Study of the motion artefacts of skin-mounted inertial sensors under different attachment conditions

A common problem shared by accelerometers, inertial sensors and any motion measurement method based on skin-mounted sensors is the movement of the soft tissues covering the bones. The aim of this work is to propose a method for the validation of the attachment of skin-mounted sensors. A second-order (mass-spring-damper) model was proposed to characterize the behaviour of the soft tissue between the bone and the sensor. Three sets of experiments were performed. In the first one, different procedures to excite the system were evaluated to select an adequate excitation stimulus. In the second one, the selected stimulus was applied under varying attachment conditions while the third experiment was used to test the model. The heel drop was chosen as the excitation method because it showed lower variability and could discriminate between different attachment conditions. There was, in agreement with the model, a trend to increase the natural frequency of the system with decreasing accelerometer mass. An important result is the development of a standard procedure to test the bandwidth of skin-mounted inertial sensors, such as accelerometers mounted on the skin or markers heavier than a few grams.     

Efficacy of extended thrombo-prophylaxis in major abdominal surgery: what does the evidence show? A meta-analysis

Venous thromboembolism (VTE) is a frequent complication following major abdominal surgery. The use of low-molecular-weight heparins (LMWH) to prevent thrombotic events in these patients is a common and well documented practice. However, there is some controversy surrounding the duration of the prophylaxis, as it has been suggested that the risk persists for several weeks after surgery. The objective of this meta-analysis is to systematically review the clinical studies that compared safety and efficacy of extended use of LMWH (for three to four weeks after surgery) versus conventional in-hospital prophylaxis. An electronic data base search was performed. Only randomized, controlled studies were eligible. Data on the incidence of deep vein thrombosis (DVT), VTE and bleeding were extracted. Only three studies fulfilled the inclusion criteria. The indication for surgery was neoplastic disease in 70.6% (780/1104) of patients. The administration of extended LMWH prophylaxis significantly reduced the incidence of VTE, 5.93% (23/388) versus 13.6% (55/405), RR 0.44 (CI 95% 0.28 - 0.7); DVT 5.93% (23/388) versus 12.9% (52/402), RR 0.46 (CI 95% 0.29 - 0.74); proximal DVT 1% (4/388) versus 4.72% (19/402), RR 0.24 (CI 95% 0.09 - 0.67). We found no significant difference in major or minor bleeding between the two groups: 3.85% (21/545) in the extended thrombo-prophylaxis (ETP) group versus 3.48% (19/559) in the conventional prophylaxis group; RR 1.12 (CI 95% 0.61 - 2.06). There was no heterogeneity between the studies. We conclude that ETP with LMWH should be considered as a safe and useful strategy to prevent VTE in high-risk major abdominal surgery.     

Fracture of the penis: a case series

Penile fracture is an uncommon urological emergency with a typical presentation, which needs early surgery to avoid aesthetic and functional sequelaes. We have analyzed all the patients with a discharge diagnosis of fractures penis among 1997 to 2007, attended in the emergency service of Complejo Hospitalario Universitario de Albacete, showing its clinical features, attributed mechanism of injury, treatment and main complications.     

Videothorascocopic: approach in thoracic inlet of neurogenic mediastinal tumor in pediatric age

We present a 4 year-old patient with precedent of pneumonia and showing an increase of X-ray density in the superior mediastinal. After a year of follow-up and the presence of irritating cough, it is decided to perform studies of image (CT), being diagnosed of a mass in the region of the thoracic inlet which affects up to D4. Video-assisted thoracic surgery is decided and the mass is entirely removed, being the result of the pathological study to ganglioneuroma. Eight months later from, the patient is asymptomatic and without relapse according to the image methods which were carried out.