Aim

Prosthetic joint infections (PJI) after failed knee arthroplasty, especially in complicated courses with persisting or recurrent infections, may result in a considerable destruction of bone substance, the extensor apparatus and the surrounding soft tissue. In these cases reconstruction of a proper knee function may be impossible and the only solutions are: knee arthrodesis or above-the-knee amputation (AKA). However, both methods are associated with considerable functional deficits and high complication rates. The primary aim of the current study is to analyse the clinical course, outcome and complications in patients with knee arthrodesis and AKA after PJI and to compare these two methods in terms of the analysed parameters.

To prevent nosocomial transmission (NT) of multiresistent germs (MRG) the German Robert Koch Institute (RKI) recommends to isolate patients with MRG.

At a so-called normal ward isolating patients is a challenging and stressful procedure for both patients and hospital staff.

The present study proposes the hypothesis that, compared to normal wards, an isolation ward reduces the nosocomial infection rate.

After an isolation ward with twelve beds has been established in 2005, patients with MRG on the wards of the department for spinal cord injury as well as on the isolation ward were monitored using a prospective screening and meeting the requirements of the RKI. Apart from detecting transmitter of MRG the NT of these bacteria was identified and registered between 2006 and 2013.

The total length of a patients stay in the hospital, the number of isolation days and the rate of NTs were documented. The quotient of MRG load per ward and the number of NTs per ward were compared.

In the investigation period of eight years 262175 patient days, 33416 isolation days and 33 transmissions were registered.

On the spinal cord injury ward 223167 of the patient days, 1120 of the isolation days and 29 of the NTs were documented. On the isolation ward 39008 of the patient days and 32296 of the isolation days with four of the transmissions were registered.

The mean load of MRG resulted from the quotient of the number of days with MRG per 100 patient days.

The effective nosocomial frequency of transmission resulted from the quotient of the mean load of MRG to the number of transmissions.

As a result, the frequency of transmission on the isolation ward was significantly lower (p=0,001) in comparison to the spinal cord injury ward.

The presented results suggest that, despite multiple higher loads of MRG, constructional measures combined with contact isolation facilitate a reduction of NT rates of MRG.

The reservation must be made, however, that in case of known MRG the screening was performed under isolation conditions, with unkown MRG without meeting requirements of isolation.

The present comparison of NT rates on an isolation ward and a normal spinal cord injury ward emphasizes the importance and function of an isolation ward through constructional (physical) separation and pooling of professional competency for successful management of MRG in healthcare facilities.

Introduction: Because of strong loads acting in the elbow joint, intraarticular fractures with a methaphyseal comminuted fracture site at the distal humerus demand a lot from the osteosynthetic care.

Ambiguities arise concerning to the anatomic position of the implants and the resulting mechanic performance.

Aim of this study was the comparison of three anatomic variations of one angle stable plate system as to their mechanic stability.

Material and Methods: As a fracture model an AO C 2.3-fracture on an artificial bone (4th Gen. Sawbone) was simulated via double osteotomy in sagittal and transversal plane. The fractures were equipped with a prototypical version of the Variax Elbow System (Stryker) in the variations 90° (lat+post), 90° (med+post) and 180° (med+lat).

A physiological load distribution (Capitulum Humeri 60%, Trochlea humeri 40%) could be guaranteed for by a therefore designed test set up. In three test series, the load to failure (static), the system rigidity (static) and the median fatigue limit (dynamic) were determined. The tests were conducted under 75° flexion and 5° extension and the relative displacements were recorded.

Results: In extension, the 180° (med+lat) alternative achieved the highest load to failure (2959 N), stiffness (1126 N ± 127 N) and median fatigue limit (1046 N ± 46 N) followed by the 90° (lat+post) alternative.

Great differences could be stated with the 180° (me d+lat) alternative in extension in comparison to the flexion (p< 0,05): under flexion the failure already appeared at 1077N and the stiffness reduced to 116 N ± 10 N. The highest stiffness (202 N ±19 N) under flexion load could be determined for 90° (med+post). As to stiffness, the 90° (lat+post) alt ernative lay in between. Decreases of fracture gaps due to a failure of screw bone interface and a bending of plates could be determined as failure patterns in case of static load. Under dynamic load especially fatigue fractures occurred at the implant system in terms of broken plates and screws.

Conclusion: In vivo the highest loads occur at the distal humerus in extension direction which can best be transferred, in static as well as in dynamic regard, by a 180° alternative. An alternative to that is the 90° (lat+post) variation due to its advantageous me chanic performance under static and dynamic extension load. But still the nature of fracture with size and position of the fragments useable remains decisive for the choice of an osteosynthesis.

The mechanic superiority of the 180° alternative (minimized gap displacement and high stiffness of the system respectively) in extension direction in comparison to a 90° alternative can be explained by the 90° position of the plates and hence reduced moment of inertia. Less stiffness under flexion direction arises from the long levers, which cause high bending moments.

Necrotizing fasciitis is a definition of a specific histopathology, the pathogenesis and clinical features vary broadly. Symptomatically is the severe invasive infection of the soft tissues with high rates of patient morbidity and mortality. Beside the most common identified bacteria as A Streptococci (GAS), other bacteria are identified such as gram-positive or-negative bacteria or mixed infections. The aim of the following study was to analyze the specific predisposing risk factors and outcome of patients suffering necrotizing fasciitis.

Methods: The data of patients suffering necrotizing fasciitis were prospective collected since 2004. Criteria were the clinical and histological evidence of a necrotizing fasciitis. The clinical course, concomitant diseases, detectable bacteria and outcome with focus on limb salvage, amputation rates and hospital mortality was analyzed. Primary focus of the therapeutic regimen was the surgical and intensive care therapy. Adjuvant therapy was the hyperbaric oxygen therapy.

Results: 55 patients were prospective enrolled in the study with the clinical and histological diagnosis of a necrotizing fasciitis from 2004–2008. The mean age of the patients was 58 ± 15 years at the timepoint af admission to the hospital. Gender distribution was 68 % male and 32 % female. 87 % of these patients were admitted after interhospital transfer. 82 % were admitted to the intensive care unit and 78 % needed catecholamines. The hospital mortality was 31 %. The ranking list of potential risk factors in descending frequency was: diabetes, obesity, immunosupression of different causes. Affected were in 22 % of the cases the upper extremities, 72 % lower extremities and/or in 12 % the trunk. In 80 % of the deceased patients the pelvic region or the trunk was involved. Almost half of the patients suffered an amputation of one limb.

Summary: The necrotizing fasciitis remains an interdisciplinary challenge for specialized centers providing the logistical infrastructure for the treatment of these patients. Despite the optimal treatment options and additional therapy with hyperbaric oxygen therapy the hospital mortality remains high. Prognostic unfavorable is the involvement of the trunk and pelvic region. Typical risk factors are described above. The analysis of pathogenic bacteria shows a broad variety and gives no clear hints in the diagnosis or prognosis of the fasciitis. Crucial for the surgery and indication for limb amputations as a salvage procedure is the clinical course.