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245
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Introduction
Current institution
Education
August 1986 - December 1989
August 1985 - August 1986
August 1981 - May 1985
Publications
Publications (245)
Context:
Guidelines for various movement assessments often instruct clinicians to conduct testing without a warm-up. Warm-ups are commonly performed to increase heart rate, decrease stiffness, and prepare for sport-specific demands. Since athletes typically complete a warm-up prior to sport participation, evaluating biomechanics in this condition...
University recreation centers offer various sport programs and activities. However, injury surveillance data in this setting is lacking. The purpose of this study was to describe injury frequency for college recreational athletes by year, semester, indoor/outdoor locations, playing surface type, activity, injury type, body region, and body part. 2,...
Low back pain is a frequent injury in golfers which impacts trunk muscle activity patterns. The primary purpose of this study was to bilaterally compare thickness of the external obliques and internal obliques across three positions (supine, golf setup, and swing peak) in 16 adult golfers with a history of low back pain via ultrasound. There were n...
Autonomous exercise within nonspecific low back pain rehabilitation is a necessary tool to treat low back pain. The purpose of this study was to quantify adherence and compliance during two different 6-week home-exercise programs. Forty adults were randomly allocated to a gamified and packet group. Adherence, compliance, and system usability assess...
Purpose:
To measure the change in pain and disability during and after a 6-week gamified delivery of home exercise compared to a take-home packet.
Materials and methods:
A 6-week at-home exercise protocol included participants randomly allocated to a gamified delivery group or packet group. The exercise protocol included the plank, side plank, f...
Objectives
To compare activation ratios of the transverse abdominis (TrA) during an abdominal draw-in maneuver (ADIM) and abdominal obliques during a golf swing, with and without ultrasound biofeedback, and to determine intrarater reliability of these ultrasound thickness measures.
Design
Single-session crossover study.
Setting
Laboratory.
Parti...
Purpose: The purpose of this investigation was to compare the quality of neural drive and recruited quadriceps motor units’ (MU) action potential amplitude (MUAPAMP), and discharge rate (mean firing rate (MFR)) relative to recruitment threshold (RT) between individuals with anterior cruciate ligament reconstruction
(ACLR) and controls.
Methods: Fou...
Background:
Adequate normalization methodology to establish maximum voluntary isometric contraction (MVIC) is needed to compare %MVIC values for core exercise completed until discontinuation. Clinicians can use %MVIC classifications to guide their preventative and rehabilitative exercise interventions.
Objective:
The aim of this study was to com...
The purpose of this study was to compare neuromuscular function in the upper extremity musculature between individuals with glenohumeral labrum repair and uninjured controls. This cross‐sectional study examined 16 individuals with a primary, unilateral glenohumeral labral repair (male/female: 13/3, age: 24.1±5.0 years, time from surgery: 36.7±33.3...
Reliable techniques to assess centrally mediated function in healthy individuals are essential to understand the origins of neuromuscular dysfunction in pathologic populations. This study examined the test–retest reliability of corticospinal excitability in the upper extremity musculature of 21 healthy individuals using transcranial magnetic stimul...
Context:
Arthrogenic muscle inhibition (AMI) is a common neurophysiological response to joint injury. While athletic trainers (ATs) are constantly treating patients with AMI, it is unclear how clinicians are using the available evidence to treat the condition.
Objective:
To investigate ATs' general knowledge, clinical practice, and barriers for...
Context:
Quadriceps activation failure has been observed following various pathological conditions in a knee joint such as knee surgery, pain, effusion in knee, and osteoarthritis also could be aging matter. Those patients are unable to attain maximal quadriceps strength for a long period of time although their quadriceps itself is not damaged. Th...
Impaired corticomotor function arising from altered intracortical and corticospinal pathways are theorized to impede muscle recovery following anterior cruciate ligament (ACL) surgery, yet functional implications of centrally driven adaptations remain unclear. We aimed to assess relationships between quadriceps corticomotor and neuromechanical func...
Context:
Central activation ratio (CAR) is a common outcome measure used to quantify gross neuromuscular function of the quadriceps using the superimposed burst technique, yet this outcome measure has not been validated in the gluteal musculature.
Objective:
To quantify gluteus medius (GMed) and gluteus maximus (GMax) CAR in a healthy population...
Educational institutions sponsoring competitive athletics may use an athletics model, academic model, or medical model for delivery of sports medicine to student-athletes. Four types of legal risk are considered for these 3 models: litigation, contract, regulatory, and structural. The athletics model presents the greatest legal risk to institutions...
Context:
Impaired scapular kinematics is commonly reported in patients with subacromial impingement syndrome (SIS). Various therapeutic interventions designed to improve scapular kinematics and minimize pain and disability have been described in the literature. However, the short- and long-term benefits of these interventions are unclear.
Objecti...
Context:
Patient-reported outcomes (PROs) evaluate how patients describe symptoms as well as level of physical function or quality of life. The Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index is one of the most common PROs used to assess disability in patients with knee osteoarthritis (OA), yet the Single Assessment Numeric...
Context:
Focal ankle-joint cooling (FAJC) has been shown to increase Hoffmann (H) reflex amplitudes of select leg muscles while subjects lie prone, but it is unknown whether the neurophysiological cooling effects persist in standing.
Objective:
To assess the effects of FAJC on H-reflexes of the soleus and fibularis longus during 3 body positions...
Context:
Persistent muscle weakness after anterior cruciate ligament (ACL) reconstruction may be due to underlying activation failure and arthrogenic muscle inhibition (AMI). Knee-joint cryotherapy has been shown to improve quadriceps function transiently in those with AMI, thereby providing an opportunity to improve quadriceps muscle activation a...
Manual therapies, directed to the knee and lumbopelvic region, have demonstrated the ability to improve neuromuscular quadriceps function in individuals with knee pathology. It remains unknown if manual therapies may alter impaired spinal reflex excitability, thus identifying a potential mechanism in which manual therapy may improve neuromuscular f...
Purpose/background:
Physical inactivity is common in patients with knee osteoarthritis (OA) and has been linked to serious comorbidities such as cardiovascular disease, obesity, and diabetes. The purpose of this study was to examine the association between quadriceps strength and self-reported physical activity in patients with radiographically co...
Context:
Analyzing ligament stiffness between males and females at 3 maturational stages across the lifespan may provide insight into whether changes in ligament behavior with aging may contribute to joint laxity.
Objective:
To compare the stiffness of the medial structures of the tibiofemoral joint and the medial collateral ligament to determin...
The virtual reality (VR) therapy described below consists of a series of VR exercises, delivered with low-cost equipment. It replicates the conventional exercise and activity sequence recommended for restoring postural and coordination abnormalities after traumatic brain injuries (TBI). Efficacy was tested in a pilot group of 9 participants with TB...
Context:
Anterior cruciate ligament (ACL) injuries are common in female athletes and are related to poor neuromuscular control. Comprehensive neuromuscular training has been shown to improve biomechanics; however, we do not know which component of neuromuscular training is most responsible for the changes.
Objective:
To assess the efficacy of ei...
Objective
To compare strength and quadriceps muscle activation in anterior cruciate ligament-deficient patients who underwent a two-week rehabilitation exercise program using TENS or cryotherapy.
Design
Randomized, controlled study.
Setting
Clinical research laboratory.
Subjects
Thirty patients: 20 males, 10 females, 31.6 (13.0) years, 172.8 (10...
Postural control as assessed via time-to-boundary (TTB) measures has been shown to be impaired in those with chronic ankle instability (CAI). Foot orthotics have been shown to improve postural control, although it is not clear if this is via mechanical or sensorimotor mechanisms.
To assess the effect of textured shoe inserts that provide no mechani...
Randomized clinical trial.
To determine whether manipulation of the proximal or distal tibiofibular joint would change ankle dorsiflexion range of motion and functional outcomes over a 3-week period in individuals with chronic ankle instability.
Altered joint arthrokinematics may play a role in chronic ankle instability dysfunction. Joint mobilizat...
To determine if motor evoked potentials (MEPs), postconcussion signs and symptoms, and neurocognitive functions follow a similar recovery pattern after concussion.
Nine collegiate athletes with acute concussion (>24 hours after injury) participated in this retrospective time series design. Transcranial magnetic stimulation was applied over the moto...
Quadriceps weakness and inhibition are impairments associated with patellofemoral pain syndrome (PFPS). Lumbopelvic joint manipulation has been shown to improve quadriceps force output and inhibition, but the duration of the effect is unknown.
To determine whether quadriceps strength and activation are increased and maintained for 1 hour after high...
Fatigue of the gluteus medius (GMed) muscle might be associated with decreases in postural control due to insufficient pelvic stabilization. Men and women might have different muscular recruitment patterns in response to GMed fatigue.
To compare postural control and quality of movement between men and women after a fatiguing hip-abduction exercise....
Knee braces and neoprene sleeves are commonly worn by people with anterior cruciate ligament reconstructions (ACLRs) during athletic activity. How knee braces and sleeves affect muscle activation in people with ACLRs is unclear.
To determine the effects of knee braces and neoprene knee sleeves on the quadriceps central activation ratio (CAR) before...
The ability to accurately estimate quadriceps voluntary activation is an important tool for assessing neuromuscular function after a variety of knee injuries. Different techniques have been used to assess quadriceps volitional activation, including various stimulating electrode types and electrode configurations, yet the optimal electrode types and...
Dosage for the galvanic stimulation for iontophoresis varies. Clinicians manipulate the duration or the amplitude of the current, but it is not known which is more effective. We compared the anesthetic effect of lidocaine HCL (2%) by manipulating the current parameters on 21 healthy volunteers (age: 21.2 ± 4.2, height 170.7 ± 10.2 cm, mass 82.1 ± 1...
Weight-bearing (WB) and non-weight-bearing (NWB) exercises are commonly used in rehabilitation programs for patients with anterior knee pain (AKP).
To determine the immediate effects of isolated WB or NWB knee-extension exercises on quadriceps torque output and activation in individuals with AKP.
A single-blind randomized controlled trial.
Laborato...
Individuals with low back pain (LBP) are thought to benefit from interventions that improve motor control of the lumbopelvic region. It is unknown if therapeutic exercise can acutely facilitate activation of lateral abdominal musculature.
To investigate the ability of 2 types of bridging-exercise progressions to facilitate lateral abdominal muscles...
Traumatic brain injury (TBI) disrupts the central and executive mechanisms of arm(s) and postural (trunk and legs) coordination. To address these issues, we developed a 3D immersive videogame--Octopus. The game was developed using the basic principles of videogame design and previous experience of using videogames for rehabilitation of patients wit...
This randomized, controlled, laboratory study was designed to examine the effect of cold water immersion (CWI) as a recovery modality on repeat performance on the yo-yo intermittent recovery test (YIRT), a widely accepted tool for the evaluation of physical performance in soccer, separated by 48 hours. Twenty-two healthy Division I collegiate socce...
Anterior cruciate ligament (ACL) reconstructions are common, especially in young, active people. The lower extremity neuromuscular adaptations seen after aerobic exercise provide information about how previously injured patients perform and highlight deficits and, hence, areas for focused treatment. Little information is available about neuromuscul...
Many professionals work closely with physicians and nurses to provide healthcare that is safe, patient-centered, efficient, equitable, timely, and effective. These professionals represent many and varied allied health disciplines. Each allied health professional is ethically accountable for bringing a theoretically-sound and evidence-based approach...
This paper describes the effects of short-term practice with the custom-made 3D immersive videogame Octopus on arm-postural coordination in patients with traumatic brain injury (TBI). Unlike many other custom-designed virtual environments, Octopus includes an actual gaming component with a system of multiple rewards, making the game challenging, co...
Throwing is a complex motion that involves the entire body and often puts an inordinate amount of stress on the shoulder and the arm. Warm-up prepares the body for work and can enhance performance. Sling-based exercise (SE) has been theorized to activate muscles, particularly the stabilizers, in a manner beneficial for preactivity warm-up, yet this...
Objective: To compare the effect of acute lateral ankle sprain on the motor-neuron pool excitability (MNPE) of injured leg muscles with that of uninjured contralateral leg muscles and the leg muscles of healthy controls.
Patients or Other Participants: Ten individuals with acute ankle sprains (6 females, 4 males; age = 19.2 ± 3.8 years, height = 16...
Neuromuscular deficits in leg muscles that are associated with arthrogenic muscle inhibition have been reported in people with chronic ankle instability, yet whether these neuromuscular alterations are present in individuals with acute sprains is unknown.
To compare the effect of acute lateral ankle sprain on the motor-neuron pool excitability (MNP...
Authors request their Abstract not to be published.
Individuals with low back pain (LBP) have been shown to demonstrate decreased quadriceps activation following lumbar paraspinal fatigue. The response of other lower extremity muscles is unknown. The purpose of this study was to determine changes in motoneuron pool excitability of the vastus medialis, fibularis longus, and soleus following lumbar pa...
The objective of this study was to assess the magnitude of quadriceps activation deficits in the involved extremity and contralateral extremity of patients with knee joint osteoarthritis (OA), as well as matched controls. An exhaustive search of the literature was performed using Web of Science between 1970 and February 24, 2010, using the search t...
More than 1.6 million sport-related concussions occur every year in the United States, affecting greater than 5% of all high school athletes who participate in contact sports. As more females participate in sports, understanding possible differences in concussion symptoms between sexes becomes more important.
To compare symptoms, symptom resolution...
Blinded, randomized controlled trial.
To determine if the combination of transcutaneous electrical nerve stimulation (TENS) set to a sensory level and therapeutic exercise would be more effective than the combination of placebo TENS and therapeutic exercises or therapeutic exercises only to increase quadriceps activation in individuals with tibiofe...
Objective: To determine whether sensory transcutaneous electrical nerve stimulation (TENS) augmented with therapeutic exercise and worn for daily activities for four weeks would alter peak gait kinetics and kinematics, compared with placebo electrical stimulation and exercise, and exercise only.
Design: Randomized controlled trial.
Setting: Motion...
Motor evoked potentials (MEPs) induced through transcranial magnetic stimulation (TMS) are susceptible to several sources of variability including gender, hand dominance, and upper extremity length. Conflicting evidence on the relationship between MEPs and subject characteristics has been reported.
The purposes of this study were to determine if ME...
Quadriceps-activation deficits have been reported after meniscectomy. Transcranial magnetic stimulation (TMS) in conjunction with maximal contractions affects quadriceps activation in patients after meniscectomy.
To determine the effect of single-pulsed TMS on quadriceps central activation ratio (CAR) in patients after meniscectomy.
Randomized cont...
Unlabelled:
A relationship exists between muscles of the lumbar spine and those of the lower extremity where the quadriceps become more inhibited after lumbar paraspinal. The purpose of this experiment was to compare surface electromyography (sEMG) total frequency content after lumbar paraspinal fatiguing exercise.
Scope:
50 subjects performed f...
A relationship between the muscles that stabilize the lumbar spine and the lower extremity exists that may result in neuromuscular and biomechanical changes during prolonged aerobic exercise in those with low back pain.
Twenty recreationally active adults with healthy lower extremity joints, 7 with recurring episodes of low back pain performed a st...
To determine the relationship between quadriceps central activation ratios (CARs) derived from a percutaneous electrical stimulation (CAR(SIB)) and a transcranial magnetic stimulation (CAR(TMS)) in healthy participants.
Nineteen healthy participants (5 men, 14 women, 23.7 ± 4.8 yrs, 66.8 ± 10.0 kg, and 170.1 ± 7.0 cm) qualified for this descriptive...
Quadriceps activation failure is common in patients with tibiofemoral osteoarthritis (TFOA) and has been reported to occur bilaterally following acute and chronic knee injuries. Sensory transcutaneous electrical stimulation (TENS) applied to the knee has increased ipsilateral quadriceps activation, yet it remains unknown if repeated sensory TENS tr...
Recommendations on the positioning of the tibiofemoral joint during a valgus stress test to optimize isolation of the medial collateral ligament (MCL) from other medial joint structures vary in the literature. If a specific amount of flexion could be identified as optimally isolating the MCL, teaching and using the technique would be more consisten...
Assessment of concussion is primarily based on self-reported symptoms, neurological examination and neuropsychological testing. The neurophysiologic sequelae and the integrity of the corticomotor pathways could be obtained by evaluating motor evoked potentials (MEPs).
To compare MEPs obtained through transcranial magnetic stimulation (TMS) in acute...
Rib injuries are common in collegiate rowing. The purpose of this case report is to provide insight into examination, evaluation, and treatment of persistent costochondritis in an elite athlete as well as propose an explanation for chronic dysfunction. The case involved a 21 year old female collegiate rower with multiple episodes of costochondritis...
Anecdotal evidence suggests that athletes who play sports requiring explosive activities are more susceptible to hamstring strain. No published studies exist that compare the incidence of hamstring strain between genders or sports. Thus, the purpose of this study is to compare those rates between genders and sports during the 2004-2007 National Col...
Though clinical observations and laboratory data provide some support for the neuromuscular imbalance theory of the genesis of exercise-associated muscle cramps, no direct evidence has been published. The purpose of this study was to determine the effect of local muscle fatigue on the threshold frequency of an electrically induced muscle cramp. To...
Motoneuron-pool facilitation after cryotherapy may be mediated by stimulation of thermoreceptors surrounding a joint. It is unknown whether menthol counterirritants, which also stimulate thermoreceptors, have the same effect on motoneuron-pool excitability (MNPE).
To compare quadriceps MNPE after a menthol-counterirritant application to the anterio...
Arthrogenic muscle inhibition is an important underlying factor in persistent quadriceps muscle weakness after knee injury or surgery.
To determine the magnitude and prevalence of volitional quadriceps activation deficits after knee injury.
Web of Science database.
Eligible studies involved human participants and measured quadriceps activation usin...
After total knee arthroplasty, quadriceps femoris muscle strength is an important determinant of physical function. Quadriceps weakness is often present in the osteoarthritic limb and worsens after total knee arthroplasty. Although some quadriceps strength is regained, it may take more than 2 years to achieve preoperative levels, and it is unclear...
A relationship exists between lumbar paraspinal muscle fatigue and quadriceps muscle activation. The objective of this study was to determine whether hip and knee joint moments during jogging changed following paraspinal fatiguing exercise. Fifty total subjects (25 with self-reported history of low back pain) performed fatiguing, isometric lumbar e...
Isolated lumbar paraspinal muscle fatigue causes lower extremity and postural control deficits.
To describe the change in body position during gait after fatiguing lumbar extension exercises in persons with recurrent episodes of low back pain compared with healthy controls.
Case-control study.
Motion analysis laboratory.
Twenty-five recreationally...
Kinematic patterns during gait have not been extensively studied in relation to chronic ankle instability (CAI).
To determine whether individuals with CAI demonstrate altered ankle kinematics and shank-rear-foot coupling compared with controls during walking and jogging.
Case control.
Motion-analysis laboratory.
7 participants (3 men, 4 women) suff...
The stretching window is a theoretical concept that refers to the period of maximum tissue temperature increase during and immediately following ultrasound treatment. This study was conducted to determine if an optimal time period exists for combining ultrasonic heat and stretching to obtain maximum joint range of motion; essentially, evaluate the...
Objective: To examine the effects of a four-week balance training programme on ankle kinematics during walking and jogging in those with chronic ankle instability. A secondary objective was to evaluate the effect of balance training on the mechanical properties of the lateral ligaments in those with chronic ankle instability. Design: Randomized con...
The objective of this study was to evaluate the effects of a 20-min focal knee joint cooling intervention on quadriceps central activation ratio (CAR) in healthy volunteers. A counterbalanced, cross-over study assessed the effects of a focal joint cooling intervention compared with a control condition 3-14 days apart. Eleven healthy volunteers (6 m...
To determine whether transcutaneous electrical nerve stimulation (TENS) and focal knee joint cooling will affect the quadriceps central activation ratio (CAR) in patients with tibiofemoral osteoarthritis.
Thirty-three participants with diagnosed tibiofemoral osteoarthritis were randomly allocated to the 45-min TENS treatment (six males and four fem...
Range of motion (ROM) exercises are accepted as being an essential part of post-operative knee rehabilitation but there is little research to support this treatment. Our purpose was to determine whether a specific early, active ROM intervention using a bicycle ergometer equipped with an adjustable pedal arm offered measurable benefit to post-operat...
The purpose of this randomized controlled trial was to determine the effect of a 4-wk balance training program on static and dynamic postural control and self-reported functional outcomes in those with chronic ankle instability (CAI).
Thirty-one young adults with self-reported CAI were randomly assigned to an intervention group (six males and 10 fe...
