Biomechanical comparison of stemless humeral components in total shoulder arthroplasty

BackgroundThe purpose of this study was to compare initial fixation strength between various stemless and stemmed humeral components and to correlate implant fixation strength with bone mineral density (BMD).MethodsFive humeral stem designs were investigated: Stemless-A (four hollow fins), Stemless-B (central body, three solid fins), Stemless-C (central screw, peripheral rim-fit), Short stem (50 mm), and Standard stem (130 mm). Fifty cadaveric human humerii were obtained and divided into five groups. BMD within the humeral head was determined for all samples. The mean BMD was similar between groups. The 25 samples with the lowest and highest BMDs were categorized as “Low” and “High,” respectively, with a BMD threshold of 0.35 g/cm², creating BMD subgroups. After implantation, each sample underwent a standardized biomechanical testing protocol, with axial loading followed by torsional loading. Sensors attached to the specimen recorded micromotion throughout testing. Axial loading consisted of cyclic loading for 100 cycles at 3 peak forces (220, 520, and 820 N). Torsional loading consisted of 100 cycles of internal/external rotation at 0.1 Hz at 6 peak torques, or until failure (±2.5, 5, 7.5, 10, 12.5, and 15 Nm). Failure was defined as the torque at which any bone fracture, implant detachment from anchor/stem, or an excess of 50° internal/external rotation occurred. Groups and BMD subgroups were compared.ResultsAt maximal axial loading, Stemless-B demonstrated greater micromotion (540 μm) than Stemless-C (192 μm) (P = .003). Stemless-B and Stemless-A (387 μm) also had greater micromotion than Short stem (118 μm, P < .001, P = .03) and Standard stem (85 μm, P < .001, P = .01). When comparing low-BMD samples at maximal axial loading, these differences were accentuated, but comparison of high-BMD samples showed no significant differences between groups. Torsional testing demonstrated that Standard stem failed at greater torque (7.2 Nm) than Stemless-B (2.3 Nm, P < .001), Stemless-A (1.9 Nm, P < .001), and Stemless-C (3.9 Nm, P = .01). When comparing torsional testing results of low-BMD samples, both Standard stem and Short stem failed at greater torque than Stemless-B (P = .02, P = .003) and Stemless-A (P = .03, P = .004) but failed at a similar torque to Stemless-C. Torsional testing of high-BMD samples showed that Standard stem failed at a greater torque than all stemless designs.ConclusionStemless humeral implants should be used with caution in low-BMD settings (<0.35 g/cm²). A central screw and peripheral rim-fit stemless anchor design demonstrated greater fixation strength at low BMD when compared with other designs, while all stemless designs performed similarly at high BMD.Level of evidenceBasic Science Study; Cadaveric Study     

The impact of age on prognosis in patients with gastric cancer: experience in a tertiary care centre

BackgroundGastric cancer (GC) is a leading cause of cancer-related death in the world and most patients have advanced disease upon presentation. The effect of age on prognosis in GC is controversial. We aimed to determine the impact of age on survival in patients with GC.MethodsThis was a retrospective study of the medical records of Lebanese patients diagnosed with GC at the American University of Beirut Medical Center (AUBMC) between 2005 and 2014. Patients were divided into young (<65 years) and older groups (≥65 years). A multivariate analysis was done to determine the independent predictors of survival. Kaplan-Meier method was used for analysis of long-term survival outcomes.ResultsThe sample consisted of 156 patients. The mean age was 62.15 (SD 13.54). Most patients presented with stage 4 disease (62.2%) and poorly differentiated histology (66.4%). The most common symptoms were abdominal pain and weight loss. On bivariate analysis, advanced stage (P=0.02) and higher grade (P=0.04) were associated with increased mortality. Patients <65 years of age were significantly more likely to have poorly differentiated tumours, while patients ≥65 years had more comorbidities (P=0.001). The 5-year DFS were 35% and 37% for patients <65 years of age and ≥65 years of age, respectively (P=0.15).ConclusionsHigher grade and advanced stage are associated with worse survival in patients with GC, but age did not seem to have an impact. Screening high risk patients and early diagnosis are necessary to improve survival.     

Evaluation of the bioequivalence and food effect on the bioavailability of CC-486 (oral azacitidine) tablets in adult patients with cancer

Cancer Chemotherapy and Pharmacology - CC-486 is an oral formulation of azacitidine that allows for extended dosing schedules to prolong azacitidine exposure to malignant cells and maximize...     

Pattern of Venous Thrombosis in Cancer Patients: Frequency and Survival Effect; Single Center Experience

Venous thromboembolism (VTE) represents one of the most important causes of morbidity and mortality in cancer patients. This investigation was undertaken to investigate the natural history of VTE in the oncology center in a tertiary care hospital. We did a retrospective study on cancer patients who presented to King Abdullah Medical city in Holly capital; a tertiary care hospital; from May 2011 to June 2013. Follow up period was calculated from time of VTE diagnosis till the last clinical visit or till patient death. Among 1,678 cancer patients, 132 (7.87 %) were diagnosed with VTE. The median patient age was 53.5 years, with female to male ratio 1.3/1. Thirty one patients (23.5 %) were diagnosed with VTE and cancer simultaneously, seventy four patients (56.1 %) were on chemotherapy and twenty eight patients (21.2 %) were on best supportive care.VTE were symptomatic in 110 patients (83.3 %) and asymptomatic in 22 patients (16.7 %). Lower limbs were the commonest site (42.4 %) with the highest incidence in patients with advanced stages (93 %). Forty nine (37 %) patients were receiving LMWH as prophylaxis. Median survival in months for patients with VTE prophylaxis versus without prophylactic, and asymptomatic versus symptomatic were (12.6 vs 6.3; p 0.12 and 9.8 vs 12.4; p 0.885, respectively). There is underutilization of thromboprophylaxis in our region, which needs more effort to reduce VTE burden. Also we need large prospective studies to clarify the impact of VTE symptoms and presentation on patient’s survival.     

Development,implementation, and evaluation of an integrated multidisciplinary Objective Structured Clinical Examination (OSCE) in primary health care settings within limited resources

Background: In ordinary circumstances, objective structured clinical examination (OSCE) is a resource-intensive assessment method. In case of developing and implementing multidisciplinary OSCE, there is no doubt that the cost will be greater.

Aim: Through this study a research project was conducted to develop, implement and evaluate a multidisciplinary OSCE model within limited resources.

Methods: This research project went through the steps of blueprinting, station writing, resources reallocation, implementation and finally evaluation.

Results: The developed model was implemented in the Primary Health Care (PHC) program which is one of the pillars of the Community-Based undergraduate curriculum of the Faculty of Medicine, Suez Canal University (FOM-SCU). Data for evaluation of the implemented OSCE model were derived from two resources. First, feedback of the students and assessors through self-administered questionnaires was obtained. Second, evaluation of the OSCE psychometrics was done. The deliverables of this research project included a set of validated integrated multi-disciplinary and low cost OSCE stations with an estimated reliability index of 0.6.

Conclusion: After having this experience, we have a critical mass of faculty members trained on blueprinting and station writing and a group of trained assessors, facilitators and role players. Also there is a state of awareness among students on how to proceed in this type of OSCE which renders future implementation more feasible.     

Spontaneous resolution of plastic bronchitis in a patient post hemi-Mustard/bidirectional Glenn atrial switch procedure in the double-switch operation for congenitally corrected transposition of great arteries after course of Augmentin

We report the case of a five-year-old girl with plastic bronchitis after repaired complex congenital heart disease, who became asymptomatic after a short course of Augmentin. We report the disease regression as response either to antibiotic or as coincidental with spontaneous resolution.