Defining the pubic symphysis angle with respect to the coronal plane - Clinical and biomechanical considerations.

BACKGROUND: Fixation strength of constructs placed across the pubic symphysis after injury is dependent on screw length, maximisation of which requires knowledge of the bony anatomy. The aim of this study was to describe the ideal angle of drilling to achieve maximal safe screw placement within the pubic body. Furthermore, the influences of age and gender on the skeletal topography were investigated. METHODS: Three hundred CT scans of patients without pelvic injury were analysed to record the angle of the pubic body (APB) with respect to the coronal plane, and the depth of the pubic body (DPB) in the sagittal plane. RESULTS: Mean APB and DPB were 54.69° and 55.35mm, respectively. Females had a significantly higher mean APB than males (57.29° vs. 52.41°; p<0.001), whereas males had a significant larger mean DPB (59.13mm vs. 51.03mm; p<0.001). Age had no effect on the mean APB. Mean width of the pubic body at the base was 9.38mm. CONCLUSION: The anatomy of this region is reliable in terms of angles and sizes; a drill angle of 55° with respect to the operating table will allow maximal screw length, which should be in the region of 55mm. The mean width of the pubic body should allow for placement of a 3.5 or 4.5mm diameter screw.

Non-operative management of fingertip injuries with an intravenous dressing.

OBJECTIVE: The optimal management of fingertip injuries is a much debated topic. Surgical and nonsurgical options, including treatment with dressings alone, have comparable results. IV3000 is a semi-occlusive dressing with a high reactive moisture vapour transmission rate (MVTR) compared to its alternatives. As the fingertip is crucial to hand function, determining the optimal dressing to treat these injuries is of clinical importance. The aim of this study is to collect preliminary data on the IV dressing when used to treat fingertip injuries. METHOD: Patients were recruited from the department of orthopaedic surgery outpatient clinic. Inclusion criteria were a fingertip injury with skin loss and emergency department treatment consistent with the study protocol, including washing the fingertip, simple debridement as required, administration of antibiotics, tetanus prophylaxis, and fingertip dressed with the IV dressing. RESULTS: Fingertip injuries (15) from 13 male patients were identified. With the exception of one, all injuries were treated with the IV dressing and were included in the analysis. The treatment outcome of 13 injuries was rated as 'satisfactory' by the patients, while one was rated 'indifferent'. The latter was on one of two patients with injuries to two digits. No patient reported their outcome as 'unsatisfactory'. At the 18-24 months' follow-up, seven of the 14 affected digits had some degree of hypersensitivity, eight regained normal pulp thicknesses, one had thickened padding, and five had reduced pulp volume. All but one patient reported some degree of numbness. Nail involvement was seen in 11 injuries, all of which continued to have some degree of nail deformity. CONCLUSION: The IV dressing provides satisfactory outcomes when used to treat fingertip injuries. As the dressing possesses properties that suggest it would result in a superior healing environment compared to other semi-occlusive dressings, a prospective, randomised control trial should be conducted to determine whether these properties translate into superior outcomes when used to treat fingertip injuries.

Precore and basal core promoter mutations in Asian American patients with hepatitis B e antigen-positive chronic hepatitis B.

BACKGROUND: Prior studies have shown that precore mutations abolish and basal core promoter (BCP) mutations down-regulate hepatitis B e antigen (HBeAg) production. Thus, the presence of precore and BCP mutations in HBeAg-positive patients indicates an infection with a mixed viral population of wild-type and precore and/or BCP mutant hepatitis B virus (HBV). To date, there has been limited study of the prevalence and clinical significance of precore and BCP mutations in patients with HBeAg-positive chronic hepatitis B. AIM: To determine the prevalence, predictors and clinical characteristics of mixed wild-type and precore/BCP HBV infection, through a cross-sectional study, in a US cohort of patients with chronic hepatitis B. METHODS: We conducted a retrospective study of 828 chronic hepatitis B patients with HBV genotype and mutation panel testing seen at three US gastroenterology and liver clinics from June 2005 to September 2009. RESULTS: A majority of our patients (92.3%) were either Vietnamese or Chinese American. In the HBeAg-positive cohort, 17% of patients had precore mutations only, 28% had BCP mutations only and 5% had both BCP and precore mutations. On multivariate analyses, HBV genotype C, increasing age, lower HBV DNA level and an ALT quotient >2 were independent predictors for the presence of precore and/or BCP mutations. CONCLUSIONS: The current distinction and management recommendations for HBeAg-positive vs. HBeAg-negative patients with chronic hepatitis B should be reassessed. Additional biomarkers and treatment endpoints should be studied for their usefulness in predicting continued viral suppression after treatment discontinuation.

Prospective study of risk factors for hepatitis C virus acquisition by Caucasian, Hispanic, and Asian American patients.

Commonly known risk factors for infection with hepatitis C virus (HCV) include blood transfusion, injection drug use, intranasal cocaine use, and body tattoos. We hypothesized that Asian Americans infected with HCV may not identify with these established risk factors present in Caucasians and Hispanics, and our aim was to conduct a survey of risk factors in HCV-infected patients in these ethnic groups. In this prospective study, 494 patients infected with HCV completed a detailed risk assessment questionnaire at a liver centre in Northern California from 2001 to 2008. Among subjects participating in this study, 55% identified themselves as Caucasian, 20% as Hispanic, and 25% as Asian. Asian Americans were older, less likely to smoke or consume alcohol, and have a family history of cancer compared with Caucasians and Hispanics. The laboratory profiles were similar, and genotype 1 was the most common infection in all groups (74-75%). The great majority of Caucasians (94%) and Hispanics (86%) identified with commonly known risk factors, which was in contrast to 67% of Asians (P < 0.0001). The most common risk factors in Asians were blood transfusions (50%) and acupuncture (50%). Furthermore, 74% of Caucasians and 66% of Hispanics identified more than one major risk factor, while only 20% of Asians reported having more than one risk factor (P < 0.0001). Survey for established risk factors for acquisition of HCV may be more appropriate for risk assessment of Caucasians and Hispanics, but not for Asian Americans. These findings may guide the development of HCV screening in our increasingly diverse population.

One-dimensional pattern of Au nanodots by ion-beam sputtering: formation and mechanism.

Highly ordered one-dimensional arrays of nanodots, or nanobeads, are fabricated by forming nanoripples and nanodots in sequence, entirely by ion-beam sputtering (IBS) of Au(001). This demonstrates the capability of IBS for the fabrication of sophisticated nanostructures via hierarchical self-assembly. The intricate nanobead pattern ideally serves to identify the governing mechanisms for the pattern formation: nonlinear effects, especially local redeposition and surface-confined transport, are essential both for the formation and the preservation of the one-dimensional order of the nanobead pattern.