Eye Care Service Use and Associated Health-Seeking Behaviors Among Malawian Adults: Secondary Analysis of the Malawi Fifth Integrated Household Survey 2019-2020

Background

The use of eye care services varies among different population groups.

Objective

This study aimed to assess self-reported eye care use (ECU) and associated demographic factors among Malawian adults.

Methods

This study used secondary data from the Malawi Fifth Integrated Household Survey 2019-2020, a nationally representative survey. The study included 12,288 households and 27,336 individuals 15 years and older. We entered age, sex, level of education, residency (urban/rural), and chronic disease into a logistic regression model, and used a confusion matrix to predict the model's accuracy. A P value <.05 was considered statistically significant.

Results

About 60.6% (95% CI 60.0%-61.2%) of those with eye problems accessed formal care 2 weeks before the survey date. A logistic regression model showed that ECU was positively associated with education compared to none (odds ratio [OR] 6.6, 95% CI 5.927-7.366; P<.001), males compared to females (OR 1.2, 95% CI 1.104-1.290; P<.001), and urban residence compared to rural (OR 1.2, 95% CI 1.118-1.375; P<.001). ECU was negatively associated with age (OR 7, 95% CI 6.782-8.476; P<.001) and having chronic diseases (OR 0.6, 95% CI 0.547-0.708; P<.001).

Conclusions

Social support, women empowerment, education, and mobile clinics are key strategic areas that would increase access to eye care in Malawi. Further studies can investigate ECU among the pediatric population.

What differences exist between the lead and trail wrist in extensor carpi ulnaris activity and golf swing joint kinematics in sub-elite golfers?

This study assessed the lead and trail arm peak and average extensor carpi ulnaris (ECU) muscle activity in association with tri-planar angular velocities of the lead and trail wrists during the golf swing. Fifteen sub-elite, male right-handed golfers (Mage = 34.7 years ±13.3, Mhandicap = 1.5 ± 2.2) were recruited to execute five shots each with their pitching wedge, 7-iron and driver clubs in an indoor golf simulator. Surface electromyography (EMG) sensors were placed over the ECU muscle belly and inertial measurement unit sensors were placed bi-laterally on the distal forearm and dorsum of the hand. There was a statistically greater recruitment of the trail ECU muscle during the downswing (p < 0.001) for all clubs. The lead ECU muscle was recruited more during the backswing (p < 0.001) and follow through (p < 0.024) phases. There were statistically different tri-planar movement patterns between the lead and trail wrist throughout all three phases of the golf swing. No significant relationships were found between downswing EMG data and clubhead kinematics at impact. In conclusion, differing wrist kinematics and associated muscle activity may contribute to the asymmetrical injury pattern seen clinically.

A Simplified Modification of the Henderson Extensor Carpi Ulnaris Opposition Transfer

PURPOSE

There are several potential donor muscle-tendon units for a thumb opposition transfer. The extensor carpi ulnaris (ECU) is useful when the more usual donor units are not available. The technique and results of a simplified ECU opposition transfer elongated with a free tendon graft are described.

METHODS

Ten ECU opposition transfers were performed using this modification of Henderson technique in 5 adults after complex trauma, 3 adults with median and ulnar nerve palsies, and 2 children with congenital hand differences.

RESULTS

Seven patients achieved a Kapandji opposition score of 6 to the distal phalanx of the small finger, and 3 patients achieved a Kapandji score of 5 to the distal phalanx of the ring finger. None of the patients required a secondary tenolysis or developed a radial deviation imbalance of their wrist.

CONCLUSIONS

This modification of the Henderson technique using ECU elongated with a free tendon graft and inserted directly and only into the abductor pollicis brevis tendon is an effective method of restoring opposition to the thumb, especially when other conventional donor muscle-tendon units are not available.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Use of Tendon Allograft for Recurrent Extensor Carpi Ulnaris Instability in Ehlers-Danlos Syndrome: A Case Report

Background  Subluxation of the extensor carpi ulnaris (ECU) tendon can be a challenging problem to the surgeon, with no options described for failure following autologous reconstruction. It is our intention to provide guidance on technique by describing our experience in a 20-year-old male with Ehlers-Danlos syndrome. Case Description  The patient presented with pain and snapping of the ECU tendon, and failed both immobilization and ECU reconstruction with autologous extensor retinaculum. A gracilis tendon allograft was used to reconstruct the ECU sheath, in addition to ulnar groove deepening. At 1-year follow-up, the patient had no pain and the ECU was stable without recurrent subluxation. Literature Review  To the authors' knowledge, the use of tendon allograft for stabilization of recurrent ECU subluxation following surgical repair or reconstruction has not been previously described in the medical literature. Clinical Relevance  Utilization of tendon allograft is a viable technique to stabilize the ECU tendon while minimizing the risk in relying on compromised autologous tissue. This report represents the first account of successful reconstruction following failed autologous reconstruction.

(Semi-)Automatically Parsing Private Protocols for In-Vehicle ECU Communications

In-vehicle electronic control unit (ECU) communications generally count on private protocols (defined by the manufacturers) under controller area network (CAN) specifications. Parsing the private protocols for a particular vehicle model would be of great significance in testing the vehicle’s resistance to various attacks, as well as in designing efficient intrusion detection and prevention systems (IDPS) for the vehicle. This paper proposes a suite of methods for parsing ECU private protocols on in-vehicle CAN network. These methods include an algorithm for parsing discrete variables (encoded in a discrete manner, e.g., gear state), an algorithm for parsing continuous variables (encoded in a continuous manner, e.g., vehicle speed), and a parsing method based on upper-layer protocols (e.g., OBD and UDS). Extensive verifications have been performed on five different brands of automobiles (including an electric vehicle) to demonstrate the universality and the correctness of these parsing algorithms. Some parsing tips and experiences are also presented. Our continuous-variables parsing algorithm could run in a semi-automatic manner and the parsing algorithm from upper-layer protocols could execute in a completely automatic manner. One might view the results obtained by our parsing algorithms as an important indicator of penetration testing on in-vehicle CAN network.

Examination of Ulnar-sided Wrist Pain

This article reviews the pertinent history and physical examination maneuvers necessary to arrive at the proper diagnosis of patients with ulnar-sided wrist pain. Surface anatomy is stressed along with provocative maneuvers for maximal efficacy.

A Modified Extensor Carpi Ulnaris Tenodesis with the Sauvé-Kapandji Procedure

Background: Since the Sauvé-Kapandji procedure was introduced in 1936, many modifications were created using dynamic stabilizer, such as the ECU (extensor carpi ulnaris), the FCU (flexor carpi ulnaris), pronator teres to solve proximal ulnar stump pain. We believe that this modification is also another option for distal ulnar stump instability. Methods: From January 1998 to February 2017, there were 13 patients received the Sauvé-Kapandji (S-K) procedure with tenodesis of the ECU to the carpus and interosseous membrane. The average age at operation was 52 years (range, 28 to 63 years). Four had traumatic arthritis (two from distal radial fracture malunion, two had instability of distal radioulnar joint from Essex-Lopresti injury), four had primary osteoarthritis of the distal radio-ulnar joint, two had rheumatoid arthritis, one had gouty arthritis, two had madelung deformity. The average follow-up was 30 months (range, 15 to 72 months). Results: Postoperative pronation/supination of the forearm had significantly improved with the exception of the wrist flexion/extension. After surgery, the mean radioulnar distance was narrowed from 11 mm to 9 mm, but no significant difference in 12 patients. All patients had improved in wrist pain, 10 patients had no pain and 3 patients with mild pain over the distal ulnar stump. The mean grip strength had significantly improved from 51% of the contralateral side to 75%. The lateral and stress X-ray films showed no instability of the distal ulnar stump after surgery. Conclusions: In conclusion, the modified S-K procedure using the tenodesis of ECU provides a multi-directional stability and is a reliable surgical procedure for distal radioulnar disorders.

Dynamics of forearm muscle activity in slanted computer mice use

BACKGROUND

Static muscular activity of muscles activated in the use of the conventional PC mouse is believed to represent a higher risk for the musculoskeletal health of the user than dynamic muscular activity.

OBJECTIVE

This paper presents a compounded muscular activity dynamics indicator (akin to percent relative range), enabling comparison between computer handheld pointing devices.

METHODS

This muscular dynamism approach considers baseline muscular activity (APL, ECR, ECU and ED) relative to the Maximum Voluntary Contraction as well as the dynamics of muscular activation. The latter is computed as the ratio of the difference between APDF90 and APDF10 divided by APDF50 (APDF-Amplitude Probability Distribution Function for the 90th, 50th and 10th percentiles). The paper demonstrates the approach with results of comparative evaluation of a horizontal, a slanted and a vertical PC mouse, through surface EMG monitoring of 20 participants performing standardized graphical task with the devices.

RESULTS

Hand size impacts muscular activity dynamics in these four muscles, which supersedes differences in device geometry, across the range of devices tested.

CONCLUSION

Smaller devices relative to hand size foster more dynamic muscular activity.

A Segmentation Model of ECU Excitation Signal Based on Characteristic Parameters

According to the basic structure and working principle of the excitation signal sensors of a diesel engine electronic control unit (ECU), a segmentation model of an ECU excitation signal based on characteristic parameters (ESCP-SM) is proposed. In the ESCP-SM, the ECU excitation signal is divided into several parts, and each part has its characteristic parameters model. By using the same global parameters and strictly controlling each part’s proportional parameters, the ESCP-SM can achieve signal alignment and dynamic frequency modulation. Based on the simulation experiment, spectrum analysis proves that this modeling method ensures that the original signal’s effective information is not lost. Pearson similarity analysis shows that the similarity between the simulation signal and practical signal reaches 74%, exhibiting strong correlation. In addition, we set up a physical testing environment. ESCP-SM is realized based on virtual instrument technology, and provides excitation signals for a Komatsu 8 ECU. By modifying the parameter configuration, the ECU can drive the injector to work correctly.

Demonstration of a Filterless, Multi-Point, and Temperature-Independent Fiber Bragg Grating Dynamical Demodulator Using Pulse-Width Modulation

We demonstrated in this work a filterless, multi-point and temperature-independent FBG (fiber Bragg grating) dynamical demodulator using pulse-width-modulation (PWM). In this approach, the FBG interrogation system is composed of a tunable laser and a demodulator that is designed to detect the wavelength shift of the FBG sensor without any optical filter making it very suitable to be used in harsh environments. In this work, we applied the proposed method that uses the PWM technique for FBG sensors placed in high pressure and high-temperature environments. The proposed method was characterized in the laboratory using an FBG sensor modulated in a frequency of 6 Hz, with a 1 kHz sweeping frequency in the wavelength range from 1527 to 1534 nm. Also, the method was evaluated in a field test in an engine of a thermoelectric power plant.

Evaluation of CAN Bus Security Challenges

The automobile industry no longer relies on pure mechanical systems; instead, it benefits from many smart features based on advanced embedded electronics. Although the rise in electronics and connectivity has improved comfort, functionality, and safe driving, it has also created new attack surfaces to penetrate the in-vehicle communication network, which was initially designed as a close loop system. For such applications, the Controller Area Network (CAN) is the most-widely used communication protocol, which still suffers from various security issues because of the lack of encryption and authentication. As a result, any malicious/hijacked node can cause catastrophic accidents and financial loss. This paper analyses the CAN bus comprehensively to provide an outlook on security concerns. It also presents the security vulnerabilities of the CAN and a state-of-the-art attack surface with cases of implemented attack scenarios and goes through different solutions that assist in attack prevention, mainly based on an intrusion detection system (IDS).

Low-Cost FPGA-Based Electronic Control Unit for Vehicle Control Systems

The development of new control algorithms in vehicles requires high economic resources, mainly due to the use of generic real-time instrumentation and control systems. In this work, we proposed a low-cost electronic control unit (ECU) that could be used for both development and implementation. The proposed electronic system used a hybrid system on chip (SoC) between a field-programmable gate array (FPGA) and an Advanced RISC (reduced instruction set computer) Machine (ARM) processor that allowed the execution of parallel tasks, fulfilling the real-time requirements that vehicle controls demand. Another feature of the proposed electronic system was the recording of measured data, allowing the performance of the implemented algorithm to be evaluated. All this was achieved by using modular programming that, without the need for a real-time operating system, executed the different tasks to be performed, exploiting the parallelism offered by the FPGA as well as the dual core of the ARM processor. This methodology facilitates the transition between the designing, testing, and implementation stages in the vehicle. In addition, our system is programmed with a single binary file that integrates the code of all processors as well as the hardware description of the FPGA, which speeds up the updating process. In order to validate and demonstrate the performance of the proposed electronic system as a tool for the development and implementation of control algorithms in vehicles, a series of tests was carried out on a test bench. Different traction control system (TCS) algorithms were implemented and the results were compared.

Mid-term outcome (11-90 months) of the extensor retinaculum flap procedure for extensor carpi ulnaris tendon instability

INTRODUCTION

The aim of our study was the assessment of the mid-term outcome of patients treated with a pediculated extensor retinaculum flap for extensor carpi ulnaris (ECU) tendon subluxation including postoperative tendon stability control.

MATERIALS AND METHODS

Twelve patients treated with an extensor retinaculum flap for symptomatic ECU tendon instability were retrospectively evaluated. Follow-up examinations included functional and radiologic assessment. The range of motion, grip strength, DASH score, PRWE score, Krimmer score and subjective satisfaction were recorded. A rotation-movie MRI was conducted before and after surgery to visualize tendon displacement.

RESULTS

Wrist extension was 65.8° (SD 10.0°), flexion 64.2° (SD 12.2°), radial deviation 15.8° (SD 6.0°), ulnar deviation 32.1° (SD 7.2°), pronation 82.5° (SD 9.4°) and supination 85.0° (SD 9.0°). Mean grip strength was 30.5 kg (SD 8.9 kg). Six patients presented an excellent, four a good, one a fair and one a poor result on the Krimmer score. The DASH and PRWE scores showed a mean of 24.2 (SD 25.1) and 32.2 (SD 29.4) points. MRI showed a dislocation (n = 7) or subluxation (n = 5) of the ECU tendon preoperatively. Five patients showed an unchanged displacement pattern postoperatively.

CONCLUSION

The pediculated extensor retinaculum flap as a treatment for a symptomatic ECU instability shows good to excellent results and a high subjective satisfaction independent of postoperative ECU tendon displacement.

Diagnosing extensor carpi ulnaris tendon dislocation with dynamic rotation MRI of the wrist

OBJECTIVE

The purpose of this study was to retrospectively correlate the kinematic dynamic rotation MRI (DR-MRI) of the wrist for assessment of extensor carpi ulnaris (ECU) tendon subluxation and dislocation.

MATERIAL AND METHODS

The presence of an ECU tendon subluxation or dislocation on the DR-MRI report was correlated to findings of the surgical report.

RESULTS

DR-MRI findings showed an ECU subluxation in 12 cases and an ECU dislocation in 13 cases. Surgery showed an ECU subluxation in 13 cases and an ECU dislocation in 12 cases (ĸ = 0.92).

CONCLUSION

DR-MRI is a feasible method to visualize ECU tendon subluxation and dislocation.

Ulnar-sided wrist pain in the athlete (TFCC/DRUJ/ECU)

PURPOSE OF REVIEW

The goal of this manuscript is to review key historic and recent literature regarding extensor carpi ulnaris (ECU), triangular fibrocartilage complex (TFCC) and distal radioulnar joint (DRUJ) injuries, particularly in athletes.

RECENT FINDINGS

Many recent studies examining the ECU focus on clinical and radiographic diagnosis. Several physical exam findings are described in addition to the use of MRI and US. Imaging studies must be clinically correlated due to high incidence of findings in asymptomatic patients. In regard to the TFCC/DRUJ, there are numerous recent studies that support the use of MRA as an adjunctive diagnostic study. There are also a number of repair constructs that are described for the various different kinds of TFCC pathology reviewed here. In summary, there are a number of options for the diagnosis and treatment of ulnar-sided wrist pain. Patient factors, especially in the athletic population, must be taken into account when approaching any patient with these pathologies.

ECU tendon "dislocation" in asymptomatic volunteers

OBJECTIVE

Assess extensor carpi ulnaris (ECU) tendon position in the ulnar groove, determine the frequency of tendon "dislocation" with the forearm prone, neutral, and supine, and determine if an association exists between ulnar groove morphology and tendon position in asymptomatic volunteers.

MATERIALS AND METHODS

Axial proton density-weighted MR was performed through the distal radioulnar joint with the forearm prone, neutral, and supine in 38 asymptomatic wrists. The percentage of the tendon located beyond the ulnar-most border of the ulnar groove was recorded. Ulnar groove depth and length was measured and ECU tendon signal was assessed.

RESULTS

15.8 % of tendons remained within the groove in all forearm positions. In 76.3 %, the tendon translated medially from prone to supine. The tendon "dislocated" in 0, 10.5, and 39.5 % with the forearm prone, neutral and supine, respectively. In 7.9 % prone, 5.3 % neutral, and 10.5 % supine exams, the tendon was 51-99 % beyond the ulnar border of the ulnar groove. Mean ulnar groove depth and length were 1.6 and 7.7 mm, respectively, with an overall trend towards greater degrees of tendon translation in shorter, shallower ulnar grooves.

CONCLUSIONS

The ECU tendon shifts in a medial direction when the forearm is supine; however, tendon "dislocation" has not been previously documented in asymptomatic volunteers. The ECU tendon medially translated or frankly dislocated from the ulnar groove in the majority of our asymptomatic volunteers, particularly when the forearm is supine. Overall greater degrees of tendon translation were observed in shorter and shallower ulnar grooves.

Relative Contribution of the Subsheath to Extensor Carpi Ulnaris Tendon Stability: Implications for Surgical Reconstruction and Rehabilitation

PURPOSE

To identify the varying contributions of the proximal and distal portions of the subsheath of the extensor carpi ulnaris (ECU) to its stability, evaluate the correlation of ulnar groove depth and ECU subluxation, and observe the effect of forearm and wrist positions on ECU stability.

METHODS

Extensor carpi ulnaris tendon position relative to the ulnar groove was measured in 10 human cadaveric specimens with the subsheath intact, partially sectioned (randomized to distal or proximal half), and fully sectioned. Measurements were obtained in 9 positions: forearm supinated, neutral, and pronated and wrist extended, neutral, and flexed. Ulnar groove depth was measured on all specimens.

RESULTS

In 7 of 10 specimens with an intact subsheath, the ECU tendon subluxated out of the groove in at least 1 forearm-wrist position. We noted the subluxation of the ECU tendon in all wrist-forearm positions with the exception of pronation-extension in at least 1 specimen. For partial subsheath sectioning, tendon displacement markedly increased after distal subsheath sectioning but not after proximal sectioning. For full subsheath sectioning, wrist flexion produced subluxation in all forearm positions, and forearm supination produced subluxation in all wrist positions. Maximum displacement occurred in supination-flexion. There was no correlation between ulnar groove depth and ECU subluxation.

CONCLUSIONS

Mild tendon subluxation occurred in the intact specimens in most tested positions. Two positions were remarkable for their consistency in maintaining the tendon within the groove: pronation-neutral and pronation-extension. In fully sectioned specimens, the greatest subluxation occurred in supination-flexion, with supination and flexion independently producing subluxation. Partial sectioning demonstrated that the distal portion of the subsheath played a more important role than the proximal portion in stabilizing the ECU.

CLINICAL RELEVANCE

Subsheath repair or reconstruction should target the distal portion of the subsheath. During postinjury rehabilitation or following surgical reconstruction, combined forearm supination and wrist flexion should be avoided.