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Zusammenfassung In einer experimentellen Studie wurde nach Applikation von Schweine-Pancreas-Kallikrein die Lokalisation und Aktivitat von Kallikrein im Hoden-Nebenhodenbereich immunologisch und enzymatisch untersucht. Es konnte eine Anreicherung des applizierten Kallikreins im Tubulusepithel des Ductus epididymidis des Nebenhodens, nicht aber im Keimepithel des Hodens nachgewiesen werden. Experimental Investigations Concerning the Specific Concentration of Kininogenases in Testis and Epididymis

The activity of plasminogen activators and plasmin inhibitors in articular capsules of the hip and knee joints in rheumatoid arthritis, chronic traumatic inflammation, arthrosis and aseptic loosening of prosthesis was determined histochemically and correlated with the degree of mobility in osteoarthrosis of the hip. Microscopically unchanged articular capsules were employed as reference sites. In inflammatory articular diseases the plasminogen activator activity was significantly reduced, whereas it remained unchanged in arthrosis and necrosis of the heas of the femur, and significantly enhanced in aseptic loosening of prosthesis. Plasmin inhibitor activity was established in joint capsules with inflammatory changes only; in case of rheumatic inflammation, it was higher than with traumatic inflammation. In osteoarthrosis of the hip there is a positive correlation between joint mobility and plasminogen activator activity. The results point towards involvement of the local fibrinolytic system in joint diseases; however, no definite statement can be made with regard to possible causative linkups.

Whole body hyperthermia was produced in 14 patients with conventionally incurable malignant disease. The technique consisted of arteriovenous shunting involving extracorporeal circulation with heat exchange during general anaesthesia. A temperature of 41.8 degrees C was maintained for periods of 6 hours. After achieving hyperthermic temperatures treatment was enlarged by administration of 5-fluorouracil (1000 mg) in patients with colorectal carcinoma and by dacarazine (200 mg/m2) in patients with malignant melanoma. In 5 out 6 patients with stage IV colorectal carcinoma stabilisation of the disease was seen for an average of 10 months. In contrast, progression of the disease was seen in patients with malignant melanoma and mean survival was only 5 months. These preliminary results in a small number of patients indicate that 1. induction and maintenance of whole body hyperthermia is clinically possible, 2. technical requirements are considerable, however feasible, 3. different tumours react differently to treatment.

198 Phonoarthrographic examinations of the knee joint are reported on. An analysis was then carried out on the noise in knee joints with clinically and operatively demonstrated gonarthritis, chondromalacia of the patella, meniscus lesion and complex ligament injuries of the knee joint. Our results show that statistically, due to the division of the noise peaks into frequency groups, the four examined conditions could be separately identified. A practical use is possible now, in diagnosis as well as in examining the progress in knee joint disease. The representation of pathological-anatomical changes by phonoarthrograhy allows the effectiveness of therapeutical measures to be checked. This simple painless examination method provides an additional aid to diagnosis.

Discussing the causes of aseptic loosening mechanism of total hip replacement shear forces resulting from friction between cup and head are often mentioned. Therefore measurements of friction torque in explanted endoprostheses were performed in a new hip simulator to evaluate the influence of friction on the loosening. Differing from other simulators the physiological deformation of the hip bones was imitated by a bending beam. The measured values were compared with mathematically and experimentally found limit loads of the cup fixation. It was shown that the only influence of the shear forces transferred by friction was no significantly dangerous factor for the interface between bone and bone cement of a primarily fixed cup.

The use of composite materials in orthopaedic surgery permits the design of implants with varying degrees of stiffness. A system of carbon fibre reinforced epoxy hip stems was investigated and compared to the mechanical safety of metal ones. Special attention has been paid to the fact that torsional moments are the common failure mechanism of composite materials. In total 74 hip stems (three different sizes) have been tested under static and dynamic loading conditions according to ISO 7206. A group of 27 implants was pre-conditioned for 75 days in 80 degrees C Ringer's solution to discover potential degradation effects of absorbed fluids. The carbon fibre hip stems proved to reach run-out loads higher than conventional metal ones. Moisture absorption didn't influence the mechanical properties within the range of the experimental accuracy. The calculated fatigue stress of 750 MPa permits further optimization of stiffness parameters without the risk of implant fracture.

Triggerpunkte (TrP), kleine palpable Verhartungen im Muskel mit Schmerzausstrahlung, spielen in der manuellen Medizin eine wichtige Rolle, da sie meist mit weiteren Funktionsstorungen im Bewegungssystem in Zusammenhang stehen. Zu ihrer Objektivierung wurde ein Messgerat zur Bestimmung der Gewebespannung, ein Tissue-Tensiometer (TTM), entwickelt. In einer Pilotstudie wurde die Gewebespannung an den TrP, in deren Umgebung, an Vergleichsmuskeln und nach einer Behandlung gemessen. In 82% der Falle stimmten die palpierten mit den gemessenen TrP uberein. In 90% war die Gewebespannung am Ort des TrP nach dessen Behandlung verringert. In dem den TrP umgebenden Gewebe war nach der TrP-Behandlung keine Veranderung der Gewebespannung festzustellen. Die Ergebnisse zeigen, dass sich Triggerpunkte mit dem TTM verifizieren lassen. Ebenso konnten Therapieeffekte mit der lokalen postisometrischen Relaxation nach Lewit nachgewiesen werden. Das TTM erscheint geeignet, palpable Triggerpunkte fur Studienzwecke zu „objektivieren“.

To investigate whether determination of right ventricular end-diastolic volume (RVEDV) and right ventricular ejection fraction (RVEF) can be performed with reasonable accuracy and reproducibility using a conventional slow response thermistor pulmonary artery catheter (CPAC) applying an adaptive algorithm.To study RVEDV and RVEF simultaneously with pulmonary artery catheters equipped with slow and fast response thermistors (FRPAC) under a broad range of cardiac output.Laboratory of Institute of Experimental Surgery, Technical University.11 anaesthetised piglets.Hypovolemia (V-) was induced by withdrawal of blood up to 50 ml/kg, hypervolemia (V+) was produced by retransfusing blood and adding up to 30 mg/kg hydroxyethyl starch. In 5 animals in phases V- and V+ beta-adrenergic stimulation was achieved with dobutamine. Finally pulmonary artery hypertension was induced by infusion of small air bubbles.Cardiac output (CO), RVEDV and RVEF were determined simultaneously with FRPAC and CPAC placed in the same pulmonary artery branch. Measurements were repeated 8 times sequentially in steady state normovolemia. A total of 130 measurements could be analysed. The coefficient of variation was 6.7 +/- 4.2% for CO(FRPAC) and 4.6 +/- 1.7% for CO(CPAC); for RVEF it was 9.7 +/- 6.2% (FRPAC) and 9.9 +/- 3.9% (CPAC); for RVEDV it was 11.6 +/- 4.8% (FRPAC) and 8.54 +/- 3.2 (CPAC). Mean difference (bias) was 0.06 +/- 0.39 l/min for CO measured with both methods, 19 +/- 35 ml for RVEDV and -3.3 +/- 6.5% for RVEF. CO(CPAC) displayed a strong correlation to CO(FRPAC) (R = 0.97, p = 0.001) as well as RVEF (R for RVEF(CPAC) versus RVEF(FRPAC) = 0.90, p = 0.001). R for RVEDV(CPAC) versus RVEDV(FRPAC) was 0.67, p = 0.001. We conclude that this animal study demonstrates good agreement between RVEF and RVEDV obtained with catheters equipped with a fast response thermistor or with a conventional slow response thermistor allowing accurate monitoring of right ventricular function with a conventional pulmonary artery catheter.

Grundlagen: Die aszendierende Cholangitis stellt eine mogliche Komplikation nach biliodigestiven Anastomosen dar. In diesem Versuchsvorhaben sollten 3 verschiedene operative Techniken mit bakteriologischen Untersuchungen der Gallenwege und des oberen Gastrointestinaltraktes verglichen und die Frage pathologischer Fehlbesiedelung geklart werden.

Cells of the breast cancer cell line MCF7 were exposed to electromagnetic fields (EMF), A sinusoidal signal (12 h/day) was generated by a function generator with a frequency of 20 Hz and a maximum magnetic induction of 5.3 mT. After 6 days EMF subjected cells showed a significant increase in mitochondrial activity as shown by MTT-assay. At the same time EMF exposed cells investigated by scanning electron microscopy indicated intensified membrane ruffling and pronounced microvilli development compared with control cells.

Eine Ubersicht uber die bisherigen klinischen Erfahrungen mit nieder-molekularen Heparinen in der Allgemeinchirurgie fuhrt zu dem Ergebnis, das mit nur 1mal taglicher Gabe von niedermolekularem Heparin eine mindestens ebenburtige antithrombotische Effizienz wie unter herkommlicher Low-dose-Heparinprophylaxe erreicht werden kann, bei welcher durch die mehrfach applizierten Injektionen eine 2- oder 3mal tagliche Belastigung von Patienten und Pflegepersonal in Kauf genommen werden mus. Auch die Vertraglichkeit von niedermolekularen Heparinen gegenuber unfraktioniertem Heparin scheint gleich zu sein.

The use of composite materials in orthopaedic surgery permits the design of implants with varying degrees of stiffness. A system of carbon fibre reinforced epoxy hip stems was investigated and compared to the mechanical safety of metal ones. Special attention has been paid to the fact that torsional moments are the common failure mechanism of composite materials. In total 74 hip stems (three different sizes) have been tested under static and dynamic loading conditions according to ISO 7206. A group of 27 implants was pre-conditioned for 75 days in 80 degrees C Ringer's solution to discover potential degradation effects of absorbed fluids. The carbon fibre hip stems proved to reach run-out loads higher than conventional metal ones. Moisture absorption didn't influence the mechanical properties within the range of the experimental accuracy. The calculated fatigue stress of 750 MPa permits further optimization of stiffness parameters without the risk of implant fracture.

The biomechanical properties of cryopreserved, autoclaved, irradiated and chemically treated cortical bone harvested from rat tibiae were evaluated in three-point bending. Biomechanical parameters (maximum bending load, deflection, failure energy and stiffness) are not altered by cryopreservation (-70 degrees C, 28 days) or irradiation with doses of 1 kGy or 5 kGy. The maximum bending load of autoclaved (134 degrees C, 3 min) or irradiated (25 kGy) cortical bone is reduced to 82% and 74% compared that of controls tested immediately after death (100% = 74.4 +/- 6.6 N). Extension of the autoclaving time from 3 to 5 min or irradiation with 50 kGy diminishes the bending load (28% after autoclaving, 48% after irradiation), deflection and failure energy. Stiffness is altered by autoclaving only. If a sterilization process is combined with deep freezing, better biomechanical values are obtained by sterilizing the bone before deep freezing than vice versa. The bending loads for autoclaving and irradiation before deep freezing are 68.8 +/- 9.4 N and 50.8 +/- 7.9 N, as against 51.7 +/- 2.7 N and 43.1 +/- 3.9 N for autoclaving and irradiation of previously cryopreserved bone. Whereas treating bone with tetrahydrofurane does not alter its biomechanical behavior, 80% ethanol leads to a reduction of structural properties.

Die Anzahl der Revisionseingriffe bei Huftgelenksendoprothesen ist in den letzten Jahren stark angestiegen [9]. Bei RevisionseingrifFen werden haufig Defekte der Kortikalis des Femurs - u. a. durch Osteolyse, Perforation oder Fraktur - beobachtet. Bisher versucht man die Defektstrecke entweder durch Verwendung von Knochenzement oder durch Verwendung einer Langschaftprothese zu uberbrucken [4]. Da vor allem bei jungeren Patienten Revisionseingriffe sehr wahrscheinlich sind, ware statt der vorher genannten Moglichkeiten, der knocherne Wiederaufbau des Femurs wunschenswert [4,7]. Durch den Wiederaufbau sollte die Stabilitat der Revi-sionsprothese, die Festigkeit des Femurschafts und die optimale Kraftubertragung auf das proximale Femur zur Vermeidung von Osteolysen gewahrleistet sein [4].

Aufgrund der sehr varianten Symptomatik, vom klinischen Vollbild bis hin zur vollig asymptomatischen thrombotischen Verlegung auch groser Venen, sind prozentuale Angaben uber die Inzidenz von geringer Zuverlassigkeit und unser Wissensstand uber die Pathophysiologie nur unvollstandig. Es ist jedoch eindeutig abgesichert, das klinisch manifeste Thrombosen in bestimmten Risikosituationen vermehrt auftreten und insbesondere Folgeerkrankungen und Komplikationen bei operativen Eingriffen sein konnen. Dabei ist offensichtlich die Thrombosehaufigkeit von der Art des Eingriffs beeinflust (Tabelle 1).

Aus der Zeit, als verletzte Menisci noch groszugig entfernt wurden, resultiert eine grose Zahl von schlechten Langzeitergebnissen [1, 7]. Allerdings ist es bis heute nicht moglich, alle verletzten Menisci zu rekonstruieren bzw. zu erhalten. Eine Umfrage an 322 Kliniken im deutschsprachigen Raum [6] ergab, das vom uberwiegenden Teil der Operateure lediglich Langsrisse im Bereich der gut durchbluteten Ausenzone des Meniskus einer Meniskusnaht unterzogen werden, wahrend Risse der Innenzone, Korbhenkelrisse und komplexe Risformen uberwiegend durch Meniskusteilresektion behandelt werden. Zwar wird die Indikation zur Meniskusnaht gegenuber der Praxis in der Literatur [5] groszugiger gesehen, allerdings wird die Heilungsmoglichkeit von Meniskusrissen insbesondere durch die spezielle Durchblutungssituation begrenzt. Fur komplexe Lasionen, die zum Meniskusverlust fuhren, steht derzeit noch keine anerkannte Therapie zur Verfugung. Die allogene Meniskustransplantation, als das in der Weltliteratur am haufigsten verwendete Verfahren zum Meniskusersatz, ist mit dem Risiko einer Infektionsubertragung behaftet und alle Ansatze fur die Entwicklung fur Meniskusprothesen sind bisher fehlgeschlagen. Wunschenswert ware eine Meniskusrekonstruktion aus autogenem Gewebe, das in morphologischer und funktioneller Hinsicht den Meniskus ersetzen kann. Neben Hoffa-Fettkorper [4] oder Periost wurde auch Sehnengewebe [2] zum Meniskusersatz vorgeschlagen.

The cruciate ligaments are generally regarded as regulators of the joint kinematics, but also increasingly as a "Sensory organ" regulating the periarticular musculature, which influences the position of the contact surfaces and the direction and magnitude of the resultant forces. Indirectly, therefore, they influence the long-term stress distribution, which is itself reflected in the distribution of the subchondral mineralisation. An experimental investigation was therefore undertaken to see whether, in terms of this distribution, the distribution of the stress alters postoperatively, since this could be regarded as an early cause of degenerative change. We examined the distribution of the subchondral mineralisation of six tibiae from six adult Merino sheep 1 year after anterior cruciate ligament reconstruction with patellar tendon. The contralateral tibia we used as controls. Maximum subchondral mineralisation of both the medial and the lateral joint surfaces in all the control joints was found to be central. In the treated knees, however, the medial joint surface maxima were found to have been displaced towards the dorsomedial edge of the surface in every case. If the density pattern on the control side is accepted as the expression of a normal stress distribution, the distribution patterns on the treated side must indicate a pathologic distribution of stress. Reconstruction of the anterior cruciate ligament is therefore--at least in the animal model--not able to prevent the development of a pathologic stress distribution.(ABSTRACT TRUNCATED AT 250 WORDS)

The articulating surfaces of retrieved ceramic heads (n = 37, Al 2 O 3 ) implanted with cemented and non cemented UHMWPE-cups or cementless CFRP-cups (Carbon Fiber Reinforced Plastic) were compared using surface measurement techniques and Scanning Electron Microscopy (SEM). There were no surface changes regarding roughness, geometry (diameter and sphericity) and morphology of retrieved ceramic balls compared to virgin balls of the related product period. However this statement must be limited to the observed implantation times.

Divalent carbonic acid halides have been used to fix heparin onto biomaterials of biological origin, however, the effect of this process on the coagulation profile induced by heparin has not yet been clearly determined. To investigate this, commercially available unfractionated and low molecular weight heparins were treated with the corresponding halides of adipic and glutaric acid. Clotting tests and chromogenic substrate assays were used to characterize the influence of these derivatives on the clotting mechanism. In a thrombosis model in rats, the anticoagulant and antithrombotic effects of these substances were also analyzed. The in vitro data indicate a loss of the anticoagulant profile. Heparin-catalyzed acceleration of thrombin and factor Xa-inhibition by AT III were diminished following derivatization, although the heparin cofactor II activity was unaltered. However, in an animal model the antithrombotic properties of these heparin derivatives were reduced but still significant. These experiments were repeated with acetylchloride derivatization revealing comparable results.

The effects of preservation and sterilization on the structural properties of cortical bone were investigated. Specimens of cortical bone from rat tibiae were frozen (-70 degrees C for 28 days), freeze-dried, irradiated (1, 5, 25 and 50 kGy) or autoclaved (at 134 degrees C for 3 or 5 min), and examined by scanning electron microscopy. Cryopreservation and irradiation had no deleterious effects on the surface structure of the cortical bone. Freeze-drying caused microcracks running parallel to the mineralized fiber bundles. After autoclaving, a time-dependent distension, swelling and amalgamation of the fibrillary matrix was observed. This denaturation of the organic matrix was more pronounced after 5 min than 3 min autoclaving. The alterations of the fibrillary structure described above might be due to a preservation- and sterilization-induced decrease of the biological and biomechanical potential of bone grafts.

Collagen derived biomaterials have been used in medicine for ages. Intact, native collagen fibrils can be prepared in high purity from bovine tendons by pepsin treatment. Formulation of foils and sponges by freeze-drying is an accepted procedure. In the body, collagen is resorbed by an active cellular mechanism. Porous collagen sponges serve as carriers for the fibrin adhesive system. In Germany, these materials are used to control bleeding in parenchymatic organs. A gentamicin-collagen compound is clinically used in bone and soft tissue infections.

Wie bei jeder Organtransplantation besteht auch bei der allogenen Knochentransplantation das Risiko einer Krankheitsubertragung. Dieses Problems mussen sich der behandelnde Arzt und der Patient bewust sein. Auch bei Vorhegen negativer Blutkulturen findet sich bei bis zu 55% des postmortal unter aseptischen Operationsbedingungen entnommenen Knochens, der die Hauptquelle groser Knochenbanken darstellt, eine bakterielle Kontamination, die in etwa der Zusammensetzung der normalen Hautflora entspricht (Martinez et al. 1985). Ein groser Anteil des Spenderknochens mus somit verworfen werden. Ferner ist die Knochentransplantation im Zuge der aufgetretenen HIV-Problematik vermehrt Gegenstand der offentlichen Diskussion geworden. Verschiedene Kliniken sind sogar dazu ubergegangen, die allogene Knochentransplantation einzustellen. Bei entsprechendem, den Richtlinien der American Association of Tissue Banks entsprechendem Spenderscreening kann das Risiko einer HIV-Infektionsubertragung als beinahe vernachlassigbar gering angesehen werden. Um aber ein bestehendes Restrisiko fur serologisch nicht erfasbare Krankheiten, wie beispielsweise die Hepatitis Non A NonB auszuschliesen, kann eine Sterilisation der Transplantate notwendig werden. Nachdem bereits eine Reihe von Untersuchungen zu den biomechanischen Eigenschaften konservierten oder sterilisierten Bankknochens vorliegen, war es das vorrangige Ziel dieser Arbeit, Kenntnisse uber das strukturelle Verhalten von Knochen nach kombinierter Anwendung von Sterilisations- und Konservierungsverfahren zu gewinnen.