Stuart A. Binder-Macleod, Ph.D., PT 

Dr. Binder-Macleod's research focuses on the neural control of skeletal muscle force output.  He currently is attempting to identify the most efficient stimulation patterns that minimize fatigue in patients with spinal cord injuries. The loss of motor control due to central nervous system (CNS) trauma can be both a psychologically and physically devastating injury. One limiting factor in the clinical application of electrical stimulation is the rapid skeletal muscle fatigue that accompanies its use.  Identifying stimulation patterns that minimize fatigue should increase the clinical usefulness of functional electrical stimulation.

Dr. Binder-Macleod's work has shown that varying the stimulation frequency within a brief train of pulses can produce greater forces from the muscle than the traditionally used constant-frequency trains. Current work is exploring how the optimal pattern of activation varies under a variety of physiological conditions including: fatigue state of the muscle, muscle length, load, and velocity of muscle shortening and lengthening.

Dr. Binder-Macleod is currently funded by two grants from the NIH to support this work.  The first grant is a four-year $1.1 million renewal that has support his work for the past ten years.  The second grant is a five-year $3.1 million Bioengineering Research Partnership that was recently awarded to the Physical Therapy and Mechanical Engineering Departments at the University of Delaware. 

Dr. Binder-Macleod is also the co-director of the $6.4 million Center for Biomedical Research Excellence (COBRE) recently created by the NIH at the University of Delaware.
 
 

Irene McClay Davis, Ph.D., PT

Currently Dr. McClay-Davis has funding from NIH and the Department of Defense totaling  $1.5 million to pursue her research interests.  Dr. Irene McClay-Davis' research is focused on the relationships between lower extremity structure, mechanics and injury and she uses running as a model.

A 5 yr. dual center, prospective and retrospective study funded by the Department of Defense is currently underway under Dr. McClay-Davis' direction.  The focus is the study of the structural and biomechanical factors in the etiology of tibial stress fractures in women runners (figure 1).  Preliminary results of the retrospective portion of the study supports that stress fractures are associated with biomechanical variables associated with increased loading of the lower extremity.

In addition, a 5 yr. study, recently funded by the NIH, has begun to evaluate the short and long term effect of wedged foot orthoses on knee joint osteoarthritis. 
 
 

James C. (Cole) Galloway, Ph.D., PT

Dr. Galloway's research focuses on the neuromotor control of infant behavior.  He is especially interested in how very young infants coordinate spontaneous limb movements such as arm flapping and kicking for purposeful tasks such as reaching for objects (figure 2). Dr. Galloway uses high-speed motion capture, surface EMG, and multijoint equations of motion to address how coordinated motor behavior emerges from the interaction of the nervous system, the body's mechanics, and the environment. In addition to pediatric neurorehabilitation, his work draws from and has implications for developmental psychology, neurophysiology, biomechanics and evolutionary biology.
 

Findings from past projects include: a) Full term and pre term infants control their legs for reaching weeks before they can reach with their arms. b) Controlling the shoulder is less complex vs. the elbow during reaching in adults and possibly in infants. c) Daily movement training can advance reaching skill in infants not yet able to reach. d) Pre term infants appear to display the learning and short-term memory abilities of full term infants. Each of these findings are currently being extended to include infants at high risk for developmental disorders such as cerebral palsy.

Dr. Galloway's laboratory has also collaborated with toy producers in the development of interactive toys for young infants and infants at risk for developmental delay.  Dr. Galloway's lab has been funded by the University of Delaware, the toy industry, and the American Physical Therapy Association.
 
 

Katherine Rudolph, Ph.D., PT

Dr. Rudolph's research focuses on analyses of movement of persons with orthopedic and neurologic injuries with particular interest in assessing treatment efficacy.  Dr. Rudolph is Principal Investigator on a recently funded grant to investigate how ligamentous laxity influences the development of osteoarthritis (OA) in the knee in persons with genu varum (bowed legs) (NIH P20 RR16458-01, $750,000).  The overall goal of this 5-year study is to determine whether anatomic realignment of the knee joint in patients with moderate genu varum deformity allows for changes in muscle strength, knee joint laxity, knee joint instability and  joint position sense that is compatible with halting the progression of knee OA. The implications of this research will impact the development of treatment programs for persons with OA as well as those who are at risk to develop OA.

Dr. Rudolph is also Principal Investigator in a 3-year, NIH funded grant, (NIH R21-HD40956-01; $450,000) and is preparing another to develop rehabilitation devices using magnetorheologic (MR) fluid: fluid that changes its viscosity in response to an applied magnetic field.  In collaboration with Dr. Jian Quao Sun in the Department of Mechanical Engineering and Dr. Binder-Macleod, Dr. Rudolph is developing a low cost, portable, light weight exercise device that could be ultimately be used to strengthen multiple joints of the body.  This variable resistance exercise device (VRED) will incorporate microprocessor technology to allow a therapist to program resistance applied to a patient's muscles in a precisely controlled manner by modifying a very small amount of current from a simple battery.  Prototype development and a pilot study of strengthening efficacy on a sample of patients with quadriceps weakness are included in this project (figure 3).  The other MR fluid rehabilitation device proposed by Dr. Rudolph and Dr. Sun is a variable resistance orthosis (VRO) for use in re training gait in persons with hemiplegia.  The MR fluid will be incorporated into existing knee brace designs such that the resistance to movement in the knee joint during functional activities, including gait, will allow customized resistance for each patient.  In this project the investigators will build a prototype knee VRO with a programmable electronic control system; test the feasibility of brace use with a group of subjects who have hemiparesis resulting from stroke; and determine changes in gait in subjects with hemiparesis while using the VRO.

Dr. Rudolph is Co investigator on a recently funded, 4-year study investigating mechanisms underlying treatment of ACL rupture (NIH R01HD37985-01, $700,000). The overall goal of this work, lead by Principal Investigator Lynn Snyder-Mackler, PT, ScD, is to determine whether effective rehabilitation programs to dynamically stabilize the knee reduce the adaptations that lead to osteoarthritis in a population at great risk for the development of knee OA. Eighty individuals with ACL rupture who are scheduled for surgery will be randomly assigned to a group that receives a form of neuromuscular training called perturbation training, or a standard rehabilitation group.  Subjects will be evaluated before and after surgery using motion analysis and radiography.  Measures of joint motions, forces, and muscle activation, and mathematical models of joint compression, will be used for comparison. The information derived from this study will provide valuable insight into the management of the approximately 100,000 Americans who rupture their ACLs each year and undergo reconstructive surgery. 
 

Finally, Dr. Rudolph is Co-Investigator on the recently funded collaboration between the Departments of Mechanical Engineering and Physical Therapy (NIH R01 HD38582-01A1; $2,500,000 ). The goal of this 5-year project, headed by Thomas Buchanan, Ph.D.,  is to assist patients with hemiparesis, secondary to stroke, to produce improved walking patterns through a combination of functional electrical stimulation (FES) and robotic-assistive training.   The ten-year goal of this work is to develop a portable system to help patients improve their control of coordinated movements. 

John Scholz  Ph.D., PT

The goal of Dr. Scholz's research is to understand motor control processes in healthy individuals and patients who have neurological dysfunction, particularly stroke.  His current work combines mathematical modeling with experiments to determine how the motor abundance available to the motor control system is managed to produce reliable, functional movement.  This work has focused, to date, on the coordination underlying the control of important performance variables, such as the position of the hand along it's path in a reaching task. This work is currently being extended to an analysis of temporal aspects of such movements. Much of this work has been funded by the National Science Foundation (IBN-0078127, $268,408). In addition, Dr. Scholz is a collaborator on an NIH grant awarded to Dr. Mark Latash at Penn State University to study movement synergies ($141,321). Recent work of this laboratory has also focused on the study of the reaching ability of patients with mild to moderate arm dysfunction following a stroke (figure 4).  The goal of this work is to determine how the motor control system of people with stroke is altered compared to healthy subjects and to explore differences in control in right and left brain lesions. 

Related to this work is work funded by the National Institutes of Health, and carried out in collaboration with several other faculty members at the University of Delaware, to develop a system to re-train walking in patients who have suffered a stroke ($3.5 M).
 
 

Ken Seaman, PT, MA

Mr. Seaman directs the department’s MS Clinic. Mr. Seaman has successfully incorporated other therapeutic disciplines into our clinic. The MS Clinic is held monthly on the third floor of McKinly Lab and averages approximately five assessments per session. Evaluations presently being conducted by the myriad of professionals involved include oxygen consumption, gait analysis, cognitive assessment, durable medical equipment, psychological counseling, nutrition as well as occupational and physical therapy evaluations. Disciplines currently involved in the clinic include, physical therapy, optometry, exercise physiology, adaptive/medical equipment specialist, biomechanics, massage therapy, occupational therapist, and nutrition. The Multiple Sclerosis Clinic serves two purposes; to provide educational opportunities for the Department’s Physical Therapy Students in the evaluation and management of someone with a complex neurological disorder, and to provide a much-needed service to those in the community with Multiple Sclerosis. To date the MS Assessment clinic has evaluated nearly 10% of the individuals registered with the Delaware MS Chapter. The MS Assessment Clinic was awarded the Friends of MS Award at the MS Society of Delaware’s Annual Meeting in November 2002

Mr. Seaman has been recognized repeatedly this year for his outstanding volunteer work. The MS Society of Delaware recognized Mr. Seaman as MS Volunteer of the year for which he received a plaque at a ceremony last spring. This summer, Mr. Seaman was nominated as one of  only five Delawarians awarded the prestigious Jefferson Award. The Jefferson Award, named for Thomas Jefferson, was started in 1972 to encourage volunteerism. The awards are presented on the local and national levels. Although Mr. Seaman was not chosen as the individual to represent Delaware at the national Jefferson Award competition in Washington, DC, he was given a gold medallion by Governor Minner at a ceremony held at the duPont Country Club, on April 17th of this year.

 Mr. Seaman, is also being recognized November 21, 2002, in a ceremony at the Grande Ole Opry in Nashville Tennessee, where he will be inducted into the National Multiple Sclerosis Society’s Volunteer Hall of Fame. 
 
 
 

Lynn Snyder-Mackler, ScD, PT,ATC,SCS

Dr. Snyder-Mackler’s research efforts focus on 1) dynamic stability of the knee and the responses of the quadriceps muscle after anterior cruciate ligament (ACL) injury and  2) osteoarthritis and resultant surgical procedures including ACL reconstruction, high tibial osteotomy and total knee arthroplasty. Mechanistic studies of neuromuscular electrical stimulation (NMES) and perturbation training can be used to augment muscle strength and affect function in patients after injury as well as randomized controlled clinical trials of these interventions comprise the majority of Dr. Snyder-Mackler’s research. The research reflects an overarching clinical interest in the effectiveness of therapeutic interventions, particularly NMES and neuromuscular training. Dr. Snyder-Mackler is most interested in the relationships between impairments (e.g. quadriceps strength) and dysfunction (e.g. gait abnormalities) after knee injury, although her laboratory also investigates mechanistic questions that arise as a consequence of the clinical research. Dr. Snyder-Mackler is a clinical scientist and an active clinical practitioner. In addition to reports of research, she also publishes papers that describe clinical practice guidelines derived from the clinical trials.
 

Dr. Snyder-Mackler’s most recent work has proceeded on several levels, first characterization of the quadriceps in patients with anterior cruciate ligament injury, medial knee osteoarthritis and tricompartmental osteoarthritis; second, the relationship between quadriceps impairments and function, and third, controlled clinical trials of interventions. Her laboratory has characterized the quadriceps impairment that occurs after ACL injury by examining strength, fatigue properties, and morphology. She has found that the quadriceps are weaker, more fatigue resistant and displays no consistent morphological alterations. Failure of central activation of the quadriceps does not appear to occur in most individuals after ACL injury. In a large, multicenter trial, Dr. Snyder-Mackler demonstrated that NMES was more effective than volitional quadriceps exercise for restoring quadriceps strength and normal gait after ACL reconstruction. She has demonstrated that joint laxity does not necessarily result in knee instability and dysfunction after ACL injury. Her group studied the small sub-population of ACL deficient patients who can return to all activities without episodes of instability or swelling and without reconstructive surgery (copers) and determined that their movement characteristics are different from patients who do not compensate well (non-copers). A training program of systematic perturbation of support surfaces (perturbation training) was developed based on the identified characteristics and has been tested in a randomized clinical trial and was superior to a traditional program in returning individuals to high level activity after ACL injury. Most recently, she has begun to study some of these same problems in the elderly and those with total knee replacement. This work has already resulted in two papers with Dr. Binder-Macleod. A trial of the use of NMES in elderly patients following total knee replacements is now being undertaken and is funded by a five year 1.2 million dollar grant from the NIH that also includes an imaging component in collaboration with Dr. Krista Vandenbourne at the University of Florida.

Dr. Snyder-Mackler regularly collaborates with colleagues in the Physical Therapy and Mechanical Engineering Departments, and other scientists in the United States and abroad. Her major collaborators are Dr. Katy Rudolph, Dr. Michael Axe and Dr. Tom Buchanan.  Dr. Thomas Buchanan and Dr. Snyder-Mackler have collaborated on two projects and three successful grant applications. The first grant application was the aforementioned study of what makes "copers" and " non-copers” by studying the subjects' kinematics (i.e., gait analysis) and muscle activation patterns (EMGs) during a variety of tasks.  The second is a new approach to in vivo analysis of musculoskeletal dynamics uses Cine-phase contrast (Cine-PQ magnetic resonance imaging (MRI) to image and track the moving knee. Cine-PC MRI, a non-invasive technique, is capable of measuring 3D muscle fiber and skeletal velocity, in vivo, during dynamic tasks. Through integration, 3D musculoskeletal movement can be tracked. A combination of the use of this new technology and conventional MRI, electromyography, and musculoskeletal modeling provide a unique opportunity to elucidate the compensation strategies employed by patients with anterior cruciate ligament (ACL) injuries. The third grant application is to investigate the mechanisms underlying the development of dynamic knee stability after ACL rupture and extends the clinical trials of perturbation training to the non-coper population. 

Dr. Rudolph and Dr. Snyder-Mackler are currently studying the effects of knee realignment on the progression of osteoarthritis as part of a large COBRE center grant on osteoarthritis.  They are also collaborating with Dr. May-Arna Risberg and her team in Oslo, Norway on testing the effects of neuromuscular training after ACL reconstruction in a study funded by the Norwegian Research Council.  Dr. Snyder-Mackler has most recently begun collaboration with Dr. Edward Wojtys at the University of Michigan in testing the effects of neuromuscular training on muscle activity patterns in healthy active subjects in an effort to shed some light on training to prevent traumatic knee ligament injury,

Dr. Snyder-Mackler is currently funded by the National Institutes of Health as a principal investigator on two R0-1’s and the CO-PI on the COBRE project with Dr. Rudolph, for a total of $600,000/yr.