Massive bone loss poses a significant challenge in defect reconstruction. The use of compacted allografts is a valuable technique to reconstruct bone stock. This study aimed to assess the impact of compression on the microstructure of native cancellous bone chips with a micro-CT analysis.Bone samples were harvested from 15 femoral heads donated by patients who underwent total hip arthroplasty. Bone chips were prepared using a bone mill. All samples with the same weight were compressed by 25% and 50% of their original volume and subsequently scanned with a micro-CT scanner to determine the microarchitectural morphology of the bone chips. Uniaxial compression test was carried out before and after a standardized compaction procedure.Comparing the samples without compaction to 50%, the number of trabeculae doubled, the volume ratio doubled, and the trabeculae spacing was reduced, showing voids of 800 μm on average. The number of interlocking possibilities tripled, while no differences were seen in the trabeculae morphology. Uniaxial compression test showed a yield limit after compaction of 0.125 MPa.Interlocking might occur three times more with a denser material than in a non-compacted sample. The increase in density comparable to manual intraoperative compaction did not lead to significant fragmentation of the allograft material. The assessed microarchitecture should, therefore, reassemble the intraoperative situation during a manual bone impaction procedure.

INTRODUCTION:Raman microscopic spectroscopyis a new approach for further characterization and detection of molecular features in many pathological processes. This technique has been successfully applied to scrutinize the spatial distribution of small molecules and proteins within biological systems by in situ analysis. This study uses Raman microscopic spectroscopyto identify any in-depth benefits and drawbacks in diagnosing Staphylococcus epidermidis in human bone grafts. MATERIAL AND METHODS:40 non-infected human bone samples and 10 human bone samples infected with Staphylococcus epidermidis were analyzed using Raman microscopic spectroscopy. Reflectance data were collected between 200 cm-1 and 3600 cm-1 with a spectral resolution of 4 cm-1 using a Senterra II microscope (Bruker, Ettlingen, Germany). The acquired spectral information was used for spectral and unsupervised classification, such as principal component analysis. RESULTS:Raman measurements produced distinct diagnostic spectra that were used to distinguish between non-infected human bone samples and Staphylococcus epidermidis infected human bone samples by spectral and principal component analyses. A substantial loss in bone quality and protein conformation was detected by human bone samples co-cultured with Staphylococcus epidermidis. The mineral-to-matrix ratio using the phosphate/Amide I ratio (p = 0.030) and carbonate/phosphate ratio (p = 0.001) indicates that the loss of relative mineral content in bones upon bacterial infection is higher than in non-infected human bones. Also, an increase of alterations in the collagen network (p = 0.048) and a decrease in the structural organization and relative collagen in infected human bone could be detected. Subsequent principal component analyses identified Staphylococcus epidermidis in different spectral regions, respectively, originating mainly from CH2 deformation (wagging) of protein (at 1450 cm-1) and bending and stretching modes of C-H groups (∼2800-3000 cm-1). CONCLUSION:Raman microscopic spectroscopyis presented as a promising diagnostic tool to detect Staphylococcus epidermidis in human bone grafts. Further studies in human tissues are warranted.

Introduction The purpose of this study was (1) to compare early wear rates in bedding-in periods of two highly cross-linked polyethylene liners frequently used in THA and (2) to evaluate risk factors indicating a possible higher wear rate. Materials and methods 1120 patients who received a Crossfire or a Marathon highly cross-linked (HXLPE) ultra-high-molecular-weight polyethylene liner in primary THA at our Department between 2004 and 2018 were retrospectively reviewed. Patients with (1) only alumina heads on HXLPE acetabular bearings, (2) a minimum of four radiographs per patient for EBRA analysis, (3) no osteolysis around the acetabular cup and (4) no dislocations that occurred during the study period were included. Results A total of 328 patients (female: 183; male: 145; Marathon: 179; Crossfire: 149) fulfilled the inclusion criteria. Mean follow-up was 24 (range 7–51) months. With 0.22 (SD 0.27) mm mean total wear for the Marathon was three times greater than for the Crossfire, namely 0.07 (SD 0.14) mm. Mean cup migration during the investigated follow-up period was 0.7 (SD 0.8) mm for the Pinnacle and 0.5 mm (SD 0.7) for the Trident PSL cups. Conclusion Initial early wear of highly cross-linked polyethylene in combination with alumina heads differs strongly between products. Long-term survivorship of these liners should be observed to determine whether early wear has an impact on aseptic loosening. Level of evidence Level III (retrospective comparative study with prospective cohort).

In this study, the potential of focus-variation microscopic imaging was evaluated in a study of morphological patterns of the potential medicinal fungus Hericium coralloides (Basidiomycota). We created three-dimensional reconstructions and visualizations using the imaging technique on a fresh H. coralloides basidioma. The aim was to approximate the spore dispersal efficiency of this basidiomata type regarding the investment of tissue biomass and its reproductive output (production of basidiospores). Results were correlated with published data gained from magnetic resonance imaging and micro-computed tomography. It is demonstrated that focus-variation microscopic imaging results in a more distinct picture of the morphology of the edible and potentially medicinal H. coralloides basidiomata. However, a direct measurement of spore production was not possible. Spore production could only be estimated in combination with a mathematical model because the surface was not directly measurable due to the cellular heterogeneity. However, focus-variation microscopic imaging allows a better and faster estimation of spore production compared with the published methods. Furthermore, it was found that a scanning resolution of 5× is sufficient for determining the fungal surface precisely because at a higher resolution artifacts occur, resulting in adulteration of the image.

To investigate the accuracy of preoperative digital templating for total hip arthroplasty (THA) at a certified arthroplasty center (EndoCert EPZmax). In a retrospective study design, we analysed 620 uncemented primary THAs for templating accuracy by comparing the preoperatively planned THA component size and the implanted size as documented by the surgeon. Templating was determined to be a) exact if the planned and the implanted component were the same size and b) accurate if they were exact ± one size. Moreover, we investigated factors that potentially influence templating accuracy: overweight and obesity (WHO criteria), sex, implant design, surgeon experience, preoperative diagnosis. Digital templating was done with MediCAD software. The Mann–Whitney U test and the Kruskal–Wallis test were used for statistical analysis. Templating was exact in 52% of stems and 51% of cups and was accurate in 90% of the stems and 85% of the cups. Regarding the factors potentially influencing templating accuracy, the type of cup implant had a significant influence (p = 0.016). Moreover, greater accuracy of stem templating was achieved in female patients (p = 0.004). No such effect was determined for the other factors investigated. We conclude that preoperative 2D templating is accurate in 90% of the stems and 85% of the cups. Greater accuracy may be achieved in female patients. In addition to gender, the type of implant used may influence planning accuracy as well. Surgeon experience, BMI and preoperative diagnosis did not influence templating accuracy. Level III (retrospective comparative study with prospective cohort).

Purpose: Recurrence of intrahepatic cholangiocarcinoma (ICC)after hepatic resection (HR) is a frequent problem and treatment is challenging. To evaluate the efficacy, safety and overall clinical outcome of HR of ICC with preferably aggressive liver-directed treatment of recurrence. Method: Between 2007 and 2019 72 consecutive patients underwent HR for primary ICC. If amenable, recurrent tumors were aggressively treated by repeated liver-directed therapy with curative intent (RLDT), either HR or stereotactic radiofrequency ablation (SRFA). Endpoints consisted of i) morbidity and mortality, ii) local and distant recurrence, iii) survival after recurrence (SAR), iv) and overall survival (OS). Potential clinicopathological factors influencing recurrence, recurrence management and long-term survival were analyzed. Results: After a median follow-up of 28 months, intrahepatic recurrence of ICC was observed in 43 patients (60.3%) with bildbar involvement being identified as an independent risk factor (p=0.044). 5 patients were subsequently treated by HR and 11 patients by SRFA, respectively. The remaining 27 patients underwent palliative treatment (chemotherapy or best supportive care) for first recurrence. Median SAR was superior among patients who underwent RLDT (38 months) as compared to palliative treatment (17 months, p=0.010). OS of patients who underwent aggressive RLDT was comparable to patients without recurrence (p=0.938) and was significantly better compared to patients receiving palliative treatment (p=0.018). The 5-year OS rates for patients without recurrence, the RLDT group and the palliative treatment group were 54.3%, 47.7% and 12.3%, respectively. By combining different liver-directed treatment options, the rate of curative re-treatment increased from 11.9% to 37.2%. Conclusion: Repeated HR is often precluded due to patient morbidity or anatomical and functional limitations. SRFA with local curative intent is safe, feasible and effective for recurrent ICC following HR with low morbidity levels and favorable clinical outcome.

Zusammenfassung Das Operationsziel des hier dargestellten Verfahrens ist eine Distalisierung der Tuberositas tibiae. Dieser Eingriff ist bei Patienten mit einer symptomatischen Patella alta indiziert, zum Beispiel bei Kniescheibeninstabilität. Die Osteotomie erfolgt v‑förmig. Der bei der Distalisierung gewonnene Knochenblock wird als proximales Widerlager eingebracht. Dadurch wird die mediolaterale und proximale Stabilität verbessert. Außerdem wird die Oberfläche vergrößert, was eine bessere Knochenheilung ermöglicht. Bei dem vom Operateur behandelten Patientenkollektiv von 10 Patienten ist es bei dieser Technik zu keiner sekundären Dislokation gekommen.

Purpose Polyethylene (PE) wear remains a common reason for revision surgery following total hip arthroplasty (THA). An established treatment method is isolated liner exchange in a well-fixed acetabular cup and entails a known high risk of hip dislocation after revision surgery. The purpose of this retrospective study was to determine the rate of hip dislocation after liner exchange. Methods Patients were included if (1) the PE liner was removable, (2) the acetabular shell was stable with acceptable orientation, (3) no osteolysis around the acetabular cup was found and (4) no dislocation of the THA occurred before revision surgery. We reviewed medical histories and performed radiological measurements using Einzel-Bild-Röntgen-Analyse (EBRA) software. EBRA measurements and statistical investigations were performed by two independent investigators. Results A total of 82 patients were included in our study. Mean follow-up was six (range: 3.6–9.9) years. In 13 (15.8%) patients THA dislocations occurred at a mean postoperative period of 20.2 (range: 1–44) weeks after revising the PE liner. This is equivalent to an absolute risk increase of 16% after revision surgery, which results in a number needed to harm of 6. This means that every sixth patient with isolated liner exchange can expect to experience dislocation due to wear. Conclusion In conclusion, isolated exchange of the polyethylene liner because of wear showed a high risk of dislocation and further cup revision. Our results suggest that the threshold for revising well-fixed components in the case of liner wear should be lowered. Trial Registration number and date of registration Number: 20140710-1012 and Date: 2016-03-09.

A 71-year-old woman with a known accessory cervical rib and distinct scoliosis was scheduled for elective, percutaneous stereotactic radiofrequency ablation of a non-resectable intrahepatic cholangiocellular carcinoma. Patient positioning and fixation using a Bluebag fixation system (Medical Intelligence, Schwabmünchen, Germany) and a dedicated adjustable armrest were customised in the patient while awake. In order to provide safe conditions for mask ventilation and tracheal intubation, the patient was returned to standard supine positioning without changing the position of the armrest. Following the induction of general anaesthesia, the patient's arm was returned to the previously defined position. Upon completion of the procedure and emergence from anaesthesia, the patient immediately reported symptoms of severe brachial plexus damage. Therefore, we suggest that awake positioning according to current recommendations does not completely preclude the possibility of neurologic injury.

Minimal invasive thermal ablation techniques have a key role in the treatment regimen of primary liver tumors. These relatively low-risk procedures are established in nonresectable liver tumors and even challenge the surgical approach, which is regarded as first-line treatment in eligible patients.The location and size of the liver tumor, the applied ablation, and guidance technique are crucial for treatment outcome. The confirmation of an adequate ablation zone including sufficient tumor overlap and a safety margin (A0 ablation analogous to R0 resection) is crucial to minimize local recurrence rates and improve survival. A variety of different ablation devices is available. The outcome of conventional computed tomography- or ultrasound-guided thermal ablation in small lesions is well comparable to surgery. However, in liver lesions with large diameter overlapping ablation zones are required to ensure an adequate ablation margin. Therefore, stereotactic techniques in combination with a multiple needle approach, three-dimensional trajectory planning, and image fusion for intraoperative treatment evaluation have been successfully introduced.

Percutaneous ablation techniques offer a vast armamentarium for local, minimally invasive treatment of liver tumors, nowadays representing an established therapeutic option, which is integrated in treatment algorithms, especially for non-resectable liver tumors. The results of ablative treatment compare very well to surgical treatment in liver lesions, and confirm that these techniques are a valuable option for bridging for transplantation. Different techniques have been established to perform tumor ablation, and the feasibility varies according to the procedure and technical skills of the operator, depending on the size and location of the liver lesion. In recent years, stereotactic multi-needle techniques using 3D trajectory planning, general anesthesia, and tube disconnection during needle placement have had a strong impact on the application range of ablation for liver tumors.

Purpose: We compared the targeting accuracy and reliability of two different electromagnetic navigation systems for manually guided punctures in a phantom.Materials and Methods: CT data sets of a gelatin filled plexiglass phantom were acquired with 1, 3, and 5 mm slice thickness. After paired-point registration of the phantom, a total of 480 navigated stereotactic needle insertions were performed manually using electromagnetic guidance with two different navigation systems (Medtronic Stealth Station: AxiEM; Philips: PercuNav). A control CT was obtained to measure the target positioning error between the planned and actual needle trajectory.Results: Using the Philips PercuNav, the accomplished Euclidean distances were 4.42 +/- 1.33mm, 4.26 +/- 1.32 mm, and 4.46 +/- 1.56 mm at a slice thickness of 1, 3, and 5 mm, respectively. The mean lateral positional errors were 3.84 +/- 1.59 mm, 3.84 +/- 1.43 mm, and 3.81 +/- 1.71 mm, respectively. Using the Medtronic Stealth Station AxiEM, the Euclidean distances were 3.86 +/- 2.28 mm, 3.74 +/- 2.1 mm, and 4.81 +/- 2.07 mm at a slice thickness of 1, 3, and 5 mm, respectively. The mean lateral positional errors were 3.29 +/- 1.52 mm, 3.16 +/- 1.52 mm, and 3.93 +/- 1.68 mm, respectively.Conclusion: Both electromagnetic navigation devices showed excellent results regarding puncture accuracy in a phantom model. The Medtronic Stealth Station AxiEM provided more accurate results in comparison to the Philips PercuNav for CT with 3 mm slice thickness. One potential benefit of electromagnetic navigation devices is the absence of visual contact between the instrument and the sensor system. Due to possible interference with metal objects, incorrect position sensing may occur. In contrast to the phantom study, patient movement including respiration has to be compensated for in the clinical setting.Key points:Commercially available electromagnetic navigation systems have the potential to improve the therapeutic range for CT guided percutaneous procedures by comparing the needle placement accuracy on the basis of planning CT data sets with different slice thickness.Citation Format:.Putzer D, Arco D, Schamberger B et al. Comparison of Two Electromagnetic Navigation Systems For CT-Guided Punctures: A Phantom Study. Fortschr Rontgenstr 2016; 188: 470-478

Eine akute Bandruptur des lateralen Bandkomplexes am oberen Sprunggelenk wird konservativ therapiert. Versagt diese und es kommt zu einer chronischen lateralen Instabilität am oberen Sprunggelenk, kann eine stabilisierende Operation ein gutes Ergebnis erzielen. Lässt die Bandqualität es zu, ist eine anatomische Rekonstruktion die beste Operationsmethode.

Um die Zufriedenheit der Patienten mit den Leistungen der Univ.-Klinik für Radiologie Innsbruck zu überprüfen, wurden 93 Meldungen der Anlaufstellen für Patientenanliegen zwischen Jänner 2009 und September 2014 ausgewertet.

BACKGROUND:Baker's cysts are related to increased intra-articular pressure. The causes may be inflammatory, degenerative or traumatic disorders. Owing to the increased intra-articular pressure a cyst protrudes between the semimembranosus and the medial gastrocnemius tendons. The traditional treatment for a Baker's cyst is open resection. As an alternative, an arthroscopic procedure can be performed, which is demonstrated by the video on surgical technique that accompanies this short report.SURGICAL TECHNIQUE:From the anterolateral portal the arthroscope is advanced through the intercondylar notch (below the posterior cruciate ligament) to the posteromedial recess. Under visual control, a posteromedial portal is created followed by identification of the capsular fold separating the cyst from the joint cavity. This fold (valvular mechanism) is resected with a shaver from the posteromedial portal until a large enough connection exists between the joint and the cyst (cyst decompression). After the decompression, the arthroscope is inserted from the posteromedial portal directly into the cyst cavity. Subsequently, the inner wall of the cyst is removed with the shaver via an additional far posterior cystic portal. It is obligatory to treat the associated intra-articular pathological condition. In our video a medial meniscal lesion is treated with partial meniscectomy.

Problemstellung: Ziel dieser Studie ist es, die diagnostische Genauigkeit der 18F-FDG-PET/CT in der Abklärung eines Rezidivverdachts bei Patientinnen mit Ovarial-Karzinom nach Operation und/oder Chemotherapie zu eruieren.

To find and evaluate characteristic magnetic resonance imaging (MRI) patterns for the differentiation between Ewing sarcoma and osteomyelitis.