Biomechanics Commons^™

Effects Of Knee Bracing On Vertical Jumping Performance In Healthy College Aged Males, Rebecca E. Rausch

All-Inclusive List of Electronic Theses and Dissertations

Knee bracing is used at all levels of athletics to prevent or support existing knee injuries; however, little research has been conducted on the effects of knee braces on athletic performance. Therefore, the purpose of this study was to examine how two different types of knee braces, semi-customizable braces and knee sleeves, affect vertical jumping performance. Subjects were nine college aged males who regularly participated in athletic activity. Subjects performed a task consisting of a drop jump from a height of 18 inches, landing in a squat position, followed immediately by a maximal vertical jump while wearing two different knee …

Effects Of An Angled Starting Block On Sprint Start Kinematics, Nathaniel A. Brown

All-Inclusive List of Electronic Theses and Dissertations

The purpose of the present study was to investigate the effects of an angled proto-type starting block on sprint start kinematics. The angled starting block rotates the foot medially at a 16 degree angle, which emulates the 16 degree angle of the ankle on the medial axis of the foot. This 16 degree should allow for the athlete to apply more force against the block, resulting in a higher velocity at take-off and a faster block clearance time. In the present study, six female collegiate sprinters were filmed and analyzed using the angled starting block and a standard starting block. …

Acl Deficiency Affects Stride-To-Stride Variability As Measured Using Nonlinear Methodology, Constantina O. Moraiti, Nikolaos Stergiou, Stavros Ristanis, Anastasios D. Georgoulis

Journal Articles

Previous studies suggested that the small fluctuations present in movement patterns from one stride to the next during walking can be useful in the investigation of various pathological conditions. Previous studies using nonlinear measures have resulted in the development of the “loss of complexity hypothesis” which states that disease can affect the variability and decrease the complexity of a system, rendering it less able to adjust to the ever changing environmental demands. The nonlinear measure of the Lyapunov Exponent (LyE) has already been used for the assessment of stride-to-stride variability in the anterior cruciate ligament (ACL) deficient knee in comparison …

Approximate Entropy Detects The Effect Of A Secondary Cognitive Task On Postural Control In Healthy Young Adults: A Methodological Report, James T. Cavanaugh, Vicki S. Mercer, Nikolaos Stergiou

Journal Articles

Background: Biomechanical measures of postural stability, while generally useful in neuroscience and physical rehabilitation research, may be limited in their ability to detect more subtle influences of attention on postural control. Approximate entropy (ApEn), a regularity statistic from nonlinear dynamics, recently has demonstrated relatively good measurement precision and shown promise for detecting subtle change in postural control after cerebral concussion. Our purpose was to further explore the responsiveness of ApEn by using it to evaluate the immediate, short-term effect of secondary cognitive task performance on postural control in healthy, young adults.

Methods: Thirty healthy, young adults performed a modified version …

Peripheral Arterial Disease Affects Ground Reaction Forces During Walking, Melissa Scott-Pandorf, Nikolaos Stergiou, Jason Johanning, Leon Robinson, Thomas G. Lynch, Iraklis Pipinos

Journal Articles

Objective: Claudication is the most common manifestation of peripheral arterial disease (PAD), producing significant ambulatory compromise. The gait of claudicating patients has been evaluated using primarily temporal and spatial parameters. With the present study, we used advanced biomechanical measures to further delineate the ambulatory impairment of claudicating patients. We hypothesized that the claudicating legs of PAD patients have an altered kinetic gait pattern compared with normal legs from control subjects.

Methods: Ambulation kinetics (ground reaction forces) were evaluated in claudicating patients and compared with age-matched healthy controls. Forces were analyzed in the vertical, anterior–posterior, and medial–lateral directions. Time from heel …

Do Horizontal Propulsive Forces Influence The Nonlinear Structure Of Locomotion?, Max J. Kurz, Nikolaos Stergiou

Journal Articles

Background: Several investigations have suggested that changes in the nonlinear gait dynamics are related to the neural control of locomotion. However, no investigations have provided insight on how neural control of the locomotive pattern may be directly reflected in changes in the nonlinear gait dynamics. Our simulations with a passive dynamic walking model predicted that toe-off impulses that assist the forward motion of the center of mass influence the nonlinear gait dynamics. Here we tested this prediction in humans as they walked on the treadmill while the forward progression of the center of mass was assisted by a custom built …

Fabrication Of Ankle-Foot Orthoses Using Selective Laser Sintering Technology, Allison Kinney, M. C. Faustini, Richard R. Neptune, R. H. Crawford, S. J. Stanhope

Mechanical and Aerospace Engineering Faculty Publications

Passive dynamic ankle-foot orthoses (AFOs) are often prescribed to improve gait performance for those with various neuromuscular disorders. Designs and materials used for AFOs range from simple polypropylene braces to advanced custom carbon fiber dynamic AFOs that passively store and release mechanical energy during gait. AFO designs vary in the shape and length of the foot component as well as the stiffness and length of the tibial component, depending on the desired functional outcomes. However, the current fabrication technology is not ideally suited for refined customization of AFO characteristics to optimize performance, or for rapid lowcost, high volume manufacturing and …

Development And Analysis Of A Software Package To Quantify In Vivo Polyethylene Wear After Total Hip Arthroplasty, Allison Kinney, Catherine G. Ambrose

Mechanical and Aerospace Engineering Faculty Publications

Since the first total hip arthroplasty (THA) in 1938, THA evolved and developed into one of the major concentrations of orthopaedic research. The typical hip implant device used today incorporates a femoral and an acetabular component that serve to replicate the anatomical and mechanical functions of the natural hip joint. However, several problems exist that can effect the function of the implant device. Wear in the polyethylene liner of the acetabular component of the total hip replacement device is known as one of the major factors that affects the longevity of total hip replacement devices. Both manual and computer-aided techniques …

Tibial Rotation In Anterior Cruciate Ligament (Acl)-Deficient And Acl-Reconstructed Knees, Nikolaos Stergiou, Stavros Ristanis, Constantina O. Moraiti, Anastasios D. Georgoulis

Journal Articles

Excessive tibial rotation has been documented in ACL deficiency during walking. ACL reconstruction has been unable to correct this abnormality in activities that are more demanding than walking and involve both anterior and rotational loading of the knee. These findings persist regardless of graft selection for the ACL reconstruction [bone-patellar tendon-bone (BPTB) or semitendinosus-gracilis (ST/G)]. Based on this research work, we propose a theoretical perspective for the development of osteoarthritis in both the ACL deficient and the ACL reconstructed knee. We propose that excessive tibial rotation will lead to abnormal loading of the cartilage areas that are not commonly loaded …

Hper Biomechanics Laboratory 2006 Annual Report, Issue 5, Nebraska Biomechanics Core Facility

Biomechanics Annual Report

This issue features Peripheral Arterial Disease and Geriatrics Research Update, Lab Expands with New Personnel, Labor on NIH Grant Is, “Gratifying Labor” States Dr. Stergiou, Federal Grant On Cerebral Palsy: Joint Venture Demonstrates Progress, Evolution of Wireless Gait Analysis, Innovations of Robotic Assisted Surgery Research, Incorporating Virtual Reality, Events in the Lab, Dr. Stergiou Awarded Outstanding Graduate Mentor , Collaborations in Orthopedics, The Media Features Efforts in HPER Biomechanics Lab , Other Continuing Collaborations, Other Exciting News, Publications for 2006 and The 2006-2007 HPER Biomechanics Laboratory.

Methods To Improve The Reliability Of The Functional Reach Test In Children And Adolescents With Typical Development, Kathleen G. Volkman, Nikolaos Stergiou, Wayne A. Stuberg, Daniel Blanke, Julie Stoner

Journal Articles

Purpose: Test-retest reliability of the Functional Reach Test was examined in children with typical development by comparing standard and alternate methods.

Methods: Eighty subjects ages seven to 16 years were tested and 69 retested for four methods of Functional Reach Test (ie, one-arm finger-to-finger, two-arm finger-to-finger, one-arm toe-to-finger, and two-arm toe-to-finger). Intraclass correlation coefficients and limits of agreement were calculated.

Results: Intraclass correlation coefficients were high in toe-to-finger measurement methods (0.97– 0.98) for the entire group and specific age groups (00.83–0.93). Toe-to-finger methods were more reliable than finger-to-finger methods. The two-arm toe-to-finger method had the best limis of agreement with …

Herodicus, The Father Of Sports Medicine, Anastasios D. Georgoulis, Irini-Sofia Kiapidou, Lamprini Velogianni, Nikolaos Stergiou, Arthur Boland

Journal Articles

Herodicus (fifth century bc) is the first person in the history of medicine who actually combined sports with medicine. He used to be a sports teacher, who later studied medicine and managed to succeed Euryphon in the medical school of Cnidos, one of the most prominent in ancient Greece together with its neighbor medical school of Cos (Hippocrates’ home). In Cnidos Herodicus formed his own theoretical perspective of medicine. He considered, namely, bad health to be the result of imbalance between diet and physical activity and for this reason he recommended strict diet, constant physical activity and regular training. He …

High Dietary Fat Intake Is Not Associated With High Levels Of Circulating Lipoproteins Or Total Cholesterol, C. Jayne Brahler, C. Wilson, Janine Baer

Physical Therapy Faculty Publications

The objective of this study was to determine the association between dietary intake of fats, waist to hip ratio (WHR), body mass index (BMI), and blood lipoproteins and total cholesterol (TC) using food frequency data in one group of apparently healthy, urban African American women and their daughters (n = 110). Subjects were fasted when blood was drawn, waist and hip circumferences and body weight and height were measured, and WHR and BMI were calculated.

Average daily total fat intakes were 91.46 g and 77.83 g for mothers and daughters, respectively, but average LDL levels of 104.4 g/L and 103.1 …

Medicine Meets Virtual Reality 15, James D. Westwood, Matthew J. Fieldler, Shing-Jye Chen, Timothy N. Judkins, D. Oleynikov, Nikolaos Stergiou

Faculty Books and Monographs

Chapter, Virtual Reality for Robotic Laparoscopic Surgical Training, co-authored by Nicholas Stergiou, UNO faculty member.

Our culture is obsessed with design. Sometimes designers can fuse utility and fantasy to make the mundane appear fresh—a cosmetic repackaging of the same old thing. Because of this, medicine—grounded in the unforgiving realities of the scientific method and peer review, and of flesh, blood, and pain—can sometimes confuse “design” with mere “prettifying.” Design solves real problems, however. This collection of papers underwrites the importance of design for the MMVR community, within three different environments: in vivo, in vitro and in silico. in vivo: we …

Tibial Rotation Is Not Restored After Acl Reconstruction With A Hamstring Graft, Anastasios D. Georgoulis, Stavros Ristanis, Vasileios Chouliaras, Constantina O. Moraiti, Nikolaos Stergiou

Journal Articles

Recent research suggests ACL reconstruction does not re- store tibial rotation to normal levels during high demand activities when a bone-patellar tendon-bone graft is used. We asked if an alternative graft, the semitendinosus-gracilis (ST/G) tendon graft, could restore tibial rotation during a high demand activity. Owing to its anatomic similarity with the normal ACL we hypothesized the ST/G graft could re- store excessive tibial rotation to normal healthy levels along with a successful reinstatement of the clinical stability of the knee. We assessed tibial rotation in vivo, using gait analysis. We compared the knees of ACL reconstructed patients with an …

Kinetic And Kinematic Analysis Of A Judo Throwing Technique: Osoto-Gari, Noriko Narazaki, Kenji Narazaki, Nicholas Stergiou

Journal Articles

No abstract provided.

Effectiveness Of Reconstruction Of The Anterior Cruciate Ligament With Quadrupled Hamstrings And Bone-Patellar Tendon-Bone Autografts: An In Vivo Study Comparing Tibial Internal-External Rotation, Vasileios Chouliaras, Stavros Ristanis, Constantina Moraiti Moraiti, Nikolaos Stergiou, Anastasios D. Georgoulis

Journal Articles

Background: The 2 most frequently used autografts for anterior cruciate ligament reconstruction are the bone-patellar tendon- bone and the quadrupled hamstrings tendon.

Hypothesis: Hamstring tendon graft is superior to patellar tendon graft in restoring tibial rotation during highly demanding activities because of its superiority in strength and linear stiffness and because it is closer morphologically to the anatomy of the natural anterior cruciate ligament.

Study Design: Case control study; Level of evidence, 3.

Methods: Eleven patients with patellar tendon graft anterior cruciate ligament reconstruction, 11 patients with hamstring tendon graft anterior cruciate ligament reconstruction, and 11 …

Objective Assessment Of Proficiency With Bimanual Inanimate Tasks In Robotic Laparoscopy, Kenji Narazaki, D. Oleynikov, Nikolaos Stergiou

Journal Articles

Purpose: Development of objective criteria and optimum training protocols are priorities for robotic laparoscopy. However, studies that have attempted to objectify learning have been limited due to lack of task complexity and absence of comparisons between experts and novices. Our aim was to address these limitations and assess proficiency in robotic laparoscopy using bimanual inanimate tasks.

Materials and Methods: Six experts and 18 novice users of the da Vinci surgical system (Innovative Surgical, Sunnyvale, CA) performed three bimanual surgical manipulations, two of them in opposite directions, for a total of five different test tasks. During each task, elapsed time and …