Almost any kind of bacteria can be involved in prosthetic joint infections (PJI).

In 2014 we collected data on 3 patients presenting with hip or knee pain and radiological signs of prosthetic joint mobilization without any other clinical or biochemical suspect of infection.

Interestingly, in all cases we isolated bacteria very rarely involved in human infections: Cupriavidus pauculus, Ralstonia paucula and Neisseria flavescens. Both Cupriavidus pauculus and Ralstonia paucula are Gram negative environmental bacteria which can contaminate water (tap, pool and mineral) and have been isolated from a variety of human clinical sources including blood, wounds, sputum, urine, eye, throat and peritoneal fluid, as non pathogenic flora. In such two patients we were able to cure the infection with quinolones (both strains were sensible). Neisseria species are Gram-negative bacteria included among the proteobacteria. Neisseria flavescens is often found in the upper respiratory tract and oropharynx of humans, rarely associated with infectious process (necrotizing pneumonia and empyema). In this last patient we successfully used piperacillin-tazobactam i.v. during hospitalization and shifted to amoxicillin-clavulanate per os at discharge.

In conclusion, any bacteria can induce PJI: in some cases pre-operative blood tests are normal and therefore useless. We need new tests to overcome this diagnostic problem (such as alpha-defensin) and we must check on rare bacteria prolonging incubation to a more extended period of time (as in Propionebacterium acnes or Mycobacterium spp) and/or sending samples to specialized laboratories.

We thank all the medical and nurse staff of Prosthetic Joint Replacement Unit of Orthopaedic Center, Humanitas Research Hospital

Background: This report presents the long term (over 20 years) experience with the use of a grit-blasted, press-fit femoral prosthesis.

Methods: The first 300 consecutive primary THA procedures using a collarless, three-dimensional tapered, straight, titanium alloy stem with a grit-blasted surface (performed in 299 patients) were evaluated up to twentytwo years. A cementless all-polyethylene socket in 80 percent of the cases, were used. Radiographic evaluation, performed by an independent observer using a zonal analysis method, included assessment of component migration, Engh’s implant-bone femoral fixation score, implant-bone demarcations, and periprosthetic osteolysis. The average duration of long-term radiographic follow-up was 12.6 years (range; 10 to 16 years).

Results: At last examination only five hips were lost to follow-up and 84 patients were deceased. The femoral revision rate was 7 percent (two hips for aseptic loosening, five hips for septic loosening, and twelve hips with osseointegrated stems for severe progressive femoral osteolysis) and the acetabular revision rate was 28% (revised for either socket migration or progressive peri-acetabular osteolysis or both). Survivorship, based on any revision (femoral or acetabular) was 89% at ten years and 65% at twenty years; survivorship of the femoral component was 95% at ten years and 89% at twenty years. The incidence of femoral periprosthetic osteolysis, was 47%, with 5% of distal endosteal osteolysis. Radiographic femoral implant-bone fixation was stable, bone-ongrowth in 97%; stable, fibrous-fixation in 1%.

Conclusions: The grit-blasted, press-fit, collarless, tapered femoral component continued to perform well clinically and radiographically up to twenty years of follow-up despite the challenging environment of peri-prosthetic osteolysis associated with the acetabular component design. This implant is still in use virtually without design modifications. This study demonstrates the durability of the results of the grit-blasted femoral component and indicates that such an implant offers a viable alternative for fixation without bone cement.

Background. Total hip replacement (THR) has become the ideal treatment for any disorder causing joint destruction. Surgery-related infections are reported only in 1–2 % of THR, but antibiotic prophylaxis is necessary because infections are associated with significant morbidity and occasionally death. 1st and 2nd –generation cephalosporin or, in hospital with methicillin-R Staphylococcus spp (MRSA, MRSE) high prevalence, vancomycin, are the most frequently drug emplojed. The most frequent side effects of antibiotic prophylaxis are allergic reaction and pseudomembranous enterocolitis.

The objective of the present study was to assess the efficacy and tolerability of antibiotic prophylaxis for THR at S. Corona Hospital Pietra Ligure SV (Italy).

In our hospital the majority of prostethic device infections are due to MRSA, but recently we have described increment of infection due to Pseudomonas spp and other gram-. For this reason we used association of vancomycin plus pefloxacin in primary prophylaxis.

Methods. Retrospective analysis of 1118 THR performed in the period 2003–2004, receiving surgical prophylaxis with a single dose of the association vancomycin 1000 mg plus pefloxacin 400 mg. Data collection regarded patients’ age at surgery and reasons for THR. The presence of a surgery-related infection was investigated by means of a phone interview about the function of the hip device (presence of pain, deambulation impairment, fever). Patients with pain or other problems were submitted to physical exam, laboratory tests, plain radiograph and if necessary to exclude of infection, radioisotopic scans.

Results. We report the preliminary data on 218 THR in 211 patients (81 M, 122 F, median age 67.49 aa, range 29–91). THR was performed for: osteoarthrites in 168 cases, trauma in 26, osteonecrosis in 9, displasia in 4 cases, previous osteotomy in 4. 167/211 patients were submitted to a phone interview and 44 to a clinical examination.

Conclusions. In our center, the association of vancomycin-pefloxacin resulted effective and well tolerated as single dose prophylaxis for THR.

Introduction: Discomfort and pain are common but unspecific symptoms in orthopaedic prosthetics. The majority of these symptoms are secondary to mechanical failure or loosening, while only a small proportion is related to infection. The differentiation between synovitis, loosening or infection is important for a correct therapeutical management, but it is often difficult using noninvasive techniques.

Positron emission tomography (PET) with 2-deoxy-2-[18F]fluoro-D-glucose (FDG) has evolved from a research imaging modality to a clinical practice for the assessment of malignancies. FDG, a nonspecific tracer of increased intracellular glucose metabolism, has been found to accumulate not only in malignant cells but also in infection and inflammation foci.

Aim of the study was to evaluate the usefulness of FDG PET scan in patients with joint replacement.

Materials and Methods: In this study we describe PET findings in 33 patients (age 42–88 yrs.) with hips (n. 16) and knees (n. 17) prostheses who had a complete operative and/or clinical follow-up; 42.5% had a pattern of mobilization. All patients underwent PET scan 60 minutes after i.v. injection of 185 MBq of 18F-FDG (transmission-emission, 3D acquisition). PET tomograms were evaluated by nuclear physicians without knowledge of the clinical diagnosis by visual interpretation, which was graded on a four-point scale according with common clinical classification (0 = normal pattern: not significant locoregional uptake; 1 = synovitis: synovial localized uptake; 2 = prosthesis loosening: synovial and soft tissues uptake; 3 = prosthesis infection: synovial, soft and bone tissues diffuse uptake).

Results: The results will be discussed in detail and correlated with clinical findings. The diagnostic value of PET, in terms of sensitivity, specificity and accuracy was compared with traditional radionuclear techniques (dynamic bone scan, 99mTc-labelled granulocytes).

Conclusion: We underline a good correlation between PET and clinical pattern (88% of cases). Particularly PET was able to correctly differentiate the prostheses loosening in the 100% of cases without infection and in the 77% of patients with infectious disease suggesting its usefulness in clinical practice also for detecting only inflammatory tissue such as synovitis. Moreover, the capability of PET to quantificate the inflammatory activity could be useful in the monitoring of the therapy. Further evaluation in a large group of patients is indicated.

Adolescent idiopathic scoliosis is known to aggregate within families; however, the pattern of inherited susceptibility is unclear. A genomic screen and statistical linkage analysis of a genetic isolate including individuals with idiopathic scoliosis is being performed to identify variants responsible for this disease.

Scoliosis does not demonstrate a characteristic pattern of classical genetic (inherited) disorders. The severity of the disease within families can change and sometimes generations are skipped. However, the role of hereditary or genetic factors in the development of this condition is widely accepted. Numerous investigators are currently attempting to locate these genes. Studies based on a wide variety of populations have suggested an autosomal dominant mode of inheritance or sex-linked inheritance pattern. Other authors state that the “genetics link” may be complex, with an interaction of several genes rather than just one.

To identify chromosomal loci encoding genes involved in susceptibility to idiopathic scoliosis and the trasmission way of scoliosis we are studing a genetic isolate. We have generated a 10,600 individual pedigree of the village of Campora, in the Cilento area, starting from the beginning of the 17th century connecting all the 1200 living inhabitants. The actual population of Campora derives from a few founders; therefore, the living inhabitants are all related to each other. The population will undergo clinical and radiographic evaluation for the presence and degree of scoliosis. A genomic screen and statistical linkage analysis of the families with individuals having idiopathic scoliosis will be performed. With this approach we can identify variants responsible for this complex disease and genetic links of scoliosis.