Ciaran K. Simms

• Trinity College Dublin

This study analyzed New York Subway incident cases from 2019 to expand on the current understanding of subway train to human collisions. From the 263 incident cases available, 185 (70%) involved train to pedestrian contact. The fatality data were compared with published literature covering 1990 to 2007, showing reasonable agreement in age-, gender-...

Background: Incisional hernias occur after up to 40 per cent of laparotomies. Recent RCTs have demonstrated the role of prophylactic mesh placement in reducing the risk of developing an incisional hernia. An onlay approach is relatively straightforward; however, a variety of techniques have been described for mesh fixation. The biomechanical prope...

Injury assessment during sporting collisions requires estimation of the associated kinematics. While marker-based solutions are widely accepted as providing accurate and reliable measurements, setup times are lengthy and it is not always possible to outfit athletes with restrictive equipment in sporting situations. A new generation of markerless mo...

Computer vision/deep learning-based 3D human pose estimation methods aim to localize human joints from images and videos. Pose representation is normally limited to 3D joint positional/translational degrees of freedom (3DOFs), however, a further three rotational DOFs (6DOFs) are required for many potential biomechanical applications. Positional DOF...

Monocular 3D human pose estimation technologies have the potential to greatly increase the availability of human movement data. The best-performing models for single-image 2D-3D lifting use graph convolutional networks (GCNs) that typically require some manual input to define the relationships between different body joints. We propose a novel trans...

Computer vision/deep learning-based 3D human pose estimation methods aim to localize human joints from images and videos. Pose representation is normally limited to 3D joint positional/translational degrees of freedom (3DOFs), however, a further three rotational DOFs (6DOFs) are required for many potential biomechanical applications. Positional DOF...

Introduction The required fidelity of synthetic materials in surgical simulators to teach tissue handling and repair requirements should be as accurate as possible. There is a poor understanding of the relationship between choice of muscle surrogates and training outcome for trainee surgeons. To address this, the mechanical characteristics of sever...

Simulation is an important adjunct to aid in the acquisition of surgical skills of surgical trainees. The simulators used to enable trainees to learn technical skills, practice skills and to be assessed in competency exams, need to be of the highest standard and to be of consistent design. Input into the design and makeup of task trainers used to t...

Background There are growing concerns about the risk of neurodegenerative diseases associated with heading in football. It is essential to understand the biomechanics of football heading to guide player protection strategies to reduce the severity of the impact. Objective The aim of this study was to assess the effect of football speed, mass and s...

Lower severity cycling collisions, and single cyclist collisions (or single bicycle crashes) are significantly underreported in police statistics, introducing biases into the types of collisions that are available for analysis. Furthermore, many lower severity collisions do not appear in other collision data sources (e.g. hospital and insurance dat...

Summary statement: This review aimed to explore the published evidence with regard to the types and composition of both full- and part-task trainers to teach surgeons extremity exploration procedures in limb trauma management. Studies were included if they reported the development and/or validation of synthetic or virtual task trainers. Studies we...

As both a utility mode of transport and recreational activity, cycling has well-known health, environmental, and economic benefits. For these reasons it has been encouraged in many countries, including the Republic of Ireland. However, with increasing popularity there have been concurrent increases in road traffic related cyclist injuries. This stu...

Pedestrian injuries occur in both the primary vehicle contact and the subsequent ground contact. Currently, no ground contact countermeasures have been implemented and no pedestrian model has been validated for ground contact, though this is needed for developing future ground contact injury countermeasures. In this paper, we assess the predictive...

Pedestrians suffer significant injuries from ground contact, but attempts to reduce them have been limited. A recent study using multi-body simulations showed ground contact injury may be improved by controlling vehicle braking. The aim of the study is to assesses whether controlled braking would be beneficial in real-world collisions. PC-Crash was...

There are growing concerns about the risk of neurodegenerative diseases associated with heading in football. It is essential to understand the biomechanics of football heading to guide player protection strategies to reduce the severity of the impact. The aim of this study was to assess the effect of football speed, mass and stiffness on the forces...

The problem of injury protection for pedestrian is a research hot spot in traffic safety, and simulations are important research tools. In the process of design of simulation experiments, pedestrian gaits become more and more important. Hence in the research three pedestrian gait serials (walking, running and emergency) were found through observing...

Introduction Cycling as a means of transport or recreational activity is increasing in popularity in Ireland. However, increasing numbers of cyclists may lead to an increased number of bicycle collisions and fatalities. The Road Safety Authority is the statutory body for road safety in Ireland but uses police data primarily to collate cycling coll...

The constitutive response of passive skeletal muscle is important for many human body modelling applications, but modelling the tension-compression asymmetry and the anisotropy observed in ex-vivo samples is challenging. Existing microstructural models do not capture the full three-dimensional response while models suitable for application in finit...

Children with cerebral palsy (CP) have been shown to have altered trunk movements during gait resulting in increased loads at the lower lumbar spine. Detailed assessment is possible using 3D gait analysis. However, reliability and quantification of measurement error have not been established. The aim of this study was to evaluate test-retest reliab...

Protecting struck pedestrians during the ground contact phase has been a challenge for decades. Recent studies have shown how ground related injury is influenced by pedestrian kinematics. In this paper we further developed this approach by assessing the potential of controlling vehicle braking to reduce pedestrian ground contact injuries. Applying...

Head injury is one of the most common injury types in vehicle-to-pedestrian collisions, which leads to death and long-term disabilities. However, detailed analysis of pedestrian head injuries in real world collisions is scarce. Thus the current study used two samples of 120 cases and 184 cases extracted from 1060 pedestrian collision cases captured...

This paper arose from exhibitions in Oxford and Dublin and comprises three experiments which look at the relationship between anatomy and art. In the first experiment, a passport photograph, photographic portrait and portrait in oils, all of the same sitter, show how artistic input transforms anatomy from a mere likeness into works of art. In the s...

Rugby union players can be involved in many tackles per game. However, little is known of the regular head loading environment associated with tackling in rugby union. In particular, the magnitude and influencing factors for head kinematics during the tackle are poorly understood. Accordingly, the goal of this study was to measure head motion of a...

Multibody models have not yet been evaluated for reconstructing head kinematics during sports impacts. Accordingly, the goal of this study was to utilise whole-body motion data from twenty upper and mid/lower trunk rugby shoulder tackles recorded in a marker-based 3D motion analysis laboratory to assess the MADYMO human body passive ellipsoid model...

Statement: The role of simulation to teach and access open surgical skills has become more prevalent in recent years. This systematic review synthesizes the totality of evidence with respect to the educational effectiveness of simulators used in open surgical training. A systematic literature search was conducted in PubMed, Embase, CINAHL, Scopus,...

The aim of this study was to use video evidence of tackles in elite level rugby union to identify ball carrier proficiency characteristics, for both lower and upper body tackles, that have a higher propensity to result in Head Injury Assessments(HIA) for the tackler. HIA (n = 74) and non-HIA tackles (n = 233) were categorised as either front-on or...

Objectives: Tackle height laws are an area of controversy in rugby union. It is reported that the tackler is at most risk of a Head Injury Assessment (HIA). Therefore, the aim of this study was to use match video evidence of tackles in elite level rugby union to examine the effect of tackle heights on HIA risk for the tackler. Design: Qualitative...

Background: Suturing techniques for midline abdominal wall incisions vary between surgeons. This study uses a biomechanical abdominal model to assess tissue stretch using different suturing techniques for midline laparotomy closure. Methods: Deformation tests were performed on the linea alba of 48 porcine abdominal walls. Each pattern was tested t...

There is mounting evidence of reduced long-term cognitive ability in rugby players, even in those without a reported history of concussion. The tackle height law is an area of controversy. However, little is known about the effects of repetitive inertial head loading in rugby. Furthermore, the magnitude and influencing factors for head kinematics a...

Due to the physical and high-impact nature of rugby, head impacts can occur within the game which can result in concussion injuries as well as other moderate-to-severe head injuries 1. Concussion has been defined as “a complex pathophysiological process affecting the brain, induced by traumatic biomechanical forces”1 and was found to be one of the...

In rugby union, effective defensive play is highly technical and essential for game outcomes. Therefore, the aim of this study was to identify tackle heights, for given tackle types, that had a greater propensity to result in tackle gainline success for the tackler using match video evidence. The results indicated that tackling the upper legs of th...

Background: Increased loading at the lumbar spine, particularly in the coronal plane, has been reported in children with cerebral palsy (CP). As pelvic and trunk movements associated with Trendelenburg and Duchenne type gait are most significant in the coronal plane, the potential exists for lower lumbar spinal loading to be negatively affected in...

Objective: There is evidence of chronic injury to the head and neck region of Rugby Union players. The aim of this study was to use multibody simulations to examine the effects of tackle height on both Tackler and Ball Carrier head kinematics and neck dynamics. Research Design: Quantitative Exploratory Study Methods and procedures: 45 front-on shou...

Most pedestrians struck by vehicles receive injuries from contact with the vehicle and also from the subsequent ground contact. However, ground related pedestrian injuries have received little focus. This paper uses 1221 German pedestrian collision cases occurring between 2000 and 2015 to assess the distribution and risk factors for pedestrian grou...

Purpose: To use match video evidence of tackles in elite level rugby union in order to identify tackler proficiency characteristics, for both Lower Body and Upper Body Tackles, that result in Head Injury Assessments (HIA) for the tackler. Methods: A review of international rugby union matches (2013-2017) and Pro 12/ERC Champions Cup matches (201...

Background: Given the global nature of schoolbag carriage, there has been extensive research on schoolbag weight and use with resultant guidance on many aspects of carrying a schoolbag. However, there is limited evidence of knowledge translation or parents' awareness of schoolbag carriage. Objective: This study investigated parental awareness of...

Experiments on passive skeletal muscle on different species show a strong asymmetry in the observed tension-compression mechanical behavior. This asymmetry shows that the tension modulus is two orders of magnitude higher than the compression modulus. Until now, traditional analytical constitutive models have been unable to capture that strong asymm...

The tension/compression asymmetry observed in the stress-stretch response of skeletal muscle is not well understood. The collagen network in the extracellular matrix (ECM) almost certainly plays a major role, but the details are unknown. This paper reports qualitatively and quantitatively on skeletal muscle ECM reorganization during applied deforma...

Objectives It has been hypothesised that fatigue may be a major factor in tackle-related injury risk in rugby union and hence more injuries occur in the later stages of a game. The aim of this study is to identify changes in ball carrier or tackler proficiency characteristics, using elite level match video data, as player time-in-game increases. D...

Tackling is a major component of rugby union and effective attacking and defensive play are essential for game outcomes. In this study, a number of pre-contact, contact and post-contact tackle characteristics that had an influence on tackle gainline success for the ball carrier and tackler were identified using match video evidence from European Ru...

ABSTRACT Player-to-player contact inherent in many unhelmeted sports means that head impacts are a frequent occurrence. Model-Based Image-Matching (MBIM) provides a technique for the assessment of three-dimensional linear and rotational motion patterns from multiple camera views of a head impact event, but the accuracy is unknown for this applicati...

There is a substantial prevalence of post-operative incisional hernia for both laparoscopic and laparotomy procedures, but there have been few attempts at quantifying abdominal wound closure methodology in the literature. One method to ascertain a more robust method of wound closure is the identification of the influence of suture placement paramet...

Kinematic analysis of the trunk during cerebral palsy (CP) gait has been well described. In contrast, movement of the lumbar spine is generally ignored. This is most likely due to the complex nature of the spine. As an alternative to using complex sensor protocols, this study modelled the lumbar region as a single segment and investigated character...

Background: The mechanisms of ACL injury in rugby are not well defined. Aim: To describe the mechanisms of ACL injury in male professional rugby players using systematic video analysis. Methods: 36 cases from games played in top professional leagues and international matches were analysed. 5 analysts independently assessed all videos to record...

Detection and visualisation of Collagen structure are important to understand the relationship between mechanical behaviour and microstructure in skeletal muscle since Collagen is the main structural protein in animal connective tissues, and is primarily responsible for their passive load-bearing properties. In the current study, the direct detecti...

The stress–strain behaviour of skeletal muscle is affected by many factors, leading to varied results reported in the literature. This article examines how the physical dimension of samples in in vitro compression tests affects the muscle stress for a given stretch ratio, in both quasi-static and dynamic loading. It is proposed that physically larg...

Primary objectives: To conduct video and statistical analysis on Rugby Union play, focusing mainly on the tackle, to establish the player to player configurations for significant direct head impacts and non-direct head impacts. Research design: Quantitative, observational cohort study. Methods and procedures: Video analysis of 52 significant d...

Model Based Image Matching (MBIM) has potential to assess three-dimensional linear and rotational motion patterns from multiple camera views of head impact events in contact sports. The goal of this study is to assess the accuracy of the MBIM method for estimating 6DOF head kinematics in a vehicle-cadaver impact scenario for which Vicon motion anal...

Excessive trunk motion has been shown to be characteristic of cerebral palsy (CP) gait. However, the associated demands on the lower spine are unknown. This study investigated 3-dimensional reactive forces and moments at the low back in CP children compared to healthy controls. In addition, the impact of functional level of impairment was investiga...

The mechanics of passive skeletal muscle are important in impact biomechanics, surgical simulation, and rehabilitation engineering. Existing data from porcine tissue has shown a significant tension/compression asymmetry, which is not captured by current constitutive modelling approaches using a single set of material parameters, and an adequate exp...

Motivated by the thousands of pedestrians killed each year in train impacts, this paper investigates the life-saving capability of four high-level locomotive bumper concepts. The head motions produced by the four concepts are modeled as one or two square acceleration pulses and are analyzed using the Head Injury Criterion (HIC). Surprisingly, the a...

Roadside safety barriers designs are tested with passenger cars in Europe using standard EN1317 in which the impact angle for normal, high and very high containment level tests is 20°. In comparison to EN1317, the US standard MASH has higher impact angles for cars and pickups (25°) and different vehicle masses. Studies in Europe (RISER) and the US...

Background: There is no global agreement on a schoolbag weight limit and little assessment of its utility. The duration of carriage is another factor yet there is no previous systematic assessment of the utility of cut-off values for it in identifying schoolbag-related discomfort. Objectives: The objectives were to establish if there was a thres...

Objectives: The purpose of this study is to define a computationally efficient Virtual Test System (VTS) to assess the aggressivity of vehicle front-end designs to pedestrians considering the distribution of pedestrian impact configurations for future vehicle front-end optimization. The VTS should represent real world impact configurations in term...

The effect of pedestrian gait on lower limb kinematics and injuries has not been analyzed. The purpose of this paper was therefore to investigate the effect of pedestrian gait on kinematics and injury risk to the lower limbs using the Total Human Model for Safety adult male pedestrian model together with FE models of vehicle front structures. The m...

This paper discusses tension-compression asymmetry properties of Ogden hyperelastic formulations. It is shown that if all negative or all positive Ogden coefficients are used, tension-compression asymmetry occurs the degree of which cannot be separately controlled from the degree of non-linearity. A simple hybrid form is therefore proposed providin...

Schoolbag carriage is a common occurrence and has been associated with musculoskeletal discomfort in children. The current study investigated the relationship between schoolbag-related musculoskeletal discomfort and individual, physical and psychosocial risk factors in primary school children in Ireland. A cross-sectional survey and pretest-posttes...

Pedestrians account for about one third of road accident fatalities worldwide, but there are large regional variations. In general, in highly motorized countries pedestrians account for around 10–20 % of fatalities, but in less motorized countries, pedestrians can account for over 50 % of fatalities. Pedestrians are frequently classed as vulnerable...

Impulse responses of freshly harvested skeletal muscle specimens are presented for the first time using an impact hammer. The mass-tissue assembly represents a single degree of freedom mass-spring-damper system with the mass end free to move. The specimens were extracted from one thigh of a freshly sacrificed pig of approximately three-month old. T...

Incisional Hernia is a severe complication post laparoscopic/laparotomy surgery that is most commonly associated with the linea alba. Although a suture bite width and bite separation of 10mm is used, there has been no quantitative studies that support this suture bite width/separation combination. Similarly, there has been little study on the effec...

Rear impact collisions are mostly low severity, but carry a very high societal cost due to reported symptoms of whiplash and related soft tissue injuries. Given the difficulty in physiological measurement of damage in whiplash patients, there is a significant need to assess rear impact severity on the basis of vehicle damage. This paper presents fu...

Accident data have shown that in pedestrian accidents with high-fronted vehicles (SUVs and vans) the risk of pedestrian head injuries from the contact with the ground is higher than with low-fronted vehicles (passenger cars). However, the reasons for this remain poorly understood. This paper addresses this question using multibody modelling to inve...

During gait analysis, motion of the lumbar region is tracked either by means of a 2-dimensional assessment with markers placed along the spine or a 3-dimensional assessment treating the lumbar region as a rigid segment. The rigid segment assumption is necessary for inverse dynamic calculations further up the kinematic chain. In the absence of a ref...

Most surgical innovations require extensive preclinical testing before employment in the operative environment. There is currently no way to develop and test innovations for abdominal wall surgery that is cheap, repeatable and easy to use. In hernia repair, the required mesh overlap relative to defect size is not established. The aims of this study...

This paper evaluates the potential of gabions as roadside safety barriers. Gabions have the capacity to blend into natural landscape, suggesting that they could be used as a safety barrier for low-volume road in scenic environments. In fact, gabions have already been used for this purpose in Nepal, but the impact response was not evaluated. This pa...

Regression equations based on pelvic anatomy are routinely used to estimate the hip joint centre during gait analysis. While the associated errors have been well documented, the clinical significance of these errors has not been reported. This study investigated the clinical agreement of three commonly used regression equation sets (Bell et al., Da...

Incisional hernia is a severe complication post-laparoscopic/laparotomy surgery that is commonly associated with the linea alba. However, the few studies on the mechanical properties of the linea alba in the literature appear contradictory, possible due to challenges with the physical dimensions of samples and variations in protocol. This study...

Mechanical swivel seat adaptations are a key aftermarket disability modification to any small- to medium-sized passenger vehicle. However, the crashworthiness of these devices is currently unregulated and the existing 20g dynamic sled testing approach is prohibitively expensive for prototype assessment purposes. In this paper, an alternative quasi-...

In this paper the tracking system used to perform a scaled vehicle-barrier crash test is reported. The scaled crash test was performed as part of a wider project aimed at designing a new safety barrier making use of natural building materials. The scaled crash test was designed and performed as a proof of concept of the new mass-based safety barrie...

The trunk has been shown to work as an active segment rather than a passenger unit during gait and it is felt that trunk kinematics should be given more consideration during gait assessment. While 3-dimensional assessment of the thorax with respect to the pelvis and laboratory can provide a comprehensive description of trunk movement, the majority...