Download List of Submitted Abstracts - College of Engineering and Computer

List of Submitted Abstracts
Safety Study of Intravenously Administered Human Cord Blood Stem Cells in the
Treatment of Symptoms Related to Chronic Inflammation
Brian M. Mehling1, Louis Quartararo1, Marine Manvelyan1, Paul Wang1, Dong-Cheng Wu2, 3
1
Blue Horizon International, LLC, 214 State Street, Hackensack, New Jersey 07601, USA;
2
Biochemistry Institute, Wuhan University, Hubei 430071, P.R. China;
3
Department of Stem Cells, Wuhan Hongqiao Brain Hospital, Wuhan, Hubei 430071, P.R. China
Keyword: chronic inflammatory diseases, umbilical cord blood derived mesenchymal stem cells (UCMSCs), intravenous infusion
Stem cell research plays an important role in orthopedic regenerative medicine today. Arthritis literally
means "inflammation of a joint." Mesenchymal Stem Cells (MSCs) represent a valuable tool for therapy
of symptoms related to chronic inflammatory diseases. Blue Horizon Stem Cell Therapy Program is a
leading provider of adult and children’s stem cell therapies. The purpose of this study is primarily to
monitor the immune response in order to validate the safety of intravenous infusion of human umbilical
cord blood derived MSCs (UC-MSCs), and secondly, to evaluate effects on biomarkers associated with
chronic inflammation. Our study of blood test markers of 9 patients with chronic inflammation before and
within three months after MSCs treatment demonstrates that there is no significant changes and MSCs
treatment was safe for the patients. Analysis of different indicators of chronic inflammation included in
initial, 24-hours, two weeks and three months protocols showed that stem cell treatment was safe for the
patients. Further close monitoring and inclusion of more patients are necessary to fully characterize the
advantages of UC-MSCs application in treatment of symptoms related to chronic inflammation.
Microbiological Analysis of a Failed Periprosthetic Knee Demonstrates Biofilms on
Multiple Components Including Permanent Sutures
- Matthew Swearingen, Ph.D.
Bacterial biofilms are a major etiological agent of periprosthetic joint infection (PJI). However, it
is unclear if biofilms colonize one or multiple components of an artificial joint. Here, we map
biofilm colonization on explanted orthopedic hardware from a revision total knee PJI. Because
biofilms are capable of colonizing a variety of surfaces, we hypothesized that the biofilm would
be associated with all components. To test this hypothesis, we used a novel agar encasement
culturing method (AECM), confocal microscopy (CM), and 16s rRNA gene metagenomic
analysis to analyze biofilm location and community composition on explanted cobalt-chromium
(Co-Cr), titanium, plastic, and suture materials. The AECM allowed for visualization of biofilm
outgrowth on the surface of the Co-Cr femoral component and suture material, and CM
confirmed the presence of staphylococci and putative bacterial rods in biofilms on the sutures. A
metagenomic analysis of the individual components revealed a richness of Bacteroides,
Pseudomonas, Stenotrophomonas, Staphylococcus, Acinetobacter and Proprionibacterium
species on the explanted components confirming that this was a polymicrobial infection despite
clinical culture only recovering Bacteroides at the same time point. Lastly, these data provide
further support that all components, including permanent sutures, should be considered for
explantation in cases of PJI.
Spinal Fusion Fixation Device Test Protocol and Analysis
- Larson, Piasecki, Suhr, Weiss
This study was conducted in order to design, construct, and validate test block models according
to ASTM Standard F1717 for three existing spinal fusion devices from X-Spine Systems, Inc., in
collaboration with X-Spine President and CEO Dr. David Kirschman, M.D. and X-Spine Vice
President of Engineering Mr. Eric Linder. The ​three devices that were studied
include the Fortex Pedicle Screw System, the Fixcet Spinal Facet Screw System, and the Axle
Interspinous Fusion System. All possible variations of the three devices were designed and
validated through finite element analysis (FEA) in SolidWorks. In order to properly evaluate the
stability of each model, they were subjected to compression, torsion, and fatigue testing. The test
block models were then assembled and physically tested in order to validate results. The results
confirmed the optimal variation that will most effectively permit spinal fusion in the lower
lumbar region.
Improvement of a finite element model of a lumbar spinal segment through calibration
techniques
- A. Piasecki, S. Suhr, C.Weiss
A computational biomechanical study was performed on a functional spinal unit of the L4-L5
vertebral segment. The 3D spinal units were constructed from patient specific magnetic
resonance imaging (MRI) files using Mimics (Materialise, Inc). The images were then meshed
by Mimics and imported into ABAQUS for computational analysis. The calibration method
consisted of using in vitro range of motion data in order to provide a stepwise addition of
components. Each addition of an anatomical component required modifications in order to match
the in vitro data before a new component could be added. The FSU were converged when results
obtained were with +/- 5%. This presentation provides these details for 3 models that were
converged and tested simulating the activities of daily living.
Quantification of Residual Limb Skin Health and Circulation in Response to Elevated
Vacuum Suspension
- Matthew Wernke
Management of Skin Temperature and Perspiration Using a SmartTemp Prosthetic
Liner
- Matthew Wernke
Elevated skin temperatures and excessive perspiration inside a prosthetic socket and liner
system are a major complaint among amputee prosthetic users leading to a reduced quality of
life. Prosthetic socket systems encapsulate the residual limb within materials that are
insulators. Previous work by Klute and Webber documented the thermal conductivity of
common socket and interface materials. Both studies confirm that these materials are poor
conductors of heat. A recent advancement in prosthetic liner technology, the SmartTemp
liner, sought to address this significant issue by incorporating a proprietary phase-change
material to store thermal energy. The purpose of this work was to evaluate the performance
of the SmartTemp liner in a double-blind randomized clinical trial. Eight transtibial amputees
participated in the study. Temperature was measured at 4 locations on the residual limb and
the amount of perspiration was measured by wiping the leg and inner liner surface. The
results indicate that the SmartTemp liner significantly reduced the increase in temperature
over the activity period as well as the amount of perspiration.
Anodized TiO2 Nanotube Film for Controllable Drug Delivery
- Lei Kerr and Huiying Jia
TiO2 nanotubes have great potential to improve the performance of Ti implants as a
surface coating due to their high surface area, ability to promote bone growth and
biocompatibility. However, there are two issues need to be solved before further
advancing TiO2 nanotubes technology as drug carrier: uncontrolled drug release and poor
mechanical properties. In this study, a drug carrier using composite of biodegradable
polymer/TiO2 nanotubes is engineered. Carprofen and lidocaine were selected as test
drugs. A simple characterization method is developed to investigate the infiltration of
polymer into TiO2 nanotubes. The synthesized drug carrier demonstrated much better
sustained drug release profile, greatly improved mechanical strength and flexibility
compared to pure TiO2 nanotubes coating. It has also been found that the drug release
kinetics using the synthesized drug carrier is controlled mainly by the drug solubility,
polymer degradation and electrostatic force between drug and polymer, which are pH
dependent.
Failure Investigation of a Tibiotalocalcaneal Arthrodesis System
- Dinesh Gundapaneni
An intramedullary (IM) nail is inserted in the ankle to fuse the joints and to reduce pain
from various conditions such as arthritis and trauma. Nailing is used in a variety of other
situations to treat fractures particularly of long bones. This paper is a case study of
prematurely failed device which describes the failure analysis of an ankle intramedullary
nailing system implanted in a 49 year old male patient. The failure location was proximal
of the two distal interlocking screw holes laterally. Optical and scanning electron
microscopes were used to identify the fracture origin and energy dispersive X-ray
analysis was performed on the nail system components to check material conformity.
Finite element analysis (FEA) was performed to determine maximum Von Mises stresses
during torsion and axial load to failure of the implant was determined by conducting
statistical analysis. The implant failed due to multiple factors involving clinical and
biomechanical reasons. Lack of proper bone purchase while inserting the screw, forces
and torsion developed during the gait exceeded the stiffness range of the implant
resulting in earlier failure.
A three dimensional finite element model of Anterior Cruciate Ligament under
elastic, viscoelastic and hyperelastic conditions
- Bharadwaj Cheruvu
The purpose of this study is to determine the effect of three most common techniques
utilized to model knee ligaments on joint kinematics under loading conditions found
during gait. It is hypothesized that the ligaments modeled as hyperelastic would result in
more realistic kinematics. Two models of the knee were developed using CT and MRI
from healthy, young male and female. FE models were generated with ACL represented
as two 3D bundles. The FE model used to simulate four functional loading conditions.
ACL modeled as elastic structure had highest Von mises stress for all of the loading
conditions. Females with hyperelastic modeling had higher Von mises stress than males
with same modeling structure. Regardless of the modeling technique, the location of the
maximal stress was found at femoral attachment on the ACL, where it wraps around the
bone when load is applied. Findings from this study elucidates some understanding on
why there is an increased risk of ACL injury among women.
Electrochemical Analysis of of Fretting Corrosion at Taper-Trunnion Interface
- Harrison Martin
One of the most prevalent issues regarding Metal on Metal (MOM) hip implants is
fretting corrosion, a result of cyclic motion between the taper (female component) and the
trunnion (male component). The metal ions that are released as a result of fretting
corrosion can potentially have adverse effects on the surrounding tissue within the hip,
leading to pain and premature replacement. The predominant methods for measuring
fretting corrosion have been primarily qualitative; however, a quantitative method for
measurement is possible through electrochemical analysis. This is a short-term test that is
meant to provide quantitative results allowing different designs to be compared with
regards to fretting corrosion generated. When the oxidation layer of a metal object is
breached the half-cell potential of the object is changed, which produces a voltage
difference. We can use this voltage difference as a way to quantify fretting-corrosion
typically through a current measurement. We have conducted experiments in which this
process has been mimicked, and the results for multiple materials and time durations have
been produced. Based on the results of these experiments, we think electrochemical
analysis is an accurate and efficient method for comparing fretting corrosion amounts
between different taper-trunnion design configurations.
Design of TKR Tibial Insert for Bowlegged Gait
- J. Hutchison, M. Gardner D.
FEA Analysis of the Taper-Trunnion Interface in a Metal on Metal Hip Implant
- Kyle Bradley
Metal on metal total hip replacements are a common procedure in which the hip joint is
replaced with a metal stem, a metal femoral head and a metal socket, usually made of
titanium or cobalt chromium. The stem has a tapered region (trunnion) where the
femoral head is impacted onto. This creates what is known as the taper-trunnion
interface within a hip implant. However, these hip implants seem to be very susceptible
to fretting corrosion, where the corrosive fluid environment of the body accelerates the
process of wear between two contact surfaces. Previous research has suggested that the
design parameters of the taper and the trunnion could have a significant effect on the
amount of fretting corrosion that is occurring at this interface. The parameter that
showed the most promise is angular mismatch, or the difference in angles between the
taper and the trunnion. Utilizing finite element analysis, we tested five different degrees
of angular mismatch using a simplified model of the interface. We then recorded the
maximum contact stresses along with the measured micro-motion of the trunnion against
the taper. Finally we report and compare the difference in fretting work done between
the different angular mismatched specimens.
Surface Roughness Variation with Surface Finish on Trunnion-Taper Interface
- Amber L. Lee
The trunnion-taper interface of a hip implant is known to undergo fretting corrosion,
which can lead to many issues in the body including metal toxicity. Manufacturing
parameters such as surface roughness could be a factor in fretting corrosion, as larger
asperities in the surface could cause more fretting corrosion. Polishing, turning, and
grinding each produce different surface roughnesses. A white light interferometric
microscope is an effective way to measure surface roughness. It provides a close up look
at surface topography and a better understanding of the roughness parameters. The
overall goal of this research is to find a relationship between fretting corrosion and
surface roughness. To do this, we needed to control our manufacturing process for
surface roughness. We chose to machine all of our trunnion coupons by turning them on
the lathe. We were able to alter the depth and width of the asperities in the surface by
changing machine settings. This allowed us to produce specimens with an acceptable
range of arithmetic mean roughness values that were within manufacturing tolerances of
commercially available trunnions. Our results provide a correlation of machine and
surface roughness parameters that will be used in subsequent experiments.
Future of Bearing Materials in Orthopaedics
-
Venkat Narayan
Antioxidant-stabilized ultra-high molecular weight polyethylene (UHMWPE) materials
build upon the learning from the evolution in polyethylene materials so far. Oxidation of
polyethylene has been shown to be the single most critical cause of failure of polymeric
bearings. The failure stems from the generation of free radicals within the polyethylene
material due to exposure to ionizing radiation that was effected to sterilize the device or
to crosslink the polyethylene bearing or both. Previous UHMWPE materials, which have
incorporated a high degree of crosslinking using high energy ionizing radiation such as
gamma or e-beam, have been stabilized by thermal means with varying success. The
stabilization by incorporation of an antioxidant is somewhat recent phenomenon in
orthopaedics. While the benefits to patients with emerging changes to demographics is
apparent, concerns with the biological risks due to the additive has been a largely
inhibiting influence. The incorporation and characterization of a hindered phenol
antioxidant, tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], PBHP, into GUR
1020 UHMWPE that was compression molded and irradiated, to yield an antioxidantstabilized UHMWPE, AOX, is described here that addresses these concerns effectively.
A review of gene expression patterns in the ruptured anterior cruciate ligament
- Landon Polakof
The incidence of anterior cruciate ligament (ACL) injuries has increased over past
decades in parallel with participation in sports, with females at increased risk compared
to males when participating in similar activities. The etiology of this increased risk is
believed to be multifactorial, including anatomical and hormonal differences as well as
variation in muscle recruitment and movement patterns. A recent area of research has
focused on gene expression patterns in ACL injury which might explain these differences
seen in both risk and injury that are observed on an epidemiological level. This review
attempts to encompass current literature on gene expression in the intact and ruptured
ACL, as well as variations that occur based on sex and age. The intact ACL is
transcriptionally unique, and following injury, rapid changes in gene expression occur,
with catabolic inflammatory cytokines peaking early before anabolic markers appear 9
days post-injury. Males and females have differentially expressed major markers of
healing, including ACAN, FMOD, and WSP1. Younger patients show increased levels of
catabolic genes, including ADAMTS4, ADAMTS5, MMP1, and MMP13. Further
elucidation of these differences in gene expression may have great impact in tailoring
ACL injury prevention and treatment strategies to at-risk individuals.