Headgear use in girls' lacrosse-stakeholders not ready for change.

Purpose: Mandating headgear for field players in girls' lacrosse to reduce head injuries, including concussion, has been heavily debated. However, research regarding the need and effectiveness of mandated headgear use in girls' lacrosse is still developing. Therefore, this qualitative study aimed to identify the need for and barriers to the development of mandated headgear use policies in girls' lacrosse in Ohio. Methods: We conducted six virtual focus groups, three with concussion experts (clinicians and researchers) and three with girls' lacrosse stakeholders (high school players, parents, coaches, and officials). A focus group guide was developed to explore study participants' perceptions and opinions on concussion in girls' lacrosse, headgear use among players, and policies and policy development related to headgear use or a headgear mandate. We developed the codebook using an inductive and iterative approach based on focus group transcripts and used ATLAS.TI to code and analyze the transcript data. Results: Concussion experts and stakeholders understood the potential consequences of concussion but did not perceive concussion as a pervasive problem in girls' lacrosse. The prevention of head and facial injuries was regarded as a potential benefit of headgear use. However, stakeholders expressed that the myriad of arguments discussed opposing mandated headgear use including increased aggressive play and/or targeting, concerns over changes in the game, and cost strongly outweighed the benefits. Finally, both concussion experts and stakeholders identified multiple organizations, including USA Lacrosse, who could act as facilitators and/or barriers to developing, enacting, and implementing headgear policies. Conclusions: Concussion experts and stakeholders identified possible reasons for headgear use related to injury prevention but also identified several important barriers to the development of a headgear mandate for girls' lacrosse in Ohio.

Corrigendum: Maternity care in the Brussels Capital Region: Towards a paradigm shift?

[This corrects the article DOI: 10.18332/ejm/186405.].

Anatomical and Clinical Education in Physical and Occupational Therapy: Influence of Integration and Soft Preservation / Educación Anatómica y Clínica en Terapia Física y Ocupacional: Influencia de la Integración y la Preservación Blanda

SUMMARY: Anatomy and clinical skills are taught separately to physical and occupational therapy students. Formaldehyde is the primary chemical used to embalm donors which creates a challenge in integrating clinical skills into the anatomy curriculum. This study aimed to evaluate the integration of clinical skills into anatomical education using Imperial College London- Soft Preservation (ICL-SP) and formaldehyde embalming through the evaluation of student perceived learning and confidence. Students were invited to complete a survey after dissecting an ICL-SP and formaldehyde embalmed donors and perform clinical tests. It was easier to dissect and identify neurovascular structures on ICL-SP donors compared to formaldehyde. Clinical tests, like measuring range of motion and ligament tests were also more realistic on ICL-SP donors. The integration of clinical skills in the anatomical curriculum increased student perceived understanding of associated anatomy (p < 0.001), gave better understanding of how anatomy is important to their professions (p < 0.001) and increased motivation to learn anatomy (p < 0.001). The integration of clinical skills into anatomical education can facilitate student learning with higher confidence performing clinical skills and is complemented by the utilization of the new ICL-SP methodology instead of the traditional formaldehyde preservation.

Las habilidades anatómicas y clínicas se enseñan por separado a los estudiantes de terapia física y ocupacional. El formaldehído es el químico principal que se usa para embalsamar a los donantes, lo que crea un desafío para integrar las habilidades clínicas en el plan de estudios de anatomía. Este estudio tuvo como objetivo evaluar la integración de habilidades clínicas en la educación anatómica utilizando Imperial College London-Soft Preservation (ICL-SP) y embalsamamiento de formaldehído a través de la evaluación del aprendizaje y la confianza percibidos por los estudiantes. Se invitó a los estudiantes a completar una encuesta después de diseccionar un ICL-SP y donantes embalsamados formolizados y realizar pruebas clínicas. Fue más fácil diseccionar e identificar estructuras neurovasculares en donantes ICL-SP en comparación con los fijados en formaldehído. Las pruebas clínicas, como la medición del rango de movimiento y las pruebas de ligamentos, también fueron más realistas en los donantes de ICL-SP. La integración de habilidades clínicas en el plan de estudios anatómico aumentó la comprensión percibida por los estudiantes de anatomía asociada (p < 0,001), dio una mejor comprensión de cómo la anatomía es importante para sus profesiones (p < 0,001) y aumentó la motivación para aprender anatomía (p < 0,001). La integración de las habilidades clínicas en la educación anatómica puede facilitar el aprendizaje de los estudiantes con mayor confianza en el desempeño de las habilidades clínicas y se complementa con la utilización de la nueva metodología ICL-SP en lugar de la conservación tradicional con formaldehído.

Assessment of pediatric shoulder range of motion and loading response to evaluate the biofidelity of the Large Omni-directional Child (LODC) anthropomorphic test device (ATD) shoulder design.

The shoulder girdle complex, through engagement with the seat belt, influences motor vehicle occupant upper body movement during frontal impacts, affecting the movement of the head and spine. The recently developed Large Omni-directional Child (LODC) anthropomorphic test device (ATD) was designed with flexible shoulder girdle structures that capture the unique kinematics in pediatric occupants. However, the LODC shoulder has not been evaluated for biofidelity due to the lack of biomechanical data available on pediatric shoulder responses. This study evaluated quasi-static pediatric shoulder girdle complex responses through non-invasive displacement measurements. These data were obtained to evaluate, and, if necessary, improve the biofidelity of the LODC ATD. Shoulder range of motion and anthropometric measurements were obtained from 25 pediatric volunteers, ages 8-12 years old. Loads were applied bilaterally exclusively to the shoulder complexes in increments of 25 N up to 150 N per shoulder at 90 and 135 degrees of shoulder flexion. Still photos were used to determine shoulder displacement in the sagittal plane from images captured prior to and following the load applications. Data analysis consisted of motion tracking to evaluate the absolute and relative displacement of the right acromion and T1. The displacements for each volunteer were normalized based on the volunteer's shoulder width compared to the shoulder width of the LODC ATD. For the 90° load, the acromion moved relative to T1 an average of 28.1 mm forward and 3.1 mm downward at maximum displacement. For the 135° load, the acromion moved relative to T1 an average of 15.5 mm forward and 42.7 mm upward at maximum displacement. Similar displacements at higher loads indicated that the volunteers achieved their maximum range of motion. The results of this study will be compared to the LODC ATD, assessing the biofidelity of the shoulder complex.

Comparing dynamic visual acuity between athletes who are deaf or hard-of-hearing and athletes who are hearing.

This study examined the difference in the dynamic visual acuity test (DVAT) between collegiate athletes who are deaf or hard-of-hearing (D/HoH) (n = 38) and university club-level athletes who are hearing (n = 38). Dynamic visual acuity was assessed using the Bertec Vision Advantage (Bertec® Corporation, Columbus, Ohio, USA). No statistically significant differences between athletes who are D/HoH and who are hearing were found in DVAT for leftward (χ2 = 0.71, p = 0.40) or rightward (χ2 = 0.04, p = 0.84) head yaw rotation around an earth vertical axis. Dynamic visual acuity was similar for athletes regardless of hearing status. Baseline DVAT data may be of use for post-injury management of athletes who are D/HoH.

Hearing Status and Static Postural Control of Collegiate Athletes.

CONTEXT: Because of the close proximity of the cochlea, vestibular apparatus, and shared neurovascular structures, the static postural control of athletes who are deaf or hard of hearing (D/HoH) may be different from that of athletes who are hearing. Limited research is available to quantify differences between these athletes. OBJECTIVE: To determine the effect of hearing status and stance condition on the static postural control of athletes. DESIGN: Cross-sectional study. SETTING: Athletic training facilities. PATIENTS OR OTHER PARTICIPANTS: Fifty-five collegiate varsity athletes who were D/HoH (age = 20.62 ± 1.80 years, height = 1.73 ± 0.08 m, mass = 80.34 ± 18.92 kg) and 100 university club athletes who were hearing (age = 20.11 ± 1.59 years, height = 1.76 ± 0.09 m, mass = 77.66 ± 14.37 kg). MAIN OUTCOME MEASURE(S): Participants completed the Modified Clinical Test of Sensory Interaction and Balance on a triaxial force plate. Anteroposterior and mediolateral (ML) center-of-pressure (CoP) velocity, anteroposterior and ML CoP amplitude root mean square, and 95% ellipse sway area were calculated. RESULTS: Athletes who were D/HoH had a larger CoP velocity, larger ML root mean square, and larger sway area than those who were hearing (P values < .01). A significant main effect of stance condition was observed for all postural control variables (P values < .01). CONCLUSIONS: During the Modified Clinical Test of Sensory Interaction and Balance, athletes who were D/HoH demonstrated a larger sway area compared with athletes who were hearing. Therefore, individualized baseline assessments of static postural control may be warranted for athletes who are D/HoH as opposed to comparisons with existing normative data.

Morphology of the Lisfranc Joint Complex.

Lisfranc injuries are complicated injuries of the tarsometatarsal joint with high rates of sequelae. Both anatomy and injury of the Lisfranc joint are variably documented. Descriptions of these injuries and their associated structures vary greatly. The most injured structures are those of the Lisfranc joint complex, which involves the medial cuneiform, second and third metatarsals, and the dorsal, interosseous, and plantar Lisfranc ligaments. This study sought to examine morphology of the Lisfranc joint in cadavers. Twenty-two embalmed cadaveric feet were dissected (13 male, 9 female, 80.3 years ± 14.03) to isolate the bones and ligaments of the Lisfranc joint complex. The dorsal, interosseous, and plantar Lisfranc ligaments were present in each specimen. Each ligament was measured and morphology noted. The dissected dorsal Lisfranc ligament had consistent morphology (mean = 10.8 mm ± 1.79). The interosseous Lisfranc ligament had a consistent path, but 11/17 of specimens possessed a connection to the plantar Lisfranc ligament. The plantar Lisfranc ligament demonstrated wide variability with a Y-variant (n = 3) and a fan-shaped variant (n = 14). Ligament thickness was greatest in the interosseous Lisfranc ligament (mean = 13.74 ± 3.08) and least in the dorsal Lisfranc ligament (mean = 1.36 ± 0.42). While the objective of defining joint and ligament morphology was achieved, further questions were raised. Variations of the interosseous and plantar Lisfranc ligament may play a role in susceptibility to joint injury, and arthritic changes to the joints examined raise questions regarding the prevalence of arthritis in the uninjured Lisfranc joint.

Prevalence and Incidence of Injury during Olympic-style Shooting Events: A Systematic Review.

BACKGROUND: Shooting sports are included in collegiate and Olympic events. However, there is minimal evidence examining injury prevalence and incidence for these athletes. HYPOTHESIS/PURPOSE: The purpose of this study was to systematically review the literature to examine the available evidence regarding the incidence, prevalence, and types of injuries that affect athletes in Olympic-style shooting events. STUDY DESIGN: Systematic review. METHODS: The electronic databases PubMed, Cochrane Library, Cinahl, MEDLINE, and SPORTDiscus were searched utilizing terms related to shooting and injuries. Studies were included if they reported prevalence or incidence of injury in collegiate or Olympic shooting events, and were excluded if inclusion criteria were not met, full text was unavailable, or not in English. Two reviewers independently screened articles in two phases: 1) screening of titles/abstracts 2) full text review. A third reviewer resolved conflicts. RESULTS: Nineteen studies were ultimately included. The sports identified were biathlon, rifle, pistol, and shotgun. Shooting events in both winter and summer Olympics had low percentages of injuries compared to other sports. Winter shooting events had a higher percentage of injuries (6.9%) compared to summer (2.3%). In summer, females demonstrated a higher percentage of injuries (6.9%) compared to males (1.7%). In winter, males had a higher percentage of injuries (8.6%) versus females (5.1%). CONCLUSION: Injury incidence and prevalence was low for athletes in shooting sports in the Olympics. Injury rate was higher in the winter Olympic shooting events likely from increased physiological demand. With injury surveillance focusing on acute injuries rather than chronic, the number of injuries may be underestimated. Females had higher injury rates than males in the summer Olympics while the opposite was observed in the winter Olympics, likely from sex differences and differences in physiological demand for each event. LEVEL OF EVIDENCE: Level 3.

Concussion Epidemiology in Athletes Who Are Deaf or Hard-of-Hearing Compared With Athletes Who Are Hearing.

OBJECTIVE: To compare the epidemiology of concussion between athletes who are deaf or hard-of-hearing (D/HoH) and athletes who are hearing. DESIGN: Descriptive epidemiology study. SETTING: Data were collected from 2 Division III athletic programs. One institution is the world's only university designed to be barrier-free for students who are D/HoH. PARTICIPANTS: Six hundred ninety-three athletes who are D/HoH and 1284 athletes who are hearing were included in this study. Athletes participated in collegiate athletics during the 2012 to 2013 through the 2016 to 2017 academic years. INTERVENTIONS: Concussion data were provided by the athletic training staff at each institution. MAIN OUTCOME MEASURES: Concussion counts, concussion rate, and injury rate ratios (IRRs) with 95% confidence intervals (95% CIs). RESULTS: Thirty athletes who are D/HoH and 104 athletes who are hearing suffered concussions. Athletes who are hearing had an increased injury rate compared with athletes who are D/HoH for all sports combined (IRR = 1.87, 95% CI, 1.26-2.78). Football athletes who are hearing also had an increased injury rate compared with football athletes who are D/HoH (IRR = 3.30, 95% CI, 1.71-6.37). Concussion rate was higher for male athletes who are hearing than male athletes who are D/HoH (IRR = 2.84, 95% CI, 1.62-4.97). No other significant differences regarding concussion risk were identified. CONCLUSIONS: Athletes who are D/HoH in sex-comparable sports may not have a higher rate of concussion than athletes who are hearing. Rate of concussion in football may be greater among athletes who are hearing compared with athletes who are D/HoH.

Isometric, concentric, and eccentric neck strength in the sagittal and coronal planes of motion for adult females.

OBJECTIVE: Assess strength in adult females using multiple positions, motions, and contraction types, to better understand strength production of young and non-symptomatic of adult female subjects to help assess and improve the biofidelity of anthropomorphic test devices and human body models. METHODS: Fifteen adult females (25.4 ± 6.3 years) were recruited for this study. Strength measurements were collected for the sagittal and coronal planes during isometric, concentric, and eccentric muscle contractions in neutral and mid-range of motion anatomical positions. RESULTS: For both planes, subjects were strongest during eccentric muscle contractions and weakest in concentric muscle activations. In the sagittal plane, subjects were stronger in extension for all muscle activation types and anatomical positions. In the coronal plane, there were no side differences in isometric nor concentric strength. CONCLUSIONS: Neck strength of adult females depends on muscle activation type and anatomical positions. Future computational models should account for muscle activation type when quantifying responses of female subjects.

Diet Quality, Carotenoid Status, and Body Composition in NCAA Division I Athletes.

Objectives: In this paper, we examined diet quality and associations between changes in skin carotenoids and body composition among selected NCAA Division I athletes. Methods: Athletes from women's (rowing, swimming, gymnastics) and men's (swimming, wrestling) teams at a large Midwest university (N = 129) completed one online food frequency questionnaire and 2 in-person visits, once in-season and once out-of-season, to assess skin carotenoids and body composition. Diet quality was assessed via Healthy Eating Index-2015 (HEI). Carotenoids were measured via resonance Raman spectroscopy and body composition via dual-energy x-ray absorptiometry. ANOVA and Pearson correlations were used to test differences between teams and determine association between changes from in-season to out-of-season. Results: Mean HEI score for all athletes was 71.0. Women's rowing reported the highest diet quality (73.5), men's wrestling lowest (56.5). Skin carotenoids decreased for all teams, except men's wrestling, from in-season to out-of-season. Body fat percentage increased for women and decreased for men. There was a moderate inverse association between changes in skin carotenoids and body fat percentage (r = -.334, p = .001). Conclusions: Suboptimal diet quality coupled with decreases in skin carotenoids and increases in body fat percentage from in-season to out-of-season may justify dietitian-led interventions year-round to improve dietary patterns in collegiate athletes.

Systematic review of the diagnostic accuracy, reliability, and safety of the sharp-purser test.

Introduction: The Sharp-Purser Test (SPT) is used to assess for atlantoaxial instability (AI) in patients with rheumatoid arthritis (RA). The test is commonly used by clinicians; however, many experts argue it lacks reliability and validity along with concerns of safety. The primary purpose of this review is to determine the diagnostic accuracy of the SPT to detect AI.Methods: A search of five databases was performed from inception to 19 December 2018 using search terms related to the SPT. Studies were eligible for inclusion if the SPT was used on a patient/participant. Methodological quality assessment of diagnostic studies was performed with the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) for studies that reported data to calculate sensitivity (SN), specificity (SP), positive likelihood ratio (+LR), and negative likelihood ratio (-LR).Results: The search yielded 1009 articles, and 32 studies met the inclusion criteria for analysis. Meta-analysis on diagnostic accuracy studies assessing the SPT was not possible due to statistical heterogeneity. Six diagnostic accuracy studies assessed the SN of the SPT ranging from 0.19 to 1.00. Four of the studies assessed SP of the SPT ranging from 0.71 to 0.98. The +LR was identified in 4 studies was 0.655, 1.73, 22, and 17.25. The -LR was 1.14, 0.799, 0.571, and 0.323. Seven RCTs utilized the SPT to screen for AI, and the SPT was used in 18 case reports.Conclusion: The SPT may be inappropriate to use due to inconsistent validity, poor inter-rater reliability, and potential to cause harm.Level of evidence: 1.

Ultrasound as a Diagnostic Tool in the Assessment of Lisfranc Joint Injuries.

OBJECTIVES: Ligamentous Lisfranc injuries are frequently overlooked because of subtle clinical presentations and diagnostic difficulties. The dorsal Lisfranc ligament (DLL) is easily visualized with ultrasound (US), which can provide quick, cost-effective diagnoses of disorders but is not considered standard clinical practice. This study sought to compare DLL measurement accuracy between US and cadaveric dissection. METHODS: Ultrasound images of 22 embalmed cadaveric feet were obtained with an M-Turbo US machine and a 6-13-MHz linear array (FUJIFILM SonoSite, Inc, Bothell, WA). Images were measured in the US unit and again with ImageJ software (National Institutes of Health, Bethesda, MD). Specimens were dissected, and DLL morphologic characteristics were recorded. RESULTS: Twenty-two specimens were scanned, however 4 were excluded, leaving a sample of 11 male and 7 female cadaveric specimens (mean age ± SD, 80.3 ± 14.03 years). The DLL length differences between SonoSite (8.39 ± 1.27 mm) and ImageJ (8.25 ± 1.84 mm) were not significant (P > .05). Both US DLL measurements significantly differed from the gross dissection measurement (10.8 ± 1.85 mm; P < .001). The morphologic characteristics of the DLL at dissection were consistent. Overall, 70% to 80% of the ligament length was represented by US compared to dissection. The dorsal joint space did not differ significantly between SonoSite (2.19 ± 0.49 mm) and ImageJ (2.05 ± 0.52; P > .05). Both US measurements were also significantly larger than dissection measurements (1.04 ± 0.24; P < .001). Intraclass correlation coefficients indicated good reliability for the DLL length (0.835) and moderate reliability for the dorsal joint space (0.714). CONCLUSIONS: The DLL is underrepresented but easily distinguished by US, demonstrating its utility in Lisfranc injury diagnosis. Thus, we propose a 4-component assessment involving US, which may provide more rapid, cost-effective diagnoses of subtle Lisfranc injuries.

Morphological variations and accessory ossicles in the peroneal and tibialis muscles.

This study describes five bilateral anatomical variations in the feet of a 97-year-old male cadaver. Following routine dissection, all variants were measured and documented. Three accessory tendons and two accessory ossicles were identified. Bilateral accessory tendons were present from the tibialis anterior (type II), peroneus tertius (type III), and peroneus brevis muscles. Accessory tendon length was 36-104 mm and width was 1-3 mm each inserting more distally then the main tendon. Accessory ossicles were identified as an accessory navicular and os peroneum, respectively. Individually, each variation has varying prevalence rates in the literature, but to date, no known studies have been published describing the combined presence of all five bilateral variations. The acknowledgement of multi-variant cases such as this one may be helpful in the clinical setting, particularly for patients with pathology or for those undergoing foot and ankle surgery.

Beyond Bones: Assessing Whether Ultrasound-Aided Instruction and Practice Improve Unassisted Soft Tissue Palpation Skills of First-Year Medical Students.

OBJECTIVES: Our purpose was to determine whether ultrasound (US)-aided instruction and practice on musculoskeletal anatomy would improve first-year medical students' ability to locate and identify specific soft tissue structures by unaided palpation in the upper and lower extremities of healthy human models. METHODS: This study was a randomized crossover design with 49 first-year medical students randomly assigned to 1 of 2 groups. Each group was provided expert instruction and hands-on practice using US to scan and study soft tissue structures. During session 1, group A learned the anatomy of the upper extremities, whereas group B learned the lower. Students were then tested on their proficiency in locating 4 soft tissue structures (2 upper and 2 lower extremities) through palpation of a human model. During session 2, group A learned lower extremities, and group B learned upper. At the end of session 2, students repeated the assessment. RESULTS: After the first instructional session, neither group performed significantly better on identifying and locating the soft tissue landmarks they learned aided by US. After the second instructional session, however, scores for both groups increased approximately 20 percentage points, indicating that both groups performed significantly better on palpating and identifying both the upper and lower extremity soft tissue landmarks (Cohen d = 0.89 and 0.82, respectively). CONCLUSIONS: Time and practice viewing soft tissue structures with US assistance seems to have a "palpation-with-eyes" effect that improves students' abilities to correctly locate, palpate, and identify limb-specific soft tissue structures once the US assistance is removed.

Does Ultrasound-Enhanced Instruction of Musculoskeletal Anatomy Improve Physical Examination Skills of First-Year Medical Students?

OBJECTIVES: Ultrasound imaging is commonly used to teach basic anatomy to medical students. The purpose of this study was to determine whether learning musculoskeletal anatomy with ultrasound improved performance on medical students' musculoskeletal physical examination skills. METHODS: Twenty-seven first-year medical students were randomly assigned to 1 of 2 instructional groups: either shoulder or knee. Both groups received a lecture followed by hands-on ultrasound scanning on live human models of the assigned joint. After instruction, students were assessed on their ability to accurately palpate 4 anatomic landmarks: the acromioclavicular joint, the proximal long-head biceps tendon, and the medial and lateral joint lines of the knee. Performance scores were based on both accuracy and time. A total physical examination performance score was derived for each joint. Scores for instructional groups were compared by a 2-way analysis of variance with 1 repeated measure. Significant findings were further analyzed with post hoc tests. RESULTS: All students performed significantly better on the knee examination, irrespective of instructional group (F = 14.9; df = 1.25; P = .001). Moreover, the shoulder instruction group performed significantly better than the knee group on the overall assessment (t = -3.0; df = 25; P < .01). Post hoc analyses revealed that differences in group performance were due to the shoulder group's higher scores on palpation of the biceps tendon (t = -2.8; df = 25; P = .01), a soft tissue landmark. Both groups performed similarly on palpation of all other anatomic structures. CONCLUSIONS: The use of ultrasound appears to provide an educational advantage when learning musculoskeletal physical examination of soft tissue landmarks.

Repeatability testing of a new Hybrid III 6-year-old ATD lower extremity.

OBJECTIVE: Vehicle safety is improving, thus decreasing the number of life-threatening injuries and increasing the need for research in other areas of the body. The current child anthropomorphic test device (ATD) does not have the capabilities or instrumentation to measure many of the potential interactions between the lower extremity and the vehicle interior. A prototype Hybrid III 6-year-old ATD lower extremity (ATD-LE) was developed and contains a tibia load cell and a more biofidelic ankle. The repeatability of the device has not yet been assessed; thus, the objective was to evaluate the repeatability of the ATD-LE. Additionally, a dynamic assessment was conducted to quantify injury threshold values. METHODS: A pneumatic ram impactor was used at 2 velocities to evaluate repeatability. The ATD-LE was fixed to a table and impacted on the plantar aspect of the forefoot. Three repeated trials at 1.3 and 2.3 m/s without shoes and 2.3 m/s with shoes were conducted. The consistency of tibia force (N), bending moment (Nm), ankle range of motion (ROM, °), and stiffness (Nm/°) were quantified. A dynamic assessment using knee bolster airbag (KBA) tests was also conducted. The ATD-LE was positioned to mimic 3 worst-case scenarios: toes touching the mid-dashboard, touching the lower dashboard, and flat on the floor prior to airbag deployment. The impact responses in the femur and tibia were directly collected and compared with published injury threshold values. RESULTS: Ram impact testing indicated primarily excellent repeatability for the variables tested. For all 3 conditions the coefficients of variance (CV) were as follows: tibia force, 1.9-2.7%; tibia moment, 1.0-2.2%; ROM, 1.3-1.4%; ankle stiffness, 4.8-15.6%. The shoe-on condition resulted in a 25% reduction in tibia force and a 56% reduction in tibia bending moment. The KBA tests indicate that the highest injury risk may be when the toes touch the lower dashboard, due to the high bending moments recorded in the tibia at 76.2 Nm, which was above the injury threshold. CONCLUSIONS: The above work has demonstrated that the repeatability of the ATD-LE was excellent for tibia force, bending moment, and ankle ROM. The ATD-LE has the ability to provide new information to engineers and researchers due to its ability to directly evaluate the crash response of the ankle and leg. New information on injury mechanism and injury tolerance may lead to injury reduction and thus help advance the safety of children.

Biofidelity Evaluation of a Prototype Hybrid III 6 Year-Old ATD Lower Extremity.

Incomplete instrumentation and a lack of biofidelity in the extremities of the 6 year-old anthropomorphic test device (ATD) pose challenges when studying regions of the body known to interact with the vehicle interior. This study sought to compare a prototype Hybrid III 6 year-old ATD leg (ATD-LE), with a more biofidelic ankle and tibia load cell, to previously collected child volunteer data and to the current Hybrid III 6 year-old ATD (HIII). Anthropometry, range of motion (ROM), and stiffness measurements were taken, along with a dynamic evaluation of the ATD-LE using knee-bolster airbag (KBA) test scenarios. Anthropometry values were similar in eight of twelve measurements. Total ankle ROM was improved in the ATD-LE with no bumper compared to the HIII. The highest tibia moments and tibia index values were recorded in KBA scenarios when the toes were positioned in contact with the dashboard prior to airbag deployment, forcing the ankle into axial loading and dorsiflexion. While improvements in the biofidelity of the ATD-LE are still necessary, the results of this study are encouraging. Continued advancement of the 6 year-old ATD ankle is necessary to provide a tool to directly study the behavior of the leg during a motor vehicle crash.