Stability of Implants Supported By Three Types of Bone Grafting Materials in Dogs

Background: This study was conducted to assess the stability of implants placed in a simultaneous procedure with different grafting materials (autogenous, xenogenous, and synthetic) in experimentally induced bone defects in dogs.Methods: Thirteen dogs were included and divided into three groups according to the time of sacrificing. Oversized osteotomies were prepared in the sternum, and the implants were placed in bone defects. A total of 3 to 5 implants were placed per animal. Each group of animals contained 3 subgroups according to the grafting material utilized. In subgroup 1, autograft was applied, whereas in subgroups 2 and 3, bovine bone mineral (Cerabone) and a synthetic calcium phosphate substitute (Osteon II) were employed. At the end of the specified healing periods (2 months, 4 months, or 6 months), the animals were sacrificed and the implant stability was determined through measuring the resonance frequency.Results: Forty-five integrated implants were obtained from this study and nine were lost (failure rate 17%). The two-way analysis of variance revealed no significant difference in ISQ measurements either between the bone graft materials (autogenous, xenogenous, and synthetic; P=0.950) or between the healing intervals (2 months, 4 months, and 6 months; P=0.769)Conclusions: The stability of implants augmented with autogenous, xenogenous (Cerabone) or synthetic (Osteon II) graft materials was comparable at 2, 4 and 6 months after placement. This indicates that both Cerabone and Osteon II could be considered as suitable substitutes for regeneration of bone defects to overcome the limitations of autografts.

So-called bifocal tumors with diabetes insipidus and negative tumor markers: are they all germinoma?

Background The Delphi consensus statements on the management of germ cell tumors (GCTs) failed to reach agreements on the statement that the cases with (i) pineal and neurohypophyseal bifocal lesion, (ii) with diabetes insipidus, and (iii) with negative tumor markers can be diagnosed as germinoma without histological verification. To answer this, multicenter retrospective analysis was performed. Methods A questionnaire on clinical findings, histological diagnosis, and details of surgical procedures was sent to 86 neurosurgical and 35 pediatrics departments in Japan. Results Fifty-one institutes reported 132 cases that fulfilled the 3 criteria. Tissue sampling was performed in 91 cases from pineal (n = 44), neurohypophyseal (n = 32), both (n = 6), and distant (n = 9) lesions. Histological diagnosis was established in 89 cases: pure germinoma or germinoma with syncytiotrophoblastic giant cells in 82 (92.1%) cases, germinoma and mature teratoma in 2 cases, and granulomatous inflammation in 2 cases. Histological diagnosis was not established in 2 cases. Although no tumors other than GCTs were identified, 3 (3.4%) patients had non-germinomatous GCTs (NGGCTs). None of the patients developed permanent complications after endoscopic or stereotactic biopsy. Thirty-nine patients underwent simultaneous procedure for acute hydrocephalus without permanent complications, and hydrocephalus was controlled in 94.9% of them. Conclusion All patients who fulfilled the 3 criteria had GCTs or granulomatous inflammation, but not other types of tumors. However, no fewer than 3.4% of the patients had NGGCTs. Considering the safety and the effects of simultaneous procedures for acute hydrocephalus, biopsy was recommended in such patients.

Simultaneous Bilateral Joint Arthroplasties in Treatment of Osteoarthritis

Osteoarthrosis is the most common chronic joint condition, the aetiology of which is still not completely clear. Initial phases of disease are treated conservatively applying physical rehabilitation procedures and medications. Advanced stages need surgical treatment with numerous procedures, depending on the joint affected. Joint arthroplasties are procedure of choice, especially for big joints of the extremities. As osteoarthrosis occurs bilaterally very frequently, there are a growing number of patients in need for operation of both joints. Those procedures can be performed under single anaesthesia or staged procedure, with delay between two surgeries. There are many advantages and disadvantages of both approaches cited by different authors. There is consensus of authors in available articles regarding benefits of single-stage procedure: lower cost, shorter hospital stay, single rehabilitation period and better functional results. Authors disagree about safety of a single-stage bilateral procedure as well as incidence of complications and criteria for selection of patients for safe performing of simultaneous procedure.

Simultaneous resection of abdominal aortic aneurysm and left renal cell carcinoma: A rare case and review of the literature

We report a rare case of concomitant abdominal aortic aneurysm (AAA) and left renal cell carcinoma (RCC). The patient was an 81-year old man who presented with vague abdominal pain. The investigations revealed a 110*73*62 mm AAA together with 69*56 left renal mass. Open repair of AAA with left radical nephrectomy was conducted. A simultaneous procedure is safe and does not increase morbidity and mortality in selected cases.

Improving judgment accuracy by sequential adjustment

Judging an object’s value based on relevant cues can be challenging. We propose a simple method to improve judgment accuracy: Instead of estimating a value after seeing all available cues simultaneously, individuals view cues sequentially, one after another, making and adjusting their estimate at each step. The sequential procedure may alleviate computational difficulties in cue integration, leading to higher judgment accuracy. We tested this hypothesis in two real-world tasks in which participants judged either the price of diamonds or the fuel economy of cars. Two studies with professional jewelers and car salespeople show that most participants indeed judged more accurately with a sequential than with a simultaneous procedure. Another two studies with college students further support this finding and show additionally that the sequential procedure could raise the judgment accuracy of inexperienced students to the same level as that of professionals judging with the simultaneous procedure.

Simultaneous surgery for primary and nodes in carcinoma penis: a rural tertiary medical centre experience and results

Background: Historically surgery for nodes in carcinoma penis was done as staged procedure due to fear of higher morbidity and longer hospital stay. However, in view of the established safety of the simultaneous procedure, very few centres do simultaneous surgery for nodes and primary in cancer penis.Methods: A retrospective analysis of all the simultaneous surgeries for nodes and primary for carcinoma penis done at our hospital, during the period April 2015 to March 2017 were done and various parameters were calculated and compared with historical standards of various series.Results: The various parameters namely wound morbidity, hospital stay and complications were analysed and compared with historical standards. A total of 15 patients during the above mentioned were found to be suitable for the analysis after having excluded patients who had previous therapy and inoperable tumours. The mean follows up period was 12 months (ranging from 8 to 20 months). The mean hospital stay was 15 days (range from 12 days to 25 days). The skin margin necrosis rate was 6.67%, wound infection rate was 6.67% and there were no perioperative deaths. The same was compared with historical standards.Conclusions: Simultaneous surgery for primary and nodes in carcinoma penis is safe and the standard results are reproducible in a rural tertiary medical centre like ours.

Estimating the reliability of eyewitness identifications from police lineups

Laboratory-based mock crime studies have often been interpreted to mean that (i) eyewitness confidence in an identification made from a lineup is a weak indicator of accuracy and (ii) sequential lineups are diagnostically superior to traditional simultaneous lineups. Largely as a result, juries are increasingly encouraged to disregard eyewitness confidence, and up to 30% of law enforcement agencies in the United States have adopted the sequential procedure. We conducted a field study of actual eyewitnesses who were assigned to simultaneous or sequential photo lineups in the Houston Police Department over a 1-y period. Identifications were made using a three-point confidence scale, and a signal detection model was used to analyze and interpret the results. Our findings suggest that (i) confidence in an eyewitness identification from a fair lineup is a highly reliable indicator of accuracy and (ii) if there is any difference in diagnostic accuracy between the two lineup formats, it likely favors the simultaneous procedure.

Bilateral Simultaneous Total Knee Arthroplasty: A Patient-Matched Retrospective Observational Study

Bilateral total knee arthroplasty can be performed either as a staged or simultaneous procedure. We conducted a retrospective comparative study to compare the need for transfusion, the length of procedure, the length of stay, and complications of bilateral simultaneous knee arthroplasty with those of unilateral knee arthroplasty. Sixty-nine patients who underwent bilateral simultaneous knee arthroplasty procedures were compared with a matched control group of 69 patients who underwent unilateral knee arthroplasty. Receiver Operating Characteristic (ROC) curve was used to determine optimum cut-off values. Both groups of patients had a similar age and gender distribution, preoperative haemoglobin and ASA scores. Cumulative transfusion episodes were lower in the bilateral group than twice that of the unilateral group. In multivariate analysis the preoperative haemoglobin level and bilateral procedures were independent factors predicting the need for transfusion. The average length of procedure and length of hospital stay in the bilateral group was less than twice than that of the unilateral group. Advanced age and bilateral procedures were independent predictors of prolonged length of stay. A haemoglobin level of 12.5 g/dL and age of 70 were most suitable cut-off points to predict need for transfusion and occurrence of medical complications respectively. We conclude that bilateral simultaneous knee arthroplasties are safe and cost effective in appropriately selected patients. We recommend avoiding bilateral simultaneous procedures in patients over the age of 70 years and with significant comorbidities.

On the Selection of Arbitrators

A key feature of arbitration is the possibility for conflicting parties to participate in the selection of the arbitrator, the individual who will rule the case. We analyze this problem of the selection of arbitrators from the perspective of implementation theory. In particular, theoretical analyses document problems with veto-rank—a simultaneous procedure commonly used in practice—and develop a new sequential procedure—shortlisting—with better properties. Experimental results are consistent with the theoretical predictions, highlighting both the disadvantages associated with the veto-rank procedure and the advantages associated with the shortlisting procedure. (JEL D71, D72)