Clinical trial of a low-cost external fixator for global surgery use.

PURPOSE: A low-cost modular external fixator for the lower limb has been developed for global surgery use. The purpose of this study is to assess outcome measures in the first clinical use of the device. METHODS: A prospective cohort study was conducted with patients recruited in two trauma hospitals. Initial clinical procedure data were collected, and patients were followed up every two weeks until 12 weeks or definitive fixation. Follow-up assessed infection, stability, and radiographic outcomes. In addition, patient-reported outcomes and surgeons' feedback on device usability were collected by questionnaires. RESULTS: The external fixator was used on 17 patients. Ten were mono-lateral, five were joint spanning, and two were delta configuration. One patient had a pin site infection at 12-week follow-up. All were stable when tested mechanically and using radiographic assessment, and 53% were converted to definitive fixation. CONCLUSION: The low-cost external fixator developed is appropriate for use in global surgery trauma centres with good clinical outcomes. PROSPECTIVE TRIAL REGISTRATION NUMBER AND DATE: SLCTR/2021/025 (06 Sep 2021).

Use of external fixators in developing countries: a short socioeconomic analysis.

The use of external fixators (EFs) dates back to 377 BC Hippocrates' time, and it has a wide range of orthopaedic applications. External fixator has expanded its use in the management of fractures and other musculoskeletal conditions. It is widely used all over the world to manage complex musculoskeletal injuries. It has many advantages as compared to internal fixation in some trauma scenarios. However, the cost of the external fixators presents a dilemma to the healthcare system in developing countries. The goals of this review article are to explain the importance of EFs in developing countries in managing fractures, to determine the problems encountered at present during external fixation by developing countries, to identify solutions that could be used to address these issues, expand the use of external fixation into other domains of treatment, the impact of COVID-19 pandemic on fracture management based on existing literature. In conclusion, EFs are very expensive, researches have been conducted to overcome these barriers in developing countries. However, there are limitations in implementing in developing countries. It is important to have affordable and clinically acceptable EFs available in developing countries.

Obtaining patient torso geometry for the design of scoliosis braces. A study of the accuracy and repeatability of handheld 3D scanners.

OBJECTIVE: Obtaining patient geometry is crucial in scoliosis brace design for patients with adolescent idiopathic scoliosis. Advances in 3D scanning technologies provide the opportunity to obtain patient geometries quickly with fewer resources during the design process compared with the plaster-cast method. This study assesses the accuracy and repeatability of such technologies for this application. METHODS: The accuracy and repeatability of three different handheld scanners and phone-photogrammetry was assessed using different mesh generation software. Twenty-four scans of a single subject's torso were analyzed for accuracy and repeatability based on anatomical landmark distances and surface deviation maps. RESULTS: Mark II and Structure ST01 scanners showed maximum mean surface deviations of 1.74 ± 3.63 mm and 1.64 ± 3.06 mm, respectively. Deviations were lower for the Peel 1 scanner (maximum of -0.35 ± 2.8 mm) but higher with the use of phone-photogrammetry (maximum of -5.1 ± 4.8 mm). The mean absolute errors of anatomical landmark distance measurements from torso meshes obtained with the Peel 1, Mark II, and ST01 scanners were all within 9.3 mm (3.6%), whereas phone-photogrammetry errors were as high as 18 mm (7%). CONCLUSIONS: Low-cost Mark II and ST01 scanners are recommended for obtaining torso geometries because of their accuracy and repeatability. Subject's breathing/movement affects the resultant geometry around the abdominal and anterolateral regions.

An engineering review of external fixators.

External Fixators are a common technique used to treat a variety of issues related to bones, predominantly due to its non-intrusive nature and versatility in terms of form and materials. While it is mainly used to treat open fractures, its other uses include limb lengthening, deformity correction, bone grafting, compression of non-unions and stabilization of dislocations. Its earliest use dates as far back as 400 BCE and has undergone significant improvements, focusing on both customization and optimization. These two aspects highlight the significance of complementing the orthopaedic requirements with engineering knowledge and its applications. Hence, this review paper aims to conduct an examination of recent developments of external fixators with a special focus on its structure, the usage of materials and biomechanical investigations using experimental and numerical techniques. The paper presents the existing level of engineering knowledge with regards to these aspects and identifies research gaps, which can improve the quality of the commonly used external fixators.

Mechanical Properties of Double Network Poly (Acrylic Acid) Based Hydrogels for Potential Use as a Biomaterial.

Load-bearing applications of hydrogels include soft robots, tissue engineering, and stretchable electronics. This paper presents an extensive study of double network poly (acrylic acid) based hydrogel on stress relaxation, compression fatigue, shear stress, and shock absorption properties as a potential load-bearing soft tissue replacement biomaterial. Double network poly (acrylic acid) hydrogel was selected due to simple processing and availability. The optimized formulation of poly (acrylic acid) hydrogel was used for samples preparation. The compression modulus varied with hydrogel formulation, crosshead speed and swelled amount of the hydrogel. Stress relaxation and shock absorption properties of hydrogel were compared with polyurethane gel used in soft insoles (Shore 5A). Developed hydrogel displayed good fatigue properties up to 10,000 loading cycle at maximum stress of 390±30 kPa and at 84±4% strain. Further, maximum average shear stress and shear modulus of 80 kPa and 140 kPa respectively were observed at 84% strain before fracture.

A Wearable System to Analyze the Human Arm for Predicting Injuries Due to Throwing.

There is limited understanding on factors that contribute to throwing related injuries that frequently occur in sports such as Baseball, Cricket and Javelin throwing.This preliminary study focuses on the development of a real time wearable system focusing on extracting key parameters related to potential upper arm injuries associated with the throwing action in the game of Cricket. A wearable system is developed to analyze Electromyography (EMG) signals for detecting muscle activity and Inertial Measurement Unit (IMU) data for monitoring the arm motion.The extracted parameters are then used for analysis, focusing on detecting established indicators of potential injuries. Additionally, an unsupervised learning algorithm is developed towards identifying novel relationships indicating potential injuries.

The levels of plasma low density lipoprotein are independent of cholesterol ester transfer protein in fish-oil fed F1B hamsters.

BACKGROUND: Cholesterol ester transfer protein (CETP) plays a major role in regulating the levels of LDL- and HDL-cholesterol. We previously observed a fish-oil-induced elevation of low-density lipoprotein (LDL)-and very-low-density lipoprotein (VLDL)-cholesterol concentrations and a decrease in high-density lipoprotein (HDL)-cholesterol concentration in F1B hamsters. The molecular mechanism/s by which fish oil induces hyperlipidaemic effect was investigated in this study. We examined whether the effects of dietary fish oil on plasma lipoprotein concentrations are due to fish-oil-induced alterations in plasma CETP activity. MIX diet, a diet supplemented with a mixture of lard and safflower oil, was used as the control diet. RESULTS: We found that fish oil feeding in hamsters reduced CETP mass as well as CETP activity. Increasing the dietary fat level of fish-oil from 5% to 20% (w/w) led to a further decrease in CETP mass. Supplementation with dietary cholesterol increased both CETP mass and CETP activity in fish-oil and MIX-diet fed hamsters. However, there was no correlation between CETP mass as well as CETP activity and LDL-cholesterol concentrations. CONCLUSION: These findings suggest that cholesterol ester transfer between HDL and LDL is not likely to play a major role in determining fish-oil-induced changes in LDL- and HDL-cholesterol concentrations in F1B hamsters. A possible role of reduced clearance of LDL-particles as well as dietary fat level and dietary cholesterol dependent changes in LDL-lipid composition have been discussed.

A diffusion and T2 relaxation MRI study of the ovine lumbar intervertebral disc under compression in vitro.

The ovine lumbar intervertebral disc is a useful model for the human lumbar disc. We present preliminary estimates of diffusion coefficients and T2 relaxation times in a pilot MRI study of the ovine lumbar intervertebral disc during uniaxial compression in vitro, and identify factors that hamper the ability to accurately monitor the temporal evolution of the effective diffusion tensor at high spatial resolution.

Hyperlipidaemic effect of fish oil in Bio F1B hamsters.

We investigated the dietary influence of low and high levels of fish oil, supplemented with or without dietary cholesterol, on the plasma lipoprotein profile in Bio F1B hamsters, a model susceptible to diet-induced hyperlipidaemia. The MIX diet, a diet supplemented with a mixture of lard and safflower-seed oil, was used as the control diet to maintain the saturated MUFA and PUFA levels similar to the fish-oil diet. The animals were fed the specific diets for 2 weeks and fasted for 14 h before killing. The plasma from the animals fed high levels of fish oil was milky and rich in chylomicron-like particles. The plasma total cholesterol, VLDL- and LDL-cholesterol and -triacylglycerol concentrations were significantly higher, whereas HDL-cholesterol was lower in hamsters fed fish oil compared with the MIX-diet-fed hamsters. Increasing the amount of fat in the diet increased plasma lipids in both the fish-oil- and the MIX-diet-fed hamsters; however, this hyperlipidaemic effect of dietary fat level was greater in the hamsters fed the fish-oil diet. The hepatic lipid concentrations were not dramatically different between the fish-oil-fed and the MIX-diet-fed hamsters. However, the hepatic LDL-receptor mRNA levels were significantly low in the fish-oil-fed hamsters compared with the MIX-diet-fed hamsters. Increasing the amount of fish oil in the diet further decreased the hepatic LDL-receptor mRNA expression. It is concluded that F1B hamsters are susceptible to fish-oil-induced hyperlipidaemia, especially at high fat levels, and this increase is partially explained by the inhibition of hepatic LDL-receptor mRNA expression.