Objective: The purpose of this thesis was to determine the degree of difference between anthropometric and heel pad tissue characteristics of the lower extremities of PMHS compared to living populations as well as to establish a wholistic procedure for extensive measurements of the foot using methodology previously used in lower limb anthropometry, x-ray imaging, and ultrasound imaging studies. Methods: Thirty-seven PMHS were included in the anthropometry analysis, 21 PMHS were included in the x-ray analysis, and 32 PMHS were included in the ultrasound analysis. For the anthropometry, measurements were taken in seated and standing positions and included bimalleolar breadth, heel breadth, navicular height (medial prominence), navicular height (inferior medial border), talar head height, plantar curvature height, lateral malleolar height, medial malleolar height, acropodion foot length, hallux foot length, horizontal foot breadth, ball of foot length, and dorsum height. Comparisons were then made between left and right feet, seated and standing positions, males and females, and PMHS and living populations. For the x-ray analysis, two of the anthropometry measurements, navicular height (inferior medial border) and talar head height, had values for anthropometry compared against measurements determined through x-ray imaging. For the ultrasound analysis, ultrasound images were taken of the plantar foot at the calcaneus at loadings of 0, 5, 10, 15, 20, and 30 Newtons. Thicknesses, stiffnesses, and compressibility indexes were determined using the images, and these values were then compared against values seen in living populations. Results: Left and right feet were found to have no significant differences in anthropometry. Seated and standing positions were found to be significantly different in 12 of the 13 measurements. Male values were found to be significantly different from female values in both seated and standing positions for all measurements except for plantar (open full item for complete abstract)

The sympathetic nervous system, a subdivision of the autonomic nervous system, innervates glands, smooth and cardiac muscle of the body and drives the “fight or flight” response. The objective of this study is to use anatomical and radiological methods to definitively identify and investigate the sympathetic chain, specifically ganglia from stellate through T5. The overarching goal of this research is to help guide clinical treatments, including nerve block and ligation procedures, for various disorders of the sympathetic nervous system, including cardiac arrhythmias, hyperhidrosis and pain syndromes. This study uses anatomical methods, including cadaveric dissection, optical tracking, anatomic relationships and landmarks, to investigate the characteristics of the sympathetic chain. This study also uses radiologic methods, including conventional radiography and 3 Tesla (T) magnetic resonance imaging (MRI) with a high-resolution 3D constructive interference in steady state (CISS) sequence, to provide a clinically applicable comparison to gross anatomic observations and measurements.

Automotive crashes are a leading cause of death in the US, with side-impacts being the most fatal. Thoracic injuries are among the leading causes of such fatalities in small, elderly females. Thus, a series of six realistic side-impact post-mortem human surrogate (PMHS) sled tests were conducted. Results showed serious thoracic injuries in all PMHS, despite current side-impact anthropomorphic test devices (ATDs) predicting a <10% probability of such injuries. While this is partially due to the inaccuracy of injury risk scaling, it is hypothesized that combined thoracic loading, anteriorly-posteriorly (A/P) from the seatbelt pretensioner and laterally from the side airbag, increased rib fractures despite less-than-expected lateral chest deflection. The objectives of this study were to investigate the following in small, elderly female PMHS: 1) discrepancies between existing injury risk assessment tools and actual injury outcomes; 2) the effects of seatbelt pretensioners on thoracic injury; and 3) the effect of combined loading from the seatbelt pretensioner and side airbag on thoracic injury in side-impact. Prior to PMHS testing, SID-IIs ATD tests were run to match conditions to the previous study. A foam-padded pneumatic lateral impactor was used as a repeatable airbag surrogate. Three PMHS were tested, each under three different loading conditions: 1) A/P-only (seatbelt pretensioner), 2) lateral-only (airbag surrogate), and 3) combined loading (both). Anterior and posterior aspects of right and left ribs were instrumented with strain gages to detect potential fractures and fracture timing. Chest deflection was measured by axillary- and xiphoid process- level chestbands. Seatbelt load and spine motion were also measured. An anatomical dissection was completed after each test series to document all injuries. Each PMHS first underwent an A/P-only test, resulting in A/P chest compressions of 7-12% and no rib fractures. While the goal was to conduct one (open full item for complete abstract)

Motor vehicle crashes claim thousands of lives each year in the US, and injure millions more. The thorax is the region of the body at greatest risk for serious injury, and thus is of interest for increased protection. In order to improve systems providing occupant protection, a better understanding of the thorax is required, particularly for vulnerable occupants. The work of this dissertation is focused on increasing understanding of the thorax, and does so by examining instrumentation commonly used on the thorax, by introducing a novel analysis technique for understanding thoracic characteristics, and finally by presenting response and injury data for side impact loading. The first study presented here provides an answer to the question, “Do chestbands alter thoracic response to impact?” This was accomplished by conducting a series of repeated impacts on two post-mortem human surrogates (PMHS), at the same impact velocity with 0, 1, and 2 chestbands. This was done for various impact speeds for a total of 22 impacts on the two subjects. `Response' was divided into global response, defined as chest deflection and thoracic stiffness, and local response, defined as the individual rib strain. Results showed no significant difference in global or local response, thus providing support for the commonly held assumption that chestbands do not alter thoracic response to impact. The second study introduces an analysis method, looking at rib strain as a function of chest deflection. An understanding of this relationship is intended to help bridge the gap between existing deflection-based injury criteria and strain-based injury prediction in finite element human body models. To this end, the strain-deflection (S-D) relationship was explored by rib level, fitting five different models to the data and constructing response corridors. It was additionally observed that the S-D relationship, or curve trajectory, tends to remain consistent across impacts on the same subject, (open full item for complete abstract)

Occupational formaldehyde exposure occurs during the embalming and preservation of cadavers as well as other work involving cadavers including moving, dissection, transportation, and cremation. This study examined formaldehyde exposure during the transportation of cadavers and dissected cadavers between medical universities in Ohio and during transportation between an Ohio and a Michigan medical university. Three events were sampled: one employee in one van during event one and two employees in separate vans during event two. Personal replicate samples were collected from the breathing zones of the workers during the cadaver transport. Transportation time included loading and unloading cadavers. A control vehicle was also sampled. Time-weighted average (TWA) exposure to formaldehyde ranged from 0.36 parts per million (ppm) (0.44 mg/m3) to 0.49 ppm (0.60 mg/m3). Eight-hour TWAs were below the Occupational Safety and Health Administration (OSHA) permissible exposure limit of 0.75 ppm (0.92 mg/m3). The eight-hour TWAs were below the OSHA action level of 0.5 ppm (0.62 mg/m3). All eight-hour TWAs exceeded the American Conference of Governmental Industrial Hygienists (ACGIH) ceiling value of 0.3 ppm (0.37 mg/m3). The formaldehyde concentrations by transportation method demonstrated a statistically significant difference between exposures during the cadaver transport, dissected cadaver transport and the control.

Mass properties of the human head are critical elements in developing neck injury threshold criteria in acceleration and impact environments. In order to accurately simulate the dynamics of the head in impact and acceleration environments, valid mass properties data for the human head must exist. The purpose of this study was two-fold: First, to directly measure and generate a useful data set of human head mass properties and anthropometry, and second, compare the results from the direct measurement to measurements obtained using computed tomographic (CT) analyses of the human head. Four cadaveric human heads, all male, were measured. For the direct measurement procedure, each frozen specimen was secured in a lightweight-aluminum box. The mass, center of gravity (CG) and principal moments of inertia (MOI) were then measured. These same properties of the box alone were subtracted from the measured quantities to determine each specimen's mass properties. For the CT analysis, the identical specimen preparation was imaged with CT. With both slice collimation and table feed set at 1 mm, the CT image resolution was 0.284 mm3/voxel. Segmentation of tissue types based on density thresholds was used to divide the volumetric data into brain matter, bone, and fat/skin. Surfaces from these groups were extracted to create volumes representing these structures. Assigning mass densities to the segmented volumes, the mass properties of the head were calculated using MIMICS, a 3D ing program and results were compared. The final results showed the method to be accurate. The average weight for the directly measured heads was 8.96 lb compared to 8.99 lb for the calculated. The average shift in the z-axis (CGz) for the directly measured heads was 0.91 in above the Frankfort origin while the measured shift was 1.00 in on average. Overall, there was no significant difference seen among any of the parameters at α = 0.05.

Kienbock's disease causes degeneration of the lunate bone in the wrist leading to pain and reduced function of the joint. Clinical studies have found a new technique, radial core decompression (RCD) to be clinically effective in improving early stage Kienbock's disease. However, there have been no biomechanical studies characterizing the changes in wrist kinematics following the RCD procedure. The purpose of this study is to determine the changes in lunate and scaphoid motions following the RCD procedure. This study employs an electromagnetic 3-dimensional tracking system, Polhemus 3-SPACE, to measure the motions of the lunate, scaphoid, and third metacarpal in four cadaveric specimens. Specimens were partially dissected and sutures were attached to five major tendons used for wrist motion. Motion sensors were installed on the lunate, scaphoid, and third metacarpal, and a source was installed on the radius. CT scans were taken of the specimens and digitally reconstructed to determine the relationships between bony coordinate systems and sensor coordinate systems. Wrist specimens were installed in a custom test rig and weights were attached to the sutured tendons to simulate muscle tone. The wrists were passively moved through Flexion/Extension and Radial/Ulnar Deviation motion cycles with motion data collected at various positions through the cycles. After collecting motion data for intact wrist specimens, RCD procedures were performed and motion data was collected for the post-RCD wrists. Joint Coordinate Systems were developed for each specimen and test results were calculated as flexion, ulnar deviation, and pronation angles for each position of Flexion/Extension and Radial/Ulnar Deviation motion. Results were normalized so that statistical comparisons could be performed. Results shows statistically signicant differences in wrist motion following the RCD technique. However, most of these differences were less than 4 degrees. This suggests there are minimal clinic (open full item for complete abstract)

It has been shown in side impact automobile accidents that the shoulder is the point of first contact with the intruding door, causing large forces to be carried by the shoulder complex and, upon failure, into the thorax of the occupant. Shoulder kinematics and the distribution of load through the shoulder girdle are well documented for every day functions; however, the response of the shoulder to impact and the transmission of load to the thorax under high-energy impact are not well understood. The mechanical response, or stiffness properties, of the shoulder that would be helpful in future dummy development is also not known. The shoulder response under the oblique loading that occurs when the intruding door does not strike in a purely lateral manner is unknown. The response of the shoulder to impact and the protective relationship between the shoulder girdle and the thorax is critical to understanding human response to lateral impact and to developing countermeasures to prevent and mitigate thoracic, as well as shoulder, trauma. The purpose of this study was to define injury criteria for the shoulder, define the stiffness of the shoulder in response to both lateral and oblique loading, and investigate the protective relationship between the shoulder girdle and the thorax. This study was conducted in two separate phases. Phase I of the research was comprised of 24 lateral shoulder impacts. Phase II included 14 lateral and oblique shoulder impacts. Of the 14 tests, four of them were conducted lateral to the shoulder along the subject's y-axis, four of them were conducted 15° anterior to this axis, and six were conducted 30° anterior to the subject's y-axis. All of the testing utilized a pneumatic ram to impact the shoulders of post-mortem human subjects (PMHSs) at the level of the glenohumeral joint. The first thoracic vertebrae and both shoulders of the subject were instrumented with tri-axial linear accelerometers on the sternum, clavicle, acromion process, and i (open full item for complete abstract)

The Universal Musculoskeletal Simulator (UMS) was developed at the Cleveland Clinic to facilitate general purpose orthopaedic research that allows investigators to study the in vitro forces applied to bones, tendons and ligaments during simulated exercise of cadaver joint systems. In its original state, the UMS hardware consisted of a rotopod (a specialized hexapod robot), a single rotary tendon actuator and custom LabVIEW software for coordinated control and operation of the system. The focus of this work was to 1) enhance the UMS with a multi-tendon actuator system, 2) develop a muscle force optimization algorithm and evaluate it with a static model of the foot/ankle, 3) integrate the algorithm with the UMS software and evaluate it with cadaver specimens, and 4) utilize the enhanced UMS to investigate the individual muscle contributions to center of pressure using cadaver specimens. Completion of the multi-tendon actuator system has enabled researchers to simulate exercise on cadaver joints by using up to five motorized actuators to simulate muscle forces that would occur during exercise while simultaneously contacting the joint with an external load generated by the rotopod. Although the multi-tendon actuator system was first conceived as a necessary enhancement to simulate the key extrinsic muscles of the ankle/foot, required to conduct simulated walking with cadaver feet, it was soon recognized that this system could be utilized to simulate muscles forces of other joints (i.e., shoulder, wrist, spine, etc.) and as such now provides a general purpose test bed for conducting orthopaedic research. Initial cadaver studies of the foot/ankle using the UMS revealed that normal physiological center of pressure patterns were difficult to achieve during simulated walking. Therefore, the primary goal of this effort was to develop an algorithm that would optimize the muscle forces to better achieve the desired medial-lateral and anterior-posterior center of pressure profil (open full item for complete abstract)

Head and spine injuries, such as traumatic brain injury, skull fracture, concussion and osteoligamentous cervical spine injury continue to be prevalent in motor vehicle crashes, athletics and the military. Automotive safety systems, athletic safety equipment and military personal protective paraphernalia designs have generally focused on protection discretely designed on a component basis – head or spine – but not a systems basis, considering the head-spine linkage simultaneously. But since the cervical spine acts as the attachment point for the head, the boundary conditions applied to the cervical spine influence the behavior of the head. Hence, in analyzing injury risk for the head and the spine, each structure composes one portion of an intrinsically linked osteoligamentous system; thus injury risk for the head and the cervical spine might be more appropriately considered concurrently as opposed to individually. Historically, component-based injury protection designs have utilized head and cervical spine injury risk criteria developed from human, animal and anthropomorphic surrogate studies. While a plethora of these prior studies separately analyzed head injury risk via linear acceleration, Head Injury Criterion (HIC) or Gadd Severity Index (GSI), or cervical spine injury risk via axial/shear forces, bending moments or the Neck Injury Criterion (Nij), relatively few of these studies employed a systems-based approach to understand coupled head-cervical spine injury risk behavior. Thus, designing for optimal head and cervical spine injury protection may not be as trivial as separate consideration of head or spine component injury thresholds. Therefore, through a series of six biomechanical engineering studies that comprised the chapters of this dissertation, the work presented here broadly investigated head and cervical spine injury protection on a systems-based approach considering head and cervical spine injury risk simultaneously. In C (open full item for complete abstract)