Elastic Rubber Band Research Articles

Active non-operative treatment of acute isolated posterior cruciate ligament injury with cylinder cast immobilization

The objective of our study was to investigate the outcome of an active non-operative treatment of the acute isolated posterior cruciate ligament (PCL) injury using cylinder cast immobilization and brace with tibial supporter. This study included 17 acute and isolated PCL injuries with two years or more of follow-up for each patient. We applied a cylinder cast immobilization with tibial supporter with full extension of the knee for 6 weeks, and then another 6 weeks of PCL brace with tibial supporter and posterior elastic rubber band to prevent posterior sagging of the proximal tibia. There was improved anteroposterior stability with some residual laxity and improved clinical results at the last follow-up. The conservative treatment utilizing cylinder cast immobilization and brace may be one of the recommendable treatment methods in an isolated and acute PCL injury.

Contention adhésive de cheville et contrôle postural en condition quasi statique : impact de la pose d’une sous-bande en mousse

Aim This study's purpose is to estimate the effect of an elastic rubber band ankle strapping on the postural control with or without underwrap. Method Fifteen healthy volunteers have been tested on a two feet standing position while performing a task under three conditions: without being strapped, with the strapping over the skin and with the strapping over and underwrap. The variable on trial, recorded using a force platform, was the pression center movement (CP) defined by its frontal (AP) and medial (ML) axes. We extracted CP trajectories decomposed into two elementary motions: the horizontal displacements of the centre of gravity (CG) and the vertical projection of the difference between centre of pressure and the centre of gravity (CP–CG). Results The only statistically significative decrease of variance from the no strapping condition was with over skin strapping condition for the CP and CG on ML axe. No CP–CG variance was significally modified. Conclusion The over skin strapping provide a lateral stabilization. The hypothesis of additional sensory information and mechanical restriction of the ankle could provide explanation.

Pseudolipomatose do cólon: relato de caso

A pseudolipomatose cólica é uma condição benigna, raramente descrita, caracterizada histologicamente pela presença de múltiplas vesículas contendo ar na parede do intestino grosso. Acredita-se que a doença tenha origem iatrogênica, ocasionada pela infiltração de ar através da mucosa cólica durante a realização de procedimentos endoscópicos. O objetivo do presente relato é apresentar um caso de pseudolipomatose cólica, confirmada por meio de estudo histopatológico e imunoistoquímico. Relato do caso: Mulher, 74 anos foi submetida à colonoscopia para investigação de anemia. Apresentava sangramento retal cíclico durante as evacuações, perda ponderal e anemia. O exame endoscópico não mostrou alterações do cólon, detectando apenas mamilo hemorroidário que no momento do exame apresentava sinais de sangramento recente. Três semanas após o exame foi submetida à ligadura elástica do mamilo hemorroidário. Durante a realização do procedimento encontrou-se área sobrelevada na mucosa intestinal, de coloração amarelo-esbranquiçada, com aproximadamente quatro centímetros de diâmetro, localizada na parede posterior do reto, a 13 cm da margem anal que inexistia quando da realização da colonoscopia. Foi realizada biópsia da região alterada da mucosa e ligadura elástica do mamilo hemorroidário. O exame histopatológico demonstrou a presença de inúmeros vacúolos de diâmetro variado, algumas vezes confluentes, localizados na lamina própria da parede intestinal mimetizando tecido adiposo. Notava-se ainda presença de pertuito longitudinal que comunicava a região vacuolizada com a superfície da mucosa cólica. As técnicas histoquímicas e imunoistoquímicas para detecção de gordura no interior das vesículas revelaram-se negativas, permitindo o diagnóstico de pseudolipomatose cólica. Após a ligadura elástica a enferma não mais apresentou sangramento retal, recuperando-se da anemia. Conclusão: A pseudolipomatose do cólon, apesar da raridade, é uma condição que pode ser encontrada após a realização de procedimentos endoscópicos no cólon.

Accuracy of Biodex system 3 pro computerized dynamometer in passive mode

A specific experimental design has been developed to determine the accuracy of the Biodex system 3 pro dynamometer in passive mode. Five cyclic stretching repetitions were imposed to an elastic rubber band at different velocities using the dynamometer, and the torque produced was measured using both the dynamometer and external force and position sensors. Velocity patterns performed by the dynamometer were also characterized and our results show that these patterns were reliable (ICC = 1.00). The torque measured with the dynamometer and the sensors were reliable (ICC = 1.00), although significant differences were observed between both methods. However, the measured torque standard error was velocity independent and was lower than 0.33 N m. Moreover, regressions between the two torque measurements were close to the axes-bisector ( r = 1.00, slope: 1.01 ± 0.01, y-intercept: −0.36 ± 0.22 N m). Finally, our results showed decreases in torque during the five cycles, but these decreases were not due to the dynamometer. It can be concluded that the dynamometer performed valid torque measurements in passive mode, and was an accurate tool to determine passive mechanical properties of the musculo-articular system. However, some discrepancies between the programmed and the measured speed profiles have been observed when approaching the speed limit of the system.

Experience with elastic rubber bands for the tie-over dressing in skin graft

We derived a dressing using elastic rubber bands to tie over the skin graft. This is a simple, easy to perform, timesaving, inexpensive and reliable method for applying pressure over the skin graft compared with traditional methods. Between September 2002 and August 2004, we have used the present dressing technique in 35 patients with 36 grafts in various parts of the body. We chose this method, because of some anatomic areas, such as back, and buttock, which are frequently quite difficult to maintain pressure dressings in place, minimal movement can cause the skin graft to dislodge. The elastic rubber bands, rather than threads, are used as tie-over. Such a dressing permits expansion and contraction, providing a dynamic quality in the most difficult anatomic locations. The patient group consisted of 23 males and 12 females. The age ranged from 34 to 82 years (mean 52.4 years). Defect size ranged from 3 × 2.5 to 30 × 20 cm 2 (mean 11.2 × 7.0 cm 2 in size). The average follow-up was 5.8 months (range: 1–12 months). Among the 36 grafts in our study, all grafts except four showed good to excellent results. The mean graft successful rate is 88%. With our procedure no hematoma formation or shearing force (except one case) occurred in this group of patients during the phase of revascularization, there was, hence, good fixation of the graft by the “tie-over” dressing using elastic rubber bands compared with conventional tie-over dressing, especially in skin grafts of the back site of body and at large graft area. However, it is not suitable for the potentially infectious granulation beds, especially near joint area.

The Micro Trolley Based on SMA and its Control System

The structure and control system of a micro trolley imitating an insect is introduced. Its movement mechanism is analyzed. The micro trolley imitates the motion of creature muscle using an SMA (Shape Memory Alloy) actuator. An elastic rubber band is put side by side with the SMA actuator so that the velocity of movement increases to almost twice as fast as without the elastic rubber band. The anti-reverse device attached to each wheel successfully prevents the wheels from turning backwards. This paper also analyzes the experiment results of the trolley. The prototype can be applied to the inspection and maintenance of micro pipes and tubes in such specific fields as nuclear power plants or space shuttles.

2H NMR Imaging of Strained Elastomers

One of the advantages of NMR imaging is the possibility of using the variety of NMR parameters for contrast formation. In this paper, the quadrupolar interaction of deuterated poly(butadiene) oligomers incorporated into elastic rubber bands was used to generate contrast in2H NMR images of stretched elastomers. The quadrupole splitting of the resonance was exploited to provide a quantitative characterization of the local strain. For this purpose,2H spectroscopic imaging was performed first, which revealed spatially resolved spectra from which the quadrupole splitting was calculated. A similar distinction between isotropic and anisotropic domains within the strained sample could be achieved by application of a double-quantum filter. By this procedure, only the magnetization of the strained areas of the rubber sample was imaged, whereas the magnetization of isotropic regions could be eliminated. With this method, images were obtained in which the contrast is determined by the strength of the quadrupole splitting and the spin density. Furthermore, double-quantum signals from areas could be obtained, where the local strain was too small to be detected as a line splitting with the spectroscopic technique. The spectroscopic method provides quantitative information but is relatively time consuming due to the extra frequency dimension, while the double-quantum-filtered images are obtained much faster and are more sensitive to small anisotropies but do not yield quantitative information unless a set of differently filtered images is evaluated.

Drag reduction by an elastic rubber band?

The influence on the friction behaviour caused by a rubber band held fixed at one end of a circular tube containing a fully developed turbulent flow was investigated. The drag was slightly higher under these conditions with the drag approaching the Prandtl-Karman law at high Reynolds numbers. The results are in contrast to the behaviour of a polymer thread in heterogeneous drag reduction.

A simplified stent dressing technique using elastic rubber bands.

Several techniques of securing dressings over a skin grafted area have been developed. Many of these entail cumbersome and time-consuming procedures. A simple, easy to learn, and very effective method is presented.