Browse Topic: Knee

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Active Implants Receives FDA Breakthrough Device Designation for NUsurface Meniscus ImplantTBMG-357671/1/2020
FDA has granted a Breakthrough Device Designation to Active Implants’ NUsurface® Meniscus Implant. Active Implants, LLC develops orthopedic implant solutions for joint preservation. The NUsurface Meniscus Implant is the first “artificial meniscus” to be marketed in Europe and, if cleared by the FDA, would be the first artificial meniscus in the United States.
Harvesting Energy from the Human KneeTBMG-350979/1/2019
An energy harvester attached to the wearer’s knee can generate 1.6 μW of power while the wearer walks without any increase in effort. The energy is enough to power small electronics like health monitoring equipment.
Surgeons Use Augmented Reality to Reconnect Blood VesselsTBMG-349258/1/2019
Following severe trauma, patients may have tissue damage or open wounds that require reconstructive surgery using fasciocutaneous flaps. These flaps of tissue, which are taken from elsewhere on the body and include the skin and blood vessels, are used to cover the wound and enable it to close and heal properly. A vital step in the process is connecting the blood vessels of the new tissue with those at the site of the wound, so oxygenated blood can reach the new tissue and keep it alive.
Innovative Knee Airbag (KAB) Concept for Small Overlap and Oblique Frontal Impacts2019-01-06214/2/2019
Considerable research has been conducted in terms of attempting to reduce lower leg injury risk in full frontal impacts, in some cases by the use of a knee airbag (KAB). However, there has been limited research into the performance of KAB systems during a crash test with increased oblique loading, such as the IIHS small overlap frontal test, an oblique moving deformable barrier test (OI) being researched by NHTSA, and a mobile progressive deformable barrier test (MPDB) that is expected to be implemented by Euro NCAP in the next few years. The objective of the current numerical study was concentrated on the evaluation of an innovative KAB concept design intended to reduce ATD right inboard lower leg/foot responses under small overlap and oblique loading conditions. A novel appendage KAB concept design was developed with the help of morphing and computational studies which were performed with different ATD sizes. In the study, one of the lower leg/foot responses was monitored and compared over a conventional KAB design. Cases investigated in the study showed that the novel appendage KAB concept design acts as a conventional KAB in full frontal impact modes (similar right inboard femur responses) and has the potential to reduce right inboard lower leg/foot responses by an average 16% (small overlap impact mode) and 20% (oblique impact mode) over the conventional KAB design. Furthermore, it was noted that the novel design could potentially be adapted to achieve targeted right inboard lower leg responses in full, offset and oblique frontal crash tests with minimal impact on the left outboard responses.
Makwana, Rahul, Jindal, Pardeep
Smart Knee Implants Could Reduce Number of Knee Replacement SurgeriesTBMG-339853/1/2019
Smart knee implants may soon be a reality thanks to research done by Binghamton University, Stony Brook University, and the University of Western Ontario.
Rehab Device Works with All Joints of Lower LimbsTBMG-338542/1/2019
South Ural State University Chelyabinsk, Russia
Exoskeleton Device Helps People with Arthritic KneesTBMG-266023/30/2017
A University of North Texas (Denton, TX) graduate student is taking a step toward making exoskeletons available to help more people. Typically, exoskeletons, which are wearable mobile machines that allow for more limb movement, increased strength, and endurance, are extremely expensive and mostly used in the military. However, Jenn Cao, a student in UNT’s College of Engineering, has created a working prototype aimed at helping those who struggle to walk because of osteoarthritis in their knees.
Characterizing Vehicle Occupant Body Dimensions and Postures Using a Statistical Body Shape Model2017-01-04973/28/2017
Reliable, accurate data on vehicle occupant characteristics could be used to personalize the occupant experience, potentially improving both satisfaction and safety. Recent improvements in 3D camera technology and increased use of cameras in vehicles offer the capability to effectively capture data on vehicle occupant characteristics, including size, shape, posture, and position. In previous work, the body dimensions of standing individuals were reliably estimated by fitting a statistical body shape model (SBSM) to data from a consumer-grade depth camera (Microsoft Kinect). In the current study, the methodology was extended to consider seated vehicle occupants. The SBSM used in this work was developed using laser scan data gathered from 147 children with stature ranging from 100 to 160 cm and BMI from 12 to 27 kg/m2 in various sitting postures. A principal component (PC) analysis was conducted based on these scans along with the manually-measured body landmarks, and 100 PC scores were retained to account for 99% of variance in the body shape and sitting postures. A PC-based fast fitting method was applied to estimate the occupant characteristics by fitting the SBSM to an incomplete depth image of a subject. The results demonstrate that a fast, inexpensive system can be used to produce useful estimates of occupant characteristics that could be applied to improve personalization of component adjustments, restraint systems, and infotainment systems.
Park, Byoung-Keon Daniel, Reed, Matthew P.
Researchers Develop 'Gold' Standard for Artificial JointsTBMG-253078/24/2016
Rice University physicists have discovered that a combination of titanium and gold provides a new standard for artificial knee and hip joints.
Knee Monitor 'Listens' for Cracks, PopsTBMG-248716/26/2016
A knee band from the Georgia Institute of Technology uses microphones and vibration sensors to listen to and measure the sounds inside the joint. The sounds will help doctors determine whether a convalescing joint is healthy or requires more therapy.
Low-Cost Prosthetic Knee Mimics Walking MotionTBMG-226958/4/2015
Researchers at the Massachusetts Institute of Technology designed a low-cost prosthetic knee that mimics normal walking motion. The MIT team's prototype generates a torque profile similar to that of able-bodied knees, using only simple mechanical elements like springs and dampers. The team is testing the prosthetic knee in India, an area with approximately 230,000 above-knee amputees.
Improvement and Validation of Hybrid III Dummy Knee Finite Element Model2015-01-04494/14/2015
The public Hybrid III family finite element models have been used in simulation of automotive safety research widely. The validity of an ATD finite element model is largely dependent on the accuracy of model structure and accurate material property parameters especially for the soft material. For Hybrid III 50th percentile male dummy model, the femur load is a vital parameter for evaluating the injury risks of lower limbs, so the importance of accuracy of knee subcomponent model is obvious. The objective of this work was to evaluate the accuracy of knee subcomponent model and improve the validity of it. Comparisons between knee physical model and knee finite element model were conducted for both structure and property of material. The inaccuracy of structure and the material model of the published model were observed. Concentrating on the published dummy knee finite element model, mesh refinement was performed, and the foam material in the front of the knee which does not really exist in knee subcomponent product was replaced by dummy skin material. What's more, a series of uniaxial quasi-static compression tests for Hybrid III 50th percentile male dummy knee skin material and rubber were performed. Material parameters of those materials were fitted using uniaxial quasi-static compression test data. By utilizing Hybrid genetic algorithm, two-order Ogden parameters for skin material and Mooney-Rivlin parameters for rubber insert were obtained respectively. After mesh refinement and material model parameters reassignment, the hourglass of the model in the simulation of knee impact calibration test has been well controlled. The modified knee model was validated by knee impact tests under different velocities, and the relative error between the response of simulation and experiment is less than 5%. A more valid knee finite model of Hybrid III 50th percentile male dummy has been established by using a more accurate model structure and more proper material parameters.
Cao, Libo, Zhang, Kai, Lv, Xin, Yan, Lingbo
User's Manual for the Small Adult Female Hybrid III Test DummyJ2862_201502 (Historical)2/3/2015
This user’s manual covers the small adult female Hybrid III test dummy. It is intended for technicians who work with this device. It covers the construction and clothing, disassembly and reassembly, available instrumentation, external dimensions and segment masses, as well as certification and inspection test procedures. It includes instructions for safe handling of the instrumented dummy, repairing dummy flesh, and adjusting the joints throughout the dummy.
Dummy Testing and Equipment Committee
Hydraulic Prosthetic Knee Joints Provide More Natural Mobility for PatientsTBMG-202508/1/2014
For patients who have lost a leg, regaining mobility is a top priority. However, development of more true-to-nature prosthetic limbs and joints has come an amazingly long way from the often thought of peg leg and hook hand. Over the past several years, medical prosthetic technology has advanced drastically, allowing for patients to regain the normalcy in their life that they would not have had access to in the past.
Comparison of Femur Moments and Forces of EEVC WG17 Upper Leg Impactor, FlexPLI and Human Body Finite Element Model2014-01-05154/1/2014
EEVC WG17 Upper Leg impactors have been used to assess the risk of pedestrian upper leg injuries with respect to regulatory and consumer metric rating requirements. The paper compares the femur injury responses between the finite element models of the EEVC WG17 Upper Leg impactor, the FlexPLI and the 50th percentile male GM/UVa pedestrian model on two sample vehicle architectures, for a sedan and a sports utility vehicle. The study shows that the peak femur load and maximum bending moment response are higher in the EEVC WG17 Upper Leg impactor than the FlexPLI and the human body model. Variation studies are carried out to study the influence of impact location on the vehicle, impactor knee height, additional upper body mass and human body model size on the femur injury responses. The FlexPLI femur responses correlate better with those of the human body model and indicate that the impactor has the potential to be an effective surrogate leg form of a pedestrian with appropriate refinement.
Baviskar, Tushar, Mahadevaiah, Jagadish, Iyer, Vijay Shankar, Neal, Mark
Implantable Spring for Knee OsteoarthritisTBMG-188751/1/2014
Healthy joints and cartilage are exposed to mechanical loads during everyday motion and activity. While normal joint loading can help maintain joint tissues, high loading due to obesity, or abnormal loading due to anatomy or trauma can contribute to microfractures, bone thickening, and cartilage degradation. Many osteoarthritis (OA) therapies only provide short-term pain relief or repair focal cartilage damage. When the biomechanics behind joint overload are left untreated, however, the patient may suffer through several rounds of unsuccessful therapies until he or she is a candidate for knee replacement surgery.
2013 Create the Future Design: Medical Category WinnerTBMG-1774011/1/2013
Flex-PLI Application to High-Bumper Vehicles - Optimization of Supplemental Weight2013-01-02154/8/2013
The Flexible Pedestrian Legform Impactor (Flex-PLI) was developed to evaluate the risk of pedestrian lower extremity injuries. However, it has been pointed out that the post-crash kinematics of the Flex-PLI differs from those of a human body when it is hit by high-bumper vehicles. This paper describes the feasibility of applying the Flex-PLI to a wide range of vehicle types by adding a supplemental weight. The following aspects are discussed in this regard: A human body finite element (FE) model analysis shows that the upper body of the Flex-PLI is not involved in tibia and knee ligament injury indexes in the first contact with a high-bumper vehicle. A rigid bar model is introduced and its rotational energy ratio is formulated. The rotational energy ratio is employed to evaluate the post-crash kinematics of the Flex-PLI and a human leg model. The feasibility of adding a supplemental weight to the Flex-PLI with regard to the bumper height is discussed.
Kawabe, Yoshiko, Pal, Chinmoy, Okuyama, Hiroyuki, Okabe, Tomosaburo
Hybrid III 50 th Dummy Ankle Performance Study and Proposed Design Modification2013-01-06644/8/2013
The Hybrid III 50th male dummy[1] is used globally in vehicle safety for measuring the damage index of dummy components. This paper focuses on the dummy's ankle structures which have a great effect on its tibia index (TI). It is found that the ankle shaft can be damaged during the regular EURO and China NCAP[2] [3] front offset deformable barrier (ODB) test, which affects the accuracy of TI and the corresponding evaluation score. This paper studies the ankle structure and the component material properties and proposes a design modification to prevent damage to the ankle shaft.
Li, Lihua, Zhao, Youmei, Shen, Guangyong
Medical Category WinnerTBMG-1511511/1/2012
The Medical winner was simply named Prosthetic Leg Connector. Its simplistic name belies the amount of thought and care that went into the creation of a device to replace the traditional silicone rubber “sock” that is pulled very snugly over a residual limb before attaching an artificial leg.
User's Manual for the Hybrid III Large Male Test DummyJ2860_201209 (Historical)9/27/2012
This SAE Surface Vehicle Information Report identifies and defines the assembly/disassembly and certification procedures relating to the use of the Hybrid III Large Male Test Dummy.
Dummy Testing and Equipment Committee
Improving Balance Function Using Low Levels of Electrical Stimulation of the Balance OrgansTBMG-146189/1/2012
Crewmembers returning from long duration space flight face significant challenges due to the microgravity induced inappropriate adaptations in balance/sensorimotor function. The Neuroscience Laboratory at JSC is developing a method based on stochastic resonance to enhance the brain’s ability to detect signals from the balance organs of the inner ear and use them for rapid improvement in balance skill, especially when combined with balance training exercises. This method involves a stimulus delivery system that is wearable/ portable providing imperceptible electrical stimulation to the balance organs of the human body.
Inspection for Perfection: How 3D Surface Profiling Tools Aid Implant ManufacturersTBMG-143458/1/2012
Surface texture and shape play critical roles in the successful integration, lifetime, and effectiveness of bioimplantable devices. A variety of techniques is available to quantify the surface characteristics. Non-contact, 3D optical profiling using scanning white light interferometry (SWLI) is of growing interest for quantifying these critical characteristics. The NewView™, ZeGage™, and ZeScope™ systems from Zygo Corporation (Middlefield, CT) exemplify this class of surface analysis instrumentation.
Polymer Biomaterials Offer Possibilities for Orthopedic ImplantsTBMG-136035/1/2012
Since the 1950s and John Charnley’s introduction of the low friction hip prosthesis, metal-on-polyethylene bearings have remained the gold standard in terms of the long-term performance of orthopedic implants, and have represented the largest share of the orthopedic implant market. In spite of decades of use and large amounts of research and development on these materials, some problems still exist with this material combination. Prime among these are wear-related osteolysis and thick implants leading to healthy bone removal during surgery. The use of a high-performance polymer material may present an opportunity to create a step change in this sector.
Light Source Enables Endoscope MiniaturizationTBMG-135895/1/2012
Physical space constraints continue to impact advanced procedures such as single-incision laparoscopic surgery, robotic-assisted surgery, and other minimally invasive surgical procedures. Additional functionality and instruments are being squeezed through the smallest incisions possible. Available space continues to tighten with the migration of larger diameter, three-dimensional, high-definition endoscopic imaging systems into minimally invasive procedures. Fortunately, a significant portion of the endoscope, the light delivery channel, can be reduced in size, thereby allowing the space to be used for other purposes, or for shrinking the endoscope itself.1
Wireless Tags Quickly Provide Details About Orthopedic ImplantsTBMG-135955/1/2012
Radio-frequency technology that uses human tissue instead of air as a conduit for radio waves is the basis of the first electronic “tag” system designed to track and monitor orthopedic implants. A 2009 RAND Corporation (Europe) technical report found that RFID technology offers several advantages to medical care in such areas as wireless data transfer and patient/object identification, and as a sensor.
Wearable, Artificially Intelligent, Bionic DeviceTBMG-102356/1/2011
eLEGS is a wearable, artificially intelligent, bionic device that enables people with paralysis to stand up and walk again. The exoskeleton is battery-powered and rechargeable, fitting comfortably and securely over clothing.
Experimental Walking Assist Device With Body Weight Support SystemTBMG-102336/1/2011
An experimental walking assist device has been developed to help support body weight and reduce the load on the user’s legs while walking, going up and down stairs, and in a semi-crouching position. The device reduces the load on leg muscles and joints (in the hip, knees, and ankles) by supporting a portion of the person’s body weight. It features a simple structure consisting of seat, frame, and shoes, and the user can put it on by simply wearing the shoes and lifting the seat into position. Moreover, a mechanism that directs the assisting force toward the user’s center of gravity and the ability to control the assist force in concert with the movement of the legs make it possible for the device to provide natural assistance in various postures and motions.
Laser Sintering for Customized Medical ApplicationsTBMG-99215/1/2011
Engineers have long been aware of the potential of laser sintering to create innovative and beneficial medical products. Because it is an additive (layer-by-layer) manufacturing process, laser sintering can build parts free of the traditional constraints imposed by machining or molding.
Lockable Knee Brace Speeds RehabilitationTBMG-81377/1/2010
Marshall Space Flight Center develops key transportation and propulsion technologies for the Space Agency. The Center manages propulsion hardware and technologies of the space shuttle, develops the next generation of space transportation and propulsion systems, oversees science and hardware development for the International Space Station, manages projects and studies that will help pave the way back to the Moon, and handles a variety of associated scientific endeavors to benefit space exploration and improve life here on Earth.
User's Manual for the 50th Percentile Male Hybrid III DummyJ2856_200909 (Historical)9/17/2009
The purpose of this document is to provide the user with the procedures needed to properly assemble and disassemble the 50th percentile male Hybrid III dummy, certify its components and verify its mass and dimensions. Also within this manual are guidelines for handling accelerometers, repairing flesh and setting joints.
Dummy Testing and Equipment Committee
Surgical Robots Provide Helping “Hands” in the ORTBMG-64965/1/2009
As human beings become more comfortable sharing their space with robots, we can expect that robotic technologies will infiltrate even more aspects of our lives. For the past decade or so, robotic systems for surgery have been tested, approved by the U.S. Food and Drug Administration (FDA), and used successfully to perform operations that previously required highly invasive surgical procedures. Robotic systems have been used in tens of thousands of procedures including general, urologic, gynecologic, and cardiac procedures such as mitral valve repair.
Estimation of Knee Ligament Injury Measures for a Pedestrian Dummy2009-01-12124/20/2009
In order to enhance understanding of pedestrian injury mechanisms, full-body pedestrian dummies have been developed in past studies. The goal of this study was to estimate knee ligament injury measures for a pedestrian dummy based on the correlation between dummy and human responses. For estimating knee ligament force of the dummy approximating the average ligament failure, finite element (FE) human and dummy knee joint models were subjected to dynamic 4-point bending. The estimated measures for the modified dummy knee ligaments were 3.0, 0.5 and 1.1 kN for the MCL, PCL and ACL, respectively. A full-body FE dummy model was subjected to impacts from a small sedan and a Sport Utility Vehicle (SUV) for validating the estimated force levels. The results showed that the estimated dummy knee ligament force levels predicted failure of human knee ligaments that is likely to take place first when leg fractures are not present in impacts from a small sedan and a SUV.
Takahashi, Yukou, Okamoto, Masayoshi, Akiyama, Akihiko, Kikuchi, Yuji
Experimental Study of Variation between Quasi-static and Dynamic Load Deformation Properties of Bovine Medial Collateral Ligaments2009-01-03924/20/2009
In a significant number of automobile crashes involving pedestrians, the ligaments which control the stability of the knee, often get severely loaded. In lateral impact on knee during automotive crashes, varus-valgus motion results in failure of ligament by avulsion or by rupture in the middle region It is known that properties vary in different regions of the ligament. Experimental measurement of tensile load-elongation behavior of the middle region of bovine medial collateral ligament at strain rates of 10−4 /s to 160/s are reported here. The results show that the stress-strain behavior is linear under quasi-static loading whereas it is nonlinear and strain rate sensitive in dynamic loading conditions.
Warhatkar, Hemant, Chawla, Anoop, Mukherjee, Sudipto, Malhotra, Rajesh
Dashboard Stiffness Control for Reducing Knee Injury in Frontal Crashes2009-26-00061/21/2009
In frontal crashes, one of the primary reasons for occupant injuries is hard contact with the vehicle interiors. While restraints like airbags, seat belt pre-tensioners etc. help in preventing direct contact of the upper body region; vehicle interiors play a critical role in controlling the lower body region injuries. Knee injuries can be controlled in various ways as follows: Avoiding contact with the dashboard by use of buckle pre-tensioners etc. Using restraints like knee airbags Optimizing the dashboard profile and stiffness at the contact locations All the above options have their own advantages and limitations. This paper explains the effect of dashboard stiffness tuning for controlling knee injuries in a frontal crash. The development methodology and some validation tools are discussed using a case study.
Gokhale, Ajit V., Saravate, Vithoba, Kshirsagar, Sarang
Functional Joint Rotation Centers for Whole Body Digital Manikin2008-01-18596/17/2008
In order to adapt actual motion data of a person to a digital manikin, we developed a method of estimating the functional joint rotation centers for the whole manikin body. By using this method, the positions of joints in motion can be estimated if the length of each segment of the whole body remains constant. As a result, when the digital model of the whole body moves, the trajectory of the most distal end is more similar to that of an actual human than the trajectory of the whole body model estimated using a conventional method.
Aoki, Kei, Kawachi, Katsuaki, Kouchi, Makiko, Mochimaru, Masaaki
Pedestrian Lower Extremity Response and Injury: A Small Sedan vs. A Large Sport Utility Vehicle2008-01-12454/14/2008
Vehicle front-end geometry and stiffness characteristics have been shown to influence pedestrian lower extremity response and injury patterns. The goal of this study is to compare the lower extremity response and injuries of post mortem human surrogates (PMHS) tested in full-scale vehicle-pedestrian impact experiments with a small sedan and a large sport utility vehicle (SUV). The pelves and lower limbs of six PMHS were instrumented with six-degree-of-freedom instrumentation packages. The PMHS were then positioned laterally in mid-stance gait and subjected to vehicle impact at 40 km/h with either a small sedan (n=3) or a large SUV (n=3). Detailed descriptions of the pelvic and lower extremity injuries are presented in conjunction with global and local kinematics data and high speed video images. Injured PMHS knee joints reached peak lateral bending angles between 25 and 85 degrees (exceeding published injury criteria) at bending rates between 1.1 deg/ms and 3.7 deg/ms. In one case, the onset of tibia and fibula fracture may have prevented ipsilateral knee joint injury. Overall, the SUV appeared to be more aggressive than the sedan in causing injuries to the lower extremities and the pelvis of the tested PMHS.
Kerrigan, Jason, Subit, Damien, Untaroiu, Costin, Crandall, Jeff, Rudd, Rodney
Sign Convention for Vehicle Crash TestingJ1733_200711 (Current)11/2/2007
In order to compare test results obtained from different crash test facilities, standardized coordinate systems need to be defined for crash test dummies, vehicle structures, and laboratory fixtures. In addition, recorded polarities for various transducer outputs need to be defined relative to positive directions of the appropriate coordinate systems. This SAE Information Report describes the standardized sign convention and recorded output polarities for various transducers used in crash testing.
Safety Test Instrumentation Standards Committee
Optimal Design of Instrument Panel for Euro NCAP2007-01-37218/5/2007
In order to obtain EURO NCAP 5★, it is essential to avoid the knee modifier (Variable Contact Modifier and Concentrated Loading Modifier). This paper, euro-type Instrument panel structure which can avoid the knee modifier was proposed, and CAE was performed for structural optimization. Proposed euro-type Instrument panel can cause the problems (the head impact failure, static load failure, idle resonance). In order to solve these problems and to account for these phenomena at the early design stages, CAE simulating tool was proposed and developed.
Jae, Kwon Hyuk, Sik, Bae Jong, Wan, Woo Chang
Retrieval and Clustering from a 3D Human Database based on Body and Head Shape2006-01-23557/4/2006
In this paper, we describe a framework for similarity based retrieval and clustering from a 3D human database. Our technique is based on both body and head shape representation and the retrieval is based on similarity of both of them. The 3D human database used in our study is the CAESAR anthropometric database which contains approximately 5000 bodies. We have developed a web-based interface for specifying the queries to interact with the retrieval system. Our approach performs the similarity based retrieval in a reasonable amount of time and is a practical approach.
Godil, Afzal, Ressler, Sandy
The Role of Visual and Manual Demand in Movement and Posture Organization2006-01-23317/4/2006
The organization of upper body and gaze movements was quantified as an attempt to identify the types of task descriptors associated with the visual and manual functions of movement control. Nine subjects were asked to either read a word (high visual demand), reach a target (low visual demand), or simultaneously read a word and reach the object target placed just below the word (high visual demand). Similarly the manual demand condition was either low or high, depending on the target distance from the shoulder (either 80 or 120% of extended arm length, respectively). Torso flexion and gaze-on-target duration showed that movements are influenced by the both visual and manual demands in an interactive manner. Also both torso posture and gaze movements were predominantly changed by the visual demand. These results suggest that tasks to be simulated should be described in terms of both visual and manual demand.
Kim, K. Han, Martin, Bernard J., Dukic, Tania, Hanson, Lars
Ergonomic Layout Process for a Driver Working Place in Cars2006-01-23137/4/2006
During early phases of interior car layout a lot of different aspects have to be considered like crashworthiness, regulations, philosophy of the company etc.. Ergonomic aspects do not always play the most important role in these cases. Since aspects of comfort in cars are getting more and more important in nowadays these aspects should be taken into account very early in the interior car layout process. This paper shows a way to design the interior layout of a car from scratch for a good postural comfort for all anthropometries with the aid of a digital human model (RAMSIS). The novelty of this approach is to use the digital human model to design the interior and not to verify or correct an existing one.
Mergl, Christian, Bubb, Heiner, Vogt, Christian, Kress, Holger
Strength and Balance Guided Posture Selection during a Battery Maintenance Task2006-01-06984/3/2006
Posture selection during standing exertions is a complex process involving tradeoffs between muscle strength and balance. Bodyweight utilization reduces the amount of upper-body strength required to perform a high force push/pull exertion but shifts the center-of-gravity towards the limits of the functional stability region. Thus balance constraints limit the extent to which bodyweight can be used to generate push/pull forces. This paper examines a two-handed sagittal plane pulling exertion performed during a battery maintenance task on a member of the family of medium-sized tactical vehicles (FMTV). Percent capable strength predictions and functional balance capabilities were determined for various two-handed pulling postures using the University of Michigan's 3D Static Strength Prediction Program (3DSSPP). Through this simulation study, preferred postures that minimize joint torques while maintaining balance were identified. Such preferred postures are important in redesigning the vehicle for improved maintenance.
Hoffman, Suzanne G., Chaffin, Don B., Wagner, David W.
Effect of Active Muscle Forces on the Response of knee Joint at Low Speed Lateral Impacts2006-01-04604/3/2006
In vehicle-pedestrian collisions, lower extremities of pedestrians are frequently impacted by the vehicle front structure. The aim of the current study is to understand the role of muscle activity in knee joint injuries at low velocity lateral impacts, characteristic of vehicle-pedestrian collisions. Therefore, a group of muscles in the lower extremity are modeled using bar elements with the Hill material model. The reflex response of the muscle is then included. Simulations indicate that muscle activation decreases the probability of failure in knee ligaments.
Soni, Anurag, Chawla, Anoop, Mukherjee, Sudipto
Stairs on the Moon2005-01-30467/11/2005
This paper is an adaptation from a master’ thesis about the architectural design responses to the body's adaptations to a reduced gravity environment. The thrust of this extraction is to study the architectural and biomechanics of stairs in a 1/6 g environment as opposed to a 1 g environment. This paper discusses the ramifications of going up stairs, ramps, and loping considerations such as head height adjustments. Forces, center of gravity, friction, momentum, biomechanics of the knee and hip, and the height from the ground achieved by loping on the moon are discussed. There is also a discussion of stairs vs. ladders as well as the synthesizing of the two modes of vertical circulation.
Barnes, Annette M.
Characterization of the Rate-Dependent Mechanical Properties and Failure of Human Knee Ligaments2005-01-02934/11/2005
The structural properties of the four major human knee ligaments were investigated at different loading rates. Bone-ligament-bone specimens of the medial and lateral collateral ligaments and the anterior and posterior cruciate ligaments, obtained from post-mortem human donors, were tested in knee distraction loading in displacement control. All ligaments were tested in the anatomical position corresponding to a fully extended knee. The rate dependence of the structural response of the knee ligaments was investigated by applying loading-unloading cycles at a range of distraction rates. Ramps to failure were applied at knee distraction rates of 0.016 mm/s, 1.6 mm/s, or 1,600 mm/s. Averages and corridors were constructed for the force response and the failure point of the different ligaments and loading rates. The structural response of the knee ligaments was found to depend on the deformation rate, being both stiffer and more linear at high loading rates. This rate dependence was found to be more pronounced at high loading rates.
van Dommelen, J.A.W., Ivarsson, B.J., Minary Jolandan, M., Millington, S.A., Raut, M., Kerrigan, J.R., Crandall, J.R., Diduch, D. R.
Ex Vivo Growth of Bioengineered Ligaments and Other TissuesTBMG-2413/1/2005
A method of growing bioengineered tissues for use in surgical replacement of damaged anterior cruciate ligaments has been invented. An anterior cruciate ligament is one of two ligaments (the other being the posterior cruciate ligament) that cross in the middle of a knee joint and act to prevent the bones in the knee from sliding forward and backward relative to each other. Anterior cruciate ligaments are frequently torn in sports injuries and traffic accidents, resulting in pain and severe limitations on mobility. By making it possible to grow replacement anterior cruciate ligaments that structurally and functionally resemble natural ones more closely than do totally synthetic replacements, the method could create new opportunities for full or nearly full restoration of functionality in injured knees. The method is also adaptable to the growth of bioengineered replacements for other ligaments (e.g., other knee ligaments as well as those in the hands, wrists, and elbows) and to the production of tissues other than ligaments, including cartilage, bones, muscles, and blood vessels.
Estimating Low Back Loads of Underground Mine Roof Bolter Operators using Digital Human Simulations2004-01-21486/15/2004
NIOSH researchers conducted a study to evaluate the severity of muscle recruitment and spine loads resulting from performance of the roof bolting cycle in different work postures and mine seam heights. Ten male and two female subjects performed three repetitions of a mine roof bolting in each of seven posture/seam height combinations, while researchers obtained motion data of their actions using a motion capturing system. A database containing forces on L4/L5 spinal joint and on back muscles was generated by processing the captured motions from each subject using UGS PLM Solution Jack software’s task analysis toolkit – lower back analysis. An analysis of variance was performed using the maximum values for spinal forces and moments and estimated muscle forces for ten trunk muscles in the resulting database. Results of this study indicate that the roof bolter operator’s standing posture significantly increases the forward bending moment, compression force and trunk muscle activity more than either kneeling posture. Also the kneeling postures in a 45-inch seam height significantly increases, compared to a 60-inch seam height, the forward bending moment, twisting moment, compression force, and trunk muscle activity for lateral movements and extending the torso. Impact: Mining industry can use this information to reduce loads on the low back through better work postures from redesigning the machine’s workstation and modifying bolting cycle work procedures.
Ambrose, Dean H., Cole, Gregory P., Gallagher, Sean
Validation of a Load Carriage Simulation2004-01-21716/15/2004
This paper presents a validation study of a physics-based simulation of human walking. We simulated four different subjects walking on the level with nine different backpacks. Compared against experimental data of subjects under the same conditions, simulation results are shown to predict peak ground reaction forces, joint angles, and the subjects’ adjustment to lean angle necessary to dynamically balance the load and achieve stable walking at 1.4 m/s.
Layon, Antonio Y., de Lasa, Martin, Playter, Robert, Talebi, Shervin, LaFiandra, Michael, Piscitelle, Louis, Obusek, John
An Inverse Model Based on Optimization in order to Simulate the Automobile Accessibility Movement – A Pilot Study2004-01-21746/15/2004
An experimental protocol and device were setup in order to record the automobile accessibility movement and a biomechanical human model composed of articulated rigid bodies was proposed to reproduce it. From the trajectories of the hands and the feet, an optimization method is applied to each kinematic chain of the model to find the joint angles. It minimizes, for each phase of the automobile accessibility movement, the Euclidian distance between the real and simulated trajectories of the hands and the feet. The constraints take into account the extremes of the experimental joint angles values and the maximum joint variation between two consecutive instants. The first results show that the simulated trajectories of the end effectors fit to the real trajectories but a difference between the computed and simulated joint angles remains.
Lempereur, M., Pudlo, P., Lepoutre, F.-X., Gorce, P.
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