Interprothetische Frakturen am Femur

The treatment of interprosthetic fractures is challenging and the incidence is increasing as a result of increasing patient longevity and rising arthroplasty rates. Interprosthetic fractures occur between arthroplasty stems or any intramedullary implant that has been implanted for fracture fixation. Management of these fractures is a complex undertaking. The majority of fractures are localized at the femoral supracondylar level after knee resurfacing arthroplasty. The fixation status of the arthroplasty component determines the management strategies. As a result of clinical and biomechanical studies, loosening of the implant usually requires revision arthroplasty, whereas minimally invasive reduction and locked internal fixation is the treatment of choice for stable implants. Minimally invasive surgery is necessary to not further compromise local perfusion. As locked plating provides superior biomechanical stability, the use of cerclage cables should be carefully evaluated. Complex fracture configurations, inferior bone stock or an intramedullary canal that is already occupied by support structures might obviate the implantation of long revision stems and might require a more extensive approach (e.g., total femoral arthroplasty).     

Zur Bedeutung der MRT-Diagnose „bone bruise“ bei kindlichen Wirbelsäulenverletzungen

ZusammenfassungHintergrund Die MRT stellt ein sensitives, nicht strahlenbelastendes bildgebendes Verfahren dar und bietet sich daher für die Diagnostik kindlicher Wirbelsäulenverletzungen an. Als ein indirektes Verletzungszeichen lässt sich hierbei u. U. ein sog. bone bruise nachweisen, ohne dass weitere Verletzungen sichtbar werden. Ziel der vorliegenden Arbeit war es, die klinische Bedeutung dieser Diagnose bei kindlichen Wirbelsäulenverletzungen zu untersuchen.Patienten und Methoden Zwischen 1998 und 2003 wurden in unserer Klinik insgesamt 66 Kinder mit Wirbelsäulenverletzungen konservativ behandelt. 34 dieser Kinder erhielten während der Primärdiagnostik eine MRT. Im Rahmen einer retrospektiven Studie wurden 20 Kinder, bei welchen die Diagnose einer Wirbelkörperverletzung vorwiegend durch den Nachweis eines bone bruise im initialen MRT geführt worden war, sowohl klinisch als auch mittels MRT nachuntersucht.Ergebnisse Alle 20 Kinder gaben bei der Nachuntersuchung subjektiv weitgehende Beschwerdefreiheit an. Bei der objektiven Untersuchung fanden sich keine klinischen Auffälligkeiten. Bei keinem der Kinder war im Rahmen der Nachuntersuchung MR-tomographisch eine Persistenz des bone bruise feststellbar. Eine sekundäre Sinterung der betroffenen Wirbelkörper war in keinem Fall aufgetreten.Schlussfolgerung Kindliche Wirbelsäulenverletzungen, die mit einem mittels MRT nachgewiesenen bone bruise ohne weitere bildmorphologische knöcherne oder diskoligamentäre Läsionen einhergehen, sind in der Regel als prognostisch günstig einzustufen. Bei entsprechender Therapie, die in einer kurzfristigen, schmerzadaptierten Bettruhe und einer anschließenden frühfunktionellen Behandlung besteht, wurden bei unseren Patienten keine sekundären Sinterungen beobachtet.* Beide Autoren haben gleichen Anteil an dieser Arbeit und teilen sich die Erstautorenschaft.     

Effectivity of laser-induced thermotherapy: in vivo comparison of arterial microembolization and complete hepatic inflow occlusion

BACKGROUND AND OBJECTIVES: Laser-induced thermotherapy (LITT) is a promising method for local treatment of liver metastases. The aim of this study was to compare the effect of LITT on lesion size when combined with hepatic arterial microembolization or complete hepatic blood flow occlusion. STUDY DESIGN/MATERIALS AND METHODS: In a porcine liver model, LITT (30 W 15 minutes) was performed with either normal (n = 12), partially interrupted (arterial microembolization via a hepatic artery catheter n = 12) or completely interrupted hepatic perfusion (Pringle's maneuver, n = 12). LITT lesions were macro- and microscopically assessed after liver dissection. RESULTS: Hepatic inflow occlusion led to a fourfold increase in lesion volume after arterial microembolization and a ninefold increase after complete interruption (6.3. cm3 vs. 27.1 cm3 vs. 58.8 cm3, P < 0.01). CONCLUSIONS: Interrupting hepatic perfusion significantly increases lesion volumes in LITT. This beneficial effect can also be achieved in the percutaneous application mode by LITT combined with arterial microembolization via a hepatic artery catheter.     

Current TNM classification of renal cell carcinoma evaluated: revising stage T3a

PURPOSE:: Recent studies of rare cases of pT3a renal cell carcinoma extending directly into the adrenal gland showed worse survival than in other pT3a cases and recategorization as stage pT4 was suggested. We assessed the prognostic validity of a stage pT3a diagnosis based on perirenal fat infiltration. MATERIALS AND METHODS:: The records of 1,794 patients with renal cell carcinoma who underwent surgical resection between 1975 and 2000 at our institution were analyzed retrospectively. Focusing on pT3a tumors, as defined by perirenal fat infiltration, numerous clinical and histopathological parameters were investigated by univariate and multivariate statistical methods with cancer specific survival as the primary end point. RESULTS:: We identified 237 of 1,794 patients with perirenal fat infiltration, classified as having pT3a disease. In patients with pT3a tumors tumor size was a significant parameter predicting survival. The most significant cutoff value for tumor size in pT3a disease was 7 cm. Patients with distant metastasis had a worse prognosis independent of T classification. Therefore, to assess the prognostic value of the current T classification in regard to T3a tumors we excluded patients with tumor stage cM+ for further subgroup analysis. Survival comparison of pT1 pNall, cM0 (744 of 1,794 cases) and pT3a pNall, cM0 7 cm or less (100 of 237) as well as pT2 pNall, cM0 (265 of 1,794) and pT3a pNall, cM0 greater than 7 cm (93 of 237) yielded similar results. After splitting pT3a into a modified T1/T2 classification a significant difference in 5-year survival analysis for a modified T1/T2 stage was found (pT1 plus pT3a less than 7 cm 90% vs pT2 plus pT3a greater than 7 cm 73%, p <0.001). Subsequently multivariate analysis in all 1,794 patients showed that modified T stage was an independent significant predictor of cancer specific survival. CONCLUSIONS:: We suggest revising the current pT3a classification based on perirenal fat infiltration but rendering a modified pT1/pT2 classification, which resolves pT3a cases without the loss of prognostic validity. Perirenal fat infiltration should not be used to assign T category. Tumors directly infiltrating the adrenal gland should be reclassified as T4.     

Comparison of conventional radiography and MDCT in suspected scaphoid fractures

AIM: To determine the diagnostic accuracy and radiation dose of conventional radiography and multidetector computed tomography(MDCT) in suspected scaphoid fractures.METHODS: One hundred twenty-four consecutive patients were enrolled in our study who had suffered from a wrist trauma and showed typical clinical symptoms suspicious of an acute scaphoid fracture. All patients had initially undergone conventional radiography. Subsequent MDCT was performed within 10 d because of persisting clinical symptoms. Using the MDCT data as the reference standard, a fourfold table was used to classify the test results. The effective dose and impaired energy were assessed in order to compare the radiation burden of the two techniques. The Wilcoxon test was performed to compare the two diagnostic modalities.RESULTS: Conventional radiography showed 34 acute fractures of the scaphoid in 124 patients(42.2%). Subsequent MDCT revealed a total of 42 scaphoid fractures. The sensitivity of conventional radiography for scaphoid fracture detection was 42.8% and its specificity was 80% resulting in an overall accuracy of 59.6%. Conventional radiography was significantly inferior to MDCT(P < 0.01) concerning scaphoidfracture detection. The mean effective dose of MDCT was 0.1 m Sv compared to 0.002 m Sv of conventional radiography.CONCLUSION: Conventional radiography is insufficient for accurate scaphoid fracture detection. Regarding the almost negligible effective dose, MDCT should serve as the first imaging modality in wrist trauma.     

Cystic lesions of the pineal region – MRI and pathology

Pineal lesions are rare. Tumours in this location comprise 0.4–1 % of intracranial tumours. They grow mainly as solid-mass lesions, and cystic tumours are not common. On MRI, a cystic configuration is associated usually with non-neoplastic pineal lesions rather than with a tumour, but analysis does not allow cystic pineal tumours to be distinguished from glial cysts with certainty. We compared neuroradiological and pathological data from 13 cystic pineal lesions, analysing preoperative MRI. Formalin-fixed, paraffin-embedded surgical specimens were stained routinely and immunocytochemically, using the streptavidin-biotin-complex method. Histology revealed six pineocytomas, four glial cysts, an arachnoid cyst, a low-grade astrocytoma and a teratoma. Signal characteristics of pineocytomas were similar in many respects to those of glial pineal cysts. Histomorphological analysis allowed unambiguous discrimination between pineocytomas and glial pineal cysts. Received: 19 July 1999/Accepted: 3 September 1999     

Solid Aneurysmal Bone Cyst of the Metacarpal Bone

Background: A solid aneurysmal bone cyst is a rare tumor-like lesion of bone. As conventional aneurysmal bone cyst it is a benign, although locally destructive lesion. While the aneurysmal bone cyst is characterized by cyst-like walls of predominantly fibrous tissue filled with free-floating blood, the solid variant shows essential findings identical to those seen in the walls of conventional aneurysmal bone cysts, except that the lesion almost completely lacks the blood-filled spaces and the cyst walls. Differential Diagnosis: Aneurysmal bone cysts and solid aneurysmal bone cysts may easily be mistaken for a malignant tumor, both radiologically and histologically, due to their great rate of growth, tremendous destruction of bone, and marked cellular exuberance in the early to mid phase of development. Case Study: A case of solid aneurysmal bone cyst of the fourth metacarpal is presented. In spite of the relatively unusual location it allows to clearly demonstrate both, the task of correct differential diagnosis and the surgical spectrum of therapy including local recurrence.     

Thrombelastographic coagulation analysis following in vitro and in vivo haemodilution with hydroxyethyl starch (HES)

In the study presented the effects of in vitro hemodilution with HES on coagulation are compared with the effects of in vivo hemodilution using thrombelastography (TEG). The in vivo hemodilution was performed by the i. v. infusion of 1000 ml 6 % solution of hydroxyethyl starch HES (2 formulations with HES 130/0.4 and one formulation with HES 200/0.5) in healthy volunteers during 30 min. The in vitro hemodilution was performed with blood samples taken from the volunteers before the infusion was started. These samples were diluted with HES-solution until the same hemoglobin concentration measured at the end of the infusion was attained. The in vivo TEG-parameters remained in the reference range of the method, however all in vitro TEG-parameters are out of the range of normal values. The isolated interpretation of the in vitro data shows an impairment of blood coagulation. The shortening of the reaction time as an indicator for the initiation of blood clotting points to activated coagulation by in vivo hemodilution with HES, whereas in vitro the prolongation of the reaction time is indicative for retardation of clotting. The evaluation of the TEG-parameters and of other clotting parameters determined prior to the beginning of the infusion, at the end of the infusion and four hours after termination of the infusion of HES 130/0.4 and of HES 200/0.5 to healthy volunteers show alterations of blood coagulation parameters caused mainly by dilutional effects. The more pronounced alterations found in vitro cannot be interpreted as impairment of haemostasis in vivo. On the other hand, the likewise haemodilution in vitro causes an impairment of coagulation. Therefore, the effects of in vitro hemodilution with HES on coagulation differ qualitatively and quantitatively from the effects of in vivo hemodilution.     

Was gibt’s Neues beim Harnblasenkarzinom?

A review of the current literature provides new scientific insights into the diagnosis, prognosis and novel molecular targets for bladder cancer. The new WHO classification refines our staging system and influences treatment options. International clinical databases provide new tools for calculating the individual risk for bladder cancer recurrence and progression. Systematic gene cluster analysis defines multimarker panels that can serve as robust predictors of outcome. Discoveries of new signaling pathways in bladder cancer are leading to novel molecular targets for innovative therapies.     

Age dependent secretion of LH and ACTH in healthy men and patients with erectile dysfunction

OBJECTIVES: Age dependent secretion of testicular and adrenal androgens was examined in healthy men and patients with erectile dysfunction (ED). METHODS: In 95 healthy men (age 20-74 years) and 739 patients with ED, luteineizing hormone (LH, n = 739), adrenocorticotropic hormone (ACTH, n = 480) and the secretion products of testis and adrenal gland testosterone (T, n = 750), free testosterone (fT, n = 718), dehydroepiandrosteronesulfate (DHEAS, n = 598) and cortisol (n = 538) were measured. RESULTS: In healthy men, LH was measured from 0.75-8.58 mIU/ml and ACTH from 10.59-121.7 pg/ml. Statistically, age was not correlated to LH (P = 0.573) and ACTH (P = 0.833) in healthy men. The secretion products T (P < 0.05), fT (P < 0.001), DHEAS (P < 0.001) and cortisol (P < 0.05) declined significantly with age in healthy persons. In patients with ED, a significant age dependent increase of LH (P < 0.05, n = 739), but not ACTH (P = 0.469, n = 480) was found. T (P < 0.001, n = 736), fT (P < 0.001, n = 718) and DHEAS (P < 0.001, n = 598), but not cortisol (P = 0.307, n = 538) declined in age dependent patients with ED. Age matching revealed a statistical significant elevation (P < 0.05) only for LH (n = 659) in comparison to healthy men (n = 94), all other hormones were not different in both groups. CONCLUSION: An LH-increase in patients with erectile dysfunction underlines the importance of Leydig cell degeneration in this disease, but age dependent decline of T secretion was comparable to healthy men, demonstrating a working hypophyseal-testicular-axis. Indication of androgen replacement is therefore limited to selected cases.