and control group and matched on basis of age, sex, ethnicity, and socio-economic status (SES) and analyzed statistically. RESULTS: Children whose mothers participated in the OHPP showed significantly lower caries prevalence and experience (33.2%; 3.2 ± 7.4 d3-4 mfs/1.5 ± 2.5 d3-4 mft) than children whose mothers did not participate (42.6%; 5.2 ± 6.4 d3-4 mfs/2.4 ± 4.1 d3-4 mft). Bivariate analysis showed that ethnicity, SES, age at which toothbrushing started, supervision of toothbrushing, use of fluoride salt, and use of fluoride toothpaste were significantly related to d3-4 mft. CONCLUSIONS: The OHPP was an effective community-based preventive approach for improving oral health in preschool children.

[Reverse shoulder arthroplasty for fracture sequelae]. / Inverse Schulterendoprothetik bei Frakturfolgezuständen.

Posttraumatic fracture sequelae of the proximal humerus represent an extremely heterogeneous pathology. In severe cases they are often associated with marked soft tissue scarring, osseous defects and insufficiency of the rotator cuff, resulting in a static instability of the humeral head. The aim of this article is to demonstrate the possibilities and early results of reverse shoulder arthroplasty for the operative management of this complex injury pattern.

Arthroscopic refixation of a combined fracture of the greater and lesser tuberosity of the proximal humerus.

UNLABELLED: Combined fractures of the greater and the lesser tuberosity are very rare injuries. This is a case report on arthroscopic treatment using suture anchors and one distal fixation screw. Clinical and radiographic follow-up showed recovery of active motion and consolidation of the fragments in anatomic positions. LEVEL OF EVIDENCE: V.

Effect of ß-tricalcium phosphate coated with zoledronic acid on human osteoblasts and human osteoclasts in vitro.

The combination of a bone graft material with bisphosphonates (BPs) might be advantageous for an optimal balance of material resorption and stimulation of bone formation. This study investigated the effect of ß-tricalcium phosphate (ß-TCP) bone grafts coated with zoledronic acid (ZOL) on osteoblast-like cells and osteoclast-like cells (OLC). As a drug carrier, the polymer poly(D,L-lactide) was used and three different concentrations of ZOL were tested. ß-TCP coated with ZOL stimulated the production of osteocalcin (OC), osteoprotegerin, and sRANKL in osteoblast-like cells. The polymer coating alone caused a significant increase in collagen type 1 and OC production. OLC viability was inhibited and the tartrate-resistant acidic phosphatase isoform-5b was significantly decreased after cultivation on polymer-coated ß-TCP for 12 days. The three different concentrations of ZOL decreased cell viability and no TRAPiso-5b was detectable, indicating a strong reduction of the TRAPiso-5b after 12 days in culture. After 21 days in culture, only the higher ZOL concentrations significantly reduced cell viability and TRAPiso-5b. The results of this study show that coating of ß-TCP with ZOL has stimulating effects on osteoblast-like cells. Additionally, an inhibition of osteoclasts was seen. The combination of this bone grafting material with BPs might, therefore, be effective in the treatment of large bone defects.

Using clinically approved cyclophosphamide regimens to control the humoral immune response to oncolytic viruses.

Oncolytic viruses can be neutralized in the bloodstream by antiviral antibodies whose titers increase progressively with each exposure, resulting in faster virus inactivation and further reductions in efficacy with each successive dose. A single dose of cyclophosphamide (CPA) at 370 mg m(-2) was not sufficient to control the primary antiviral immune responses in mice, squirrel monkeys and humans. We therefore tested clinically approved multidose CPA regimens, which are known to kill proliferating lymphocytes, to determine if more intensive CPA therapy can more effectively suppress antiviral antibody responses during virotherapy. In virus-susceptible mice, primary antibody responses to intravenously (i.v.) administered oncolytic measles virus (MV) or vesicular stomatitis virus (VSV) were partially or completely suppressed, respectively, by oral (1 mg × 8 days) or systemic (3 mg × 4 days) CPA regimens initiated 1 day before virus. When MV- or VSV-immune mice were re-challenged with the respective viruses and concurrently treated with four daily systemic doses of CPA, their anamnestic antibody responses were completely suppressed and antiviral antibody titers fell significantly below pre-booster levels. We conclude that the CPA regimen of four daily doses at 370 mg m(-2) should be evaluated clinically with i.v. virotherapy to control the antiviral antibody response and facilitate effective repeat dosing.

Effect of a novel nonviral gene delivery of BMP-2 on bone healing.

BACKGROUND: Gene therapeutic drug delivery approaches have been introduced to improve the efficiency of growth factors at the site of interest. This study investigated the efficacy and safety of a new nonviral copolymer-protected gene vector (COPROG) for the stimulation of bone healing. METHODS: In vitro, rat osteoblasts were transfected with COPROG + luciferase plasmid or COPROG + hBMP-2 plasmid. In vivo, rat tibial fractures were intramedullary stabilized with uncoated versus COPROG+hBMP-2-plasmid-coated titanium K-wires. The tibiae were prepared for biomechanical and histological analyses at days 28 and 42 and for transfection/safety study at days 2, 4, 7, 28, and 42. RESULTS: In vitro results showed luciferase expression until day 21, and hBMP-2-protein was measured from day 2 - day 10. In vivo, the local application of hBMP-2-plasmid showed a significantly higher maximum load after 42 days compared to that in the control. The histomorphometric analysis revealed a significantly less mineralized periosteal callus area in the BMP-2 group compared to the control at day 28. The rt-PCR showed no systemic biodistribution of luciferase RNA. CONCLUSION: A positive effect on fracture healing by nonviral BMP-2 plasmid application from COPROG-coated implants could be shown in this study; however, the effect of the vector may be improved with higher plasmid concentrations. Transfection showed no biodistribution to distant organs and was considered to be safe.

Influence of age on the cell biological characteristics and the stimulation potential of male human tenocyte-like cells.

The incidence of rotator cuff tears and recurrent defects positively correlate with patient age. However, this observation has never been analysed at the cellular level. The present study aims to better understand this correlation by investigating cellular characteristics of rotator cuff tenocytes of different age groups. Additionally, previous studies reported on stimulating effects of Bone Morphogenetic Protein (BMP) -2 and BMP-7 on tenocytes. Thus, the second aim was to investigate, whether the stimulation potential of tenocytes demonstrates age-related differences. Tenocyte-like cells from supraspinatus tendons of young and aged patients were analysed for the following cell biological characteristics: cell density, cell growth, marker expression, collagen-I protein synthesis, stem cell phenotype, potential for multipotent differentiation and self-renewal. To analyse the stimulation potential, cells were treated with BMP-2 and BMP-7 in 2D-/3D-cultures. Measured parameters included cell activity, marker expression and collagen-I protein synthesis. An effect of age was seen for cell growth and stem cell potential but not on extracellular matrix level. Cells from both groups responded to BMP-7 by increasing cell activity, collagen-I expression and protein synthesis. BMP-2 led to smaller increases in these parameters when compared to BMP-7. In general, 3D-cultivation improved the stimulation compared to 2D-culture. The cell biological characteristics of tenocyte-like cells, considered important for successful restoration of the tendon-bone unit, were inferior in elderly donors. This may help explain higher rates of recurrent defects seen in elderly patients. Regarding the stimulation potential, on a cellular level young and aged patients may benefit from biological augmentation with BMPs.

MR imaging findings in flexed abducted supinated (FABS) position and clinical presentation following refixation of distal biceps tendon rupture using bioabsorbable suture anchors.

PURPOSE: To correlate MRI findings after suture anchor repair of distal biceps tendons with symptoms. MATERIALS AND METHODS: 24 men with 25 distal biceps tendon ruptures (one bilateral) treated with suture anchor repair were retrospectively included. Follow-up after a mean of 31 months (range, 12-74) included clinical examination and MRI. The pain level and flexion strength compared to the uninvolved arm were recorded. MRI was performed at 1.5 T obtaining FABS position images (both elbows in 7 patients) and evaluated for artifacts, signal abnormalities, and rerupture by two experienced readers in consensus and blinded to symptoms. Pain and loss of flexion strength>20% were tested against MRI findings as dichotomous data using Fisher's exact chi-square tests (p<0.05). Crosssectional areas of operated and uninvolved tendons were measured and evaluated with the Wilcoxon signed rank test (p<0.05). RESULTS: FABS views enabled good evaluation in 96% of tendons. Rerupture was present in 3 of 25 elbows. Tendinous signal increase was seen in 59% of intact tendons. We found activity-related pain or pain at rest in 32% and a loss of flexion strength in 27 % of these cases. Testing revealed no significant correlation for any of the MRI features with any of the clinical parameters (p>0.05). There was a 2.7-fold mean increase of the tendon cross-sectional area on the repaired side compared to the uninvolved contralateral tendon (p=0.02). CONCLUSION: We found good MRI visualization of postoperative tendons, but no correlation between symptoms and MRI signal abnormalities or rerupture. The increase in caliber of the repaired tendon might promote an impingement in pronation.

Uncoupling of sexual reproduction from homologous recombination in homozygous Oenothera species.

Salient features of the first meiotic division are independent segregation of chromosomes and homologous recombination (HR). In non-sexually reproducing, homozygous species studied to date HR is absent. In this study, we constructed the first linkage maps of homozygous, bivalent-forming Oenothera species and provide evidence that HR was exclusively confined to the chromosome ends of all linkage groups in our population. Co-segregation of complementary DNA-based markers with the major group of AFLP markers indicates that HR has only a minor role in generating genetic diversity of this taxon despite its efficient adaptation capability. Uneven chromosome condensation during meiosis in Oenothera may account for restriction of HR. The use of plants with ancient chromosomal arm arrangement demonstrates that limitation of HR occurred before and independent from species hybridizations and reciprocal translocations of chromosome arms-a phenomenon, which is widespread in the genus. We propose that consecutive loss of HR favored the evolution of reciprocal translocations, beneficial superlinkage groups and ultimately permanent translocation heterozygosity.

[Bony avulsions of the rotator cuff : Arthroscopic concepts]. / Knöcherne Rotatorenmanschettenausrisse : Arthroskopische Konzepte.

Bony avulsions of the rotator cuff and isolated greater or lesser tuberosity fractures are rare injuries and a clear consensus regarding classification and therapy does not yet exist. Conservative therapy is limited, especially in injuries with displaced fragments and in these cases surgical treatment is frequently indicated. The ongoing development of arthroscopic techniques has led to quite a number of reports about arthroscopically assisted or total arthroscopic techniques in the treatment of these injuries. The advantages and disadvantages of arthroscopic concepts for the treatment of bony avulsions of the rotator cuff are presented with reference to the current literature.

Periprosthetic humeral fractures after shoulder and elbow arthroplasty.

Due to rapidly increasing numbers of arthroplasty surgeries of the upper extremity, periprosthetic humeral fractures after shoulder and elbow arthroplasty, formerly described as rare, may hence increase in the near future. Therefore the aim of the present work was to give an overview of the existing literature including possible classifications as well as an update on treatment concepts and experiences with own cases. After a literature research have been done, existing prevalence, classifications and treatment options, mostly described in case series, were processed to create an overview of the existing state of knowledge. Additionally 7 own cases are described in detail to show the different treatment options used at the authors department. The currently used classification systems take fracture location, angulation and rotation and fixation of the implant into account. Possible solutions for periposthetic fractures of the humerus include conservative management, open reduction and internal fixation for stable prosthesis and long stemmed implants for lose implants as well as the use of additional allo- or autogeneous bone grafting and reverse shoulder arthroplasty in revision cases with rotator cuff dysfunction. After all treatment of periprosthetic humeral fractures after shoulder and elbow arthroplasty remain a challenging problem.

[Arthroscopic stabilization of acute acromioclavicular joint dislocation]. / Arthroskopische Stabilisierung der akuten Schultereckgelenksprengung.

During the past few years arthroscopic and minimal invasive techniques for stabilization of acromioclavicular (AC) joint dislocations have gained increasing interest. Well established procedures for open surgery were modified and implemented to attain an arthroscopic level. Furthermore implants were developed which enable these reconstructive techniques to be performed arthroscopically without the disadvantages of open procedures. The short to mid-term results described so far concerning the clinical and radiological outcome of arthroscopic stabilization techniques show an at least equal outcome to those presented in open surgery.