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We identified 39 patients (23 female and 16 male) underwent hip revisions through mega-prosthesis. The most common causes were periprosthetic fractures, periprosthetic osteolysis and consequences of infected arthroplasty. The average follow-up was 5 years (2.1 to 6.5), and average age was 69 years (47 to 78). At the final follow-up all the implants resulted functional and osteointegrated. The Merle D’Aubignè and Postel hip rating scale was used for the evaluation, better results were observed in periprosthetic fractures. Postoperative complications occurred in eight patients. Thus, megaprosthesis were a reasonable surgical option in the management of major femoral defects.

To evaluate the clinical outcomes of patients treated with Girdlestone procedure (GP) or excision arthroplasty (EA) for periprosthetic infection with massive bone defects and undergoing revision arthroplasty.All patients treated with EA or GP for hip periprosthetic infection between 2014 and 2017 and sustaining revision arthroplasty (RA) were included in the study. Patients with less than 24 months of follow-up or less than 12 months between GP or EA and RA were excluded. Any sign of implant mobilization or periprosthetic fracture was assessed through X-ray. Patients were evaluated with D'aubignè-Postel hip score before RA and at the last follow-up. Mann-Whitney U test was used to assess differences between pre-RA surgery and last follow-up. P value was set as0.05.Twelve patients meet the inclusion criteria (mean follow-up 58+/-9.72 months). No radiographic sign of implant mobilization or periprosthetic fracture was reported. A significant difference was found for each parameter of the D'Aubigne-Postel score (p0.0001); none of the patients reached more than fair results in the absolute hip score. The difference between pre and post-operative global status showed a fair improvement. A significant difference was found for leg length discrepancy between pre and post RA (p0.0001).Conversion from EA or GP to RA in patients suffering from massive acetabular and femur defects is challenging; conversion procedure is able to reduce patients' disability and to improve walking ability. (www.actabiomedica.it).

Background Within a timeframe of 8 years (2008-2016), 38 patients have undergone total hip replacement surgery for coxarthrosis or aseptic necrosis secondary to acetabulum fractures. Materials and Methods The study included 27 males and 11 females between 42 and 70 years of age, all of whom came from other institutions. The follow-up period ranged between a minimum of 4.6 and a maximum of 9.7 years. Results At the final follow-up, all patients were evaluated using the Merle D’Aubigne and Pastel model. Optimal results were found in all the cases. Three patients benefited from surgical revisitation with implant exchange following infection and one/two state reimplatation at seven, fourtheen et twenty-seven months respectively. Two patients benefited from cotyle revision due to chronic instability of the implant. Conclusions The scope of the study was to present all the possible surgical difficulties that can come up with prosthetic implants. More particularly, hip implants after acetabulum fractures qualifies as a “difficult primary implant”.

BACKGROUND Surgical treatment of complex fractures of the distal femur in the elderly is controversial. Osteoporosis and pre-existent osteoarthritis are common comorbidities in the elderly which add to the need for early walking and rapid restoration of function and also pose significant obstacles to achievement of satisfactory results with standard fixation techniques. Recently, several authors have suggested that primary arthroplasty could be a viable alternative option to standard fixation techniques in selected patients with complex distal femur fractures. AIM To present our experience with 11 cases of distal femur fractures treated with knee arthroplasty and large femoral resection in a population of patients over the age of 85. METHODS Data from 11 consecutive patients (10 females, 1 male) presenting with acute intra-articular supracondylar or intercondylar distal femur fractures and with pre-existent primary osteoarthritis who were treated with primary knee arthroplasty were recorded. We collected standard demographic data, comorbidities and patient reported outcomes including Visual Analogical Scale (VAS), Oxford Knee Score (OKS) and Barthel’s Index. Post-operative joint range of motion (ROM) and standard radiographic data were also collected. RESULTS At a mean follow-up of 23.2 mo, all of the implants were well-positioned and osteointegrated. Furthermore, all the patients were alive and walking either independently or with walking aids. There was a marked improvement in pain (VAS 4.5 postop vs 1.9 at the last follow-up), OKS score (29.5 postop vs 36.81 at the last follow-up), ROM (96.2° postop vs 102° at the last follow-up) and restoration of pre-injury ambulatory status (average Barthel Index 77.3). The radiographic evaluations showed good restoration of the articular geometry. No deaths and no complications were recorded. CONCLUSION In conclusion, we believe that knee megaprosthesis in the case of complex fractures of the distal femur is a valid surgical choice. This is particularly true in elderly patients with severe osteoporosis and pre-existing osteoarthritis. It is important to note that this surgery should be performed by surgeons with proven experience in prosthetic hip and knee surgery and that a scrupulous selection of the cases is completed.

According to the European Community Regulation 1139/2003, a sampling plan based on an appropriate tests to detect the presence of central nervous system (CNS) tissue on the surface of the head muscles had to be implemented in each member state starting from 2003. In previous studies, we showed a medium CNS contamination in head meat from Italian slaughterhouses of 14,7%. Recently, German authors referred about alarming rates (82%) of CNS contamination in para-vertebral muscles after routine carcass splitting and spinal cord removal practices. In that context, the authors intended to assess the percentage of CNS contamination in muscles close to the vertebral column obtained by applying three different removal practices of specific risk material (SRM). Two alternative techniques, by sucking out and by water-jet, were compared to the traditional one; in both situations the removal of spinal cord occurred before the carcass splitting. The percentage of contamination resulted 62% applying the traditional technique, 60% with the sucking out system and 36% using the water-jet. The results show that water-jet ensures the most significant reduction of SRM contamination in para-vertebral meat as it guarantees a rapid and complete extraction of the spinal cord.

This paper proposes a new time scaled Wiener process with random effects that has been specially designed to allow the description of non-monotonic degradation phenomena with bathtub shaped degradation rate, here intended as derivative of the mean function. Two different parameterizations of the proposed Wiener process are suggested, and the main features of the process are illustrated and discussed. Themaximum likelihood estimation of its parameters is addressed. A failure threshold model is adopted to formulate and estimate the probability distribution function of the remaining useful life, which constitutes the core prognostic tool in condition-based maintenance. As a motivating example, the proposed model is applied to a set of real degradation data of metal-oxide-semiconductor field-effect transistors, where, as a result of preliminary analyses, some of the process parameters are assumed to be random in order to describe the considerable heterogeneity observed between the degradation paths of different units. Obtained results demonstrate the affordability and utility of the proposed model, especially for the estimation of unit-specific features performed on the basis of degradation data collected in the early phase of the life of a unit belonging to the considered heterogeneous population.