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Lynn Snyder-mackler - One of the best experts on this subject based on the ideXlab platform.
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Response of male and female subjects after total knee arthroplasty to repeated neuromuscular electrical stimulation of the Quadriceps Femoris Muscle.
American Journal of Physical Medicine & Rehabilitation, 2010Co-Authors: Yocheved Laufer, Lynn Snyder-macklerAbstract:ABSTRACTLaufer Y, Snyder-Mackler L: Response of male and female subjects after total knee arthroplasty to repeated neuromuscular electrical stimulation of the Quadriceps Femoris Muscle.Objectives:To examine responses to repeated neuromuscular electrical stimulation of the Quadriceps Femoris Muscle i
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Voluntary activation and decreased force production of the Quadriceps Femoris Muscle after total knee arthroplasty
Physical therapy, 2003Co-Authors: Ryan L. Mizner, Jennifer E. Stevens, Lynn Snyder-macklerAbstract:Background and Purpose. Quadriceps Femoris Muscle weakness as manifested by a decrease in force-generating capability is a persistent problem after total knee arthroplasty (TKA). The authors hypothesized that (1) patients with a TKA would have decreased Quadriceps Femoris Muscle performance (weakness) and impaired volitional activation when compared with a group of older adults without knee pathology, (2) pain and age would account for a large portion of the variability in volitional activation after surgery, and (3) volitional activation in the TKA group would account for a large portion of the variability in force production. Subjects. Comparison subjects were 52 volunteers (mean age=72.2 years, SD=5.34, range=64–85). The TKA group comprised 52 patients (mean age=64.9 years, SD=7.72, range=49–78) with a diagnosis of osteoarthritis who had undergone a tricompartmental, cemented TKA. Methods. Knee extension force was measured using a burst superimposition technique, where a supramaximal burst of electrical stimulation was superimposed on a maximal voluntary isometric contraction (MVIC). The amount of failure of volitional activation is determined by the amount of electrical augmentation of force beyond a person's MVIC at the instant of the application of the electrical burst. Results. The average normalized knee extension force of the TKA group was 64% lower than that of the comparison group. The average volitional activation deficit in the TKA group (26%) was 4 times as great as the comparison group's deficit (6%). Age did not correlate with Quadriceps Femoris Muscle activation, and knee pain explained only a small portion of the variance in knee extension force ( r 2=.17). Volitional activation was highly correlated with knee extension force production ( r 2=.65). Discussion and Conclusion. Considerable Quadriceps Femoris Muscle inhibition after surgery has several implications for recovery. Rehabilitation programs that focus on volitional exercise alone are unlikely to overcome this pronounced failure of activation. Early interventions focused at improving Quadriceps Femoris Muscle voluntary activation may improve efforts to restore Muscle force.
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The Use of Electrical Stimulation to Increase Quadriceps Femoris Muscle Force in an Elderly Patient Following a Total Knee Arthroplasty
Physical therapy, 2001Co-Authors: Michael D. Lewek, Jennifer E. Stevens, Lynn Snyder-macklerAbstract:Background and Purpose. Persistent residual Quadriceps Femoris Muscle force deficits after total knee arthroplasty (TKA) are commonly reported and can prevent patients from returning quickly and fully to functional activities. Neuromuscular electrical stimulation offers a potentially more effective means of increasing Muscle force than current rehabilitation protocols. Case Description. The patient was a 66-year-old man. Neuromuscular electrical stimulation for increasing Quadriceps Femoris Muscle force was initiated 3 weeks after TKA for 11 sessions to supplement stretching exercises and a high-intensity volitional strengthening program. Outcome. The patient's isometric Quadriceps Femoris Muscle force increased from 50% (involved/uninvolved) at 3 weeks after surgery to 86% at 8 weeks after surgery. A concurrent increase in his uninvolved Quadriceps Femoris Muscle force concealed the patient's true increase in his involved Quadriceps Femoris Muscle force in a side-to-side comparison. The patient's final involved Quadriceps Femoris Muscle force (10 weeks after surgery) was 93% of the initial uninvolved Quadriceps Femoris Muscle force. Discussion. Our patient was able to return to independent activities of daily living and recreational activities, with force gains that surpassed those reported in the literature.
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Failure of voluntary activation of the Quadriceps Femoris Muscle after patellar contusion.
The Journal of orthopaedic and sports physical therapy, 2000Co-Authors: Tara Jo Manal, Lynn Snyder-macklerAbstract:Study Design Descriptive study of phenomenon. Objectives To determine the extent of failure of voluntary activation of the Quadriceps Femoris Muscle in patients early after patellar contusion. Background Pain and effusion are related to the presence of Quadriceps inhibition. We hypothesized that patients with patellar contusions would be unable to fully recruit their Quadriceps Muscles and that the activation deficit would be associated with self-report measures of function. Methods and Measures Sixteen patients who had sustained a unilateral patellar contusion fewer than 4 months prior to testing participated in the study (7 men, 9 women; mean age = 30.0 ± 11.6). Subjects completed a self-report questionnaire to assess knee function and performed an isometric burst superimposition test on the involved and uninvolved Quadriceps at 60° of knee flexion. The subjects were assigned to 2 groups according to the presence (n = 5) or absence (n = 11) of Quadriceps inhibition. Results Sixty-nine percent of the sub...
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Reflex inhibition of the Quadriceps Femoris Muscle after injury or reconstruction of the anterior cruciate ligament.
The Journal of bone and joint surgery. American volume, 1994Co-Authors: Lynn Snyder-mackler, Patrick R. Williams, P F De Luca, Marty Eastlack, Arthur R. BartolozziAbstract:A burst-superimposition technique was used to assess the strength of the Quadriceps Femoris Muscle in three groups of patients. Group 1 comprised twenty patients who had had a torn anterior cruciate ligament of the knee and had a reconstruction of the ligament one to six months after the injury. Group 2 comprised twelve patients who had had a torn anterior cruciate ligament for an average of three months (a subacute tear). Group 3 comprised eight patients who had had a torn anterior cruciate ligament for an average of two years (a chronic tear). The patients in Groups 2 and 3 had not had an operation for the torn ligament. The patients in Groups 1 and 3 had no evidence of failure of activation of the involved Quadriceps, but nine of the twelve patients in Group 2 had reflex inhibition of contraction of the Muscle.
Nicolas Place - One of the best experts on this subject based on the ideXlab platform.
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a new paradigm of neuromuscular electrical stimulation for the Quadriceps Femoris Muscle
European Journal of Applied Physiology, 2014Co-Authors: Nicola A. Maffiuletti, Marco Alessandro Minetto, Isabelle Vivodtzev, Nicolas PlaceAbstract:Purpose Neuromuscular electrical stimulation (NMES) with large electrodes and multiple current pathways (m-NMES) has recently been proposed as a valid alternative to conventional NMES (c-NMES) for Quadriceps Muscle (re)training. The main aim of this study was to compare discomfort, evoked force and fatigue between m-NMES and c-NMES of the Quadriceps Femoris Muscle in healthy subjects.
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A new paradigm of neuromuscular electrical stimulation for the Quadriceps Femoris Muscle
European journal of applied physiology, 2014Co-Authors: Nicola A. Maffiuletti, Marco Alessandro Minetto, Isabelle Vivodtzev, Nicolas PlaceAbstract:Neuromuscular electrical stimulation (NMES) with large electrodes and multiple current pathways (m-NMES) has recently been proposed as a valid alternative to conventional NMES (c-NMES) for Quadriceps Muscle (re)training. The main aim of this study was to compare discomfort, evoked force and fatigue between m-NMES and c-NMES of the Quadriceps Femoris Muscle in healthy subjects. Ten healthy subjects completed two experimental sessions (c-NMES and m-NMES), that were randomly presented in a cross-over design. Maximal electrically evoked force at pain threshold, self-reported discomfort at different levels of evoked force, and fatigue-induced force declines during and following a series of 20 NMES contractions were compared between c-NMES and m-NMES. m-NMES resulted in greater evoked force (P
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a new paradigm of neuromuscular electrical stimulation for the Quadriceps Femoris Muscle
European Journal of Applied Physiology, 2014Co-Authors: Nicola A. Maffiuletti, Marco Alessandro Minetto, Isabelle Vivodtzev, Nicolas PlaceAbstract:Neuromuscular electrical stimulation (NMES) with large electrodes and multiple current pathways (m-NMES) has recently been proposed as a valid alternative to conventional NMES (c-NMES) for Quadriceps Muscle (re)training. The main aim of this study was to compare discomfort, evoked force and fatigue between m-NMES and c-NMES of the Quadriceps Femoris Muscle in healthy subjects. Ten healthy subjects completed two experimental sessions (c-NMES and m-NMES), that were randomly presented in a cross-over design. Maximal electrically evoked force at pain threshold, self-reported discomfort at different levels of evoked force, and fatigue-induced force declines during and following a series of 20 NMES contractions were compared between c-NMES and m-NMES. m-NMES resulted in greater evoked force (P < 0.05) and lower discomfort in comparison to c-NMES (P < 0.05–0.001), but fatigue time course and magnitude did not differ between the two conditions. The use of Quadriceps m-NMES appears legitimate for (re)training purposes because it generated stronger contractions and was less discomfortable than c-NMES (due to multiple current pathways and/or lower current density with larger electrodes).
Yocheved Laufer - One of the best experts on this subject based on the ideXlab platform.
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Quadriceps Femoris Muscle fatigue in patients with knee osteoarthritis.
Clinical interventions in aging, 2013Co-Authors: Michal Elboim-gabyzon, Nimrod Rozen, Yocheved LauferAbstract:The purpose of this study was to characterize Quadriceps Femoris Muscle fatigue of both lower extremities in patients with knee osteoarthritis (OA). Sixty-two subjects (mean age 68.2 years, standard deviation (SD) ± 7.9 years) with knee OA participated in the study. Sig- nificantly higher knee pain was reported in the involved knee than in the contralateral knee, as determined by a visual analog scale. Significant differences were demonstrated between the lower extremities in terms of maximal voluntary isometric contraction, in favor of the less involved leg (P = 0.0001). In contrast, the degree of fatigue of the Quadriceps Femoris Muscle, as measured by the decrement in force production following ten repeated contractions, was significantly higher in the contralateral leg (P = 0.0002). Furthermore, normalization of the fatigue results to the first contraction yielded a similar result ( P , 0.0001). Similar results were noted when analysis was performed separately for subjects whose involvement was unilateral or bilateral. The results indicate that, irrespective of the initial strength of contraction, the rate of Muscle fatigue in the contralateral leg is significantly higher than in the involved leg. Hypotheses for these unexpected results are suggested. Rehabilitation of patients with knee OA should focus on increasing Quadriceps Muscle strength and endurance for both lower extremities.
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Response of male and female subjects after total knee arthroplasty to repeated neuromuscular electrical stimulation of the Quadriceps Femoris Muscle.
American Journal of Physical Medicine & Rehabilitation, 2010Co-Authors: Yocheved Laufer, Lynn Snyder-macklerAbstract:ABSTRACTLaufer Y, Snyder-Mackler L: Response of male and female subjects after total knee arthroplasty to repeated neuromuscular electrical stimulation of the Quadriceps Femoris Muscle.Objectives:To examine responses to repeated neuromuscular electrical stimulation of the Quadriceps Femoris Muscle i
Friedemann Awiszus - One of the best experts on this subject based on the ideXlab platform.
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Strength and Voluntary Activation of Quadriceps Femoris Muscle in Total Knee Arthroplasty with Midvastus and Subvastus Approaches
The Journal of arthroplasty, 2007Co-Authors: Alexander Berth, Dietmar Urbach, Wolfram Neumann, Friedemann AwiszusAbstract:To determine and compare the influence of 2 different approaches on Quadriceps Femoris Muscle function in total knee arthroplasty (TKA), 20 patients (14 women, 6 men) with bilateral knee osteoarthritis underwent a 1-stage bilateral TKA. Surgical approaches (subvastus, midvastus) were performed by a random selection. Measurements of Quadriceps voluntary activation and maximal voluntary contraction were estimated by a twitch interpolation technique before, 3 and 6 months after TKA. Knee pain was quantified by the Lewis Score. There was no difference between the 2 approaches at 3 and 6 months after TKA with regard to maximal voluntary contraction (P = 0.84, F = 0.041) and voluntary activation (P = .863, F = 0.031). In the subvastus group was a significantly higher knee pain until 6 months after surgery (P = .02). The subvastus approach for TKA does not provide any advantages compared with the midvastus approach with respect to the Quadriceps Femoris Muscle strength in the early postoperative period. Furthermore, the subvastus approach caused significantly more pain postoperatively.
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stimulus strength related effect of transcranial magnetic stimulation on maximal voluntary contraction force of human Quadriceps Femoris Muscle
Experimental Brain Research, 2002Co-Authors: Dietmar Urbach, Friedemann AwiszusAbstract:It is well accepted that transcranial magnetic stimulation (TMS) can modulate motor cortex excitability long after application. Furthermore, a positive TMS effect on the ability to perform a maximal voluntary contraction (MVC) of the Quadriceps Femoris Muscle has been described. However, stimulus strength dependence and duration of this effect are currently unknown. In the present study these parameters of the TMS-induced MVC enhancement were investigated in seven healthy subjects. Initially, three repetitive transcranial magnetic stimuli of varying stimulus strength were applied every 4 s either during MVC or relaxation. Thereafter, MVC and the ability to activate the Quadriceps Muscle voluntarily (voluntary activation) were determined using a sensitive twitch interpolation technique. In a second experiment we investigated the effect of three transcranial magnetic stimuli applied either during MVC or during relaxation on MVC over a time period of 30 min. There was a small but significant and stimulus strength related positive effect of TMS on MVC. The effect of TMS on voluntary activation was not significant. TMS had to be given during MVC to be effective and the positive effect of TMS when applied during MVC was still present after 30 min. These results indicate that TMS acts differently on the motor cortex depending on its activation status. TMS might have potential therapeutic applications in diseases associated with diminished cortical motor drive and subsequent Muscle weakness.
Nicola A. Maffiuletti - One of the best experts on this subject based on the ideXlab platform.
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a new paradigm of neuromuscular electrical stimulation for the Quadriceps Femoris Muscle
European Journal of Applied Physiology, 2014Co-Authors: Nicola A. Maffiuletti, Marco Alessandro Minetto, Isabelle Vivodtzev, Nicolas PlaceAbstract:Purpose Neuromuscular electrical stimulation (NMES) with large electrodes and multiple current pathways (m-NMES) has recently been proposed as a valid alternative to conventional NMES (c-NMES) for Quadriceps Muscle (re)training. The main aim of this study was to compare discomfort, evoked force and fatigue between m-NMES and c-NMES of the Quadriceps Femoris Muscle in healthy subjects.
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A new paradigm of neuromuscular electrical stimulation for the Quadriceps Femoris Muscle
European journal of applied physiology, 2014Co-Authors: Nicola A. Maffiuletti, Marco Alessandro Minetto, Isabelle Vivodtzev, Nicolas PlaceAbstract:Neuromuscular electrical stimulation (NMES) with large electrodes and multiple current pathways (m-NMES) has recently been proposed as a valid alternative to conventional NMES (c-NMES) for Quadriceps Muscle (re)training. The main aim of this study was to compare discomfort, evoked force and fatigue between m-NMES and c-NMES of the Quadriceps Femoris Muscle in healthy subjects. Ten healthy subjects completed two experimental sessions (c-NMES and m-NMES), that were randomly presented in a cross-over design. Maximal electrically evoked force at pain threshold, self-reported discomfort at different levels of evoked force, and fatigue-induced force declines during and following a series of 20 NMES contractions were compared between c-NMES and m-NMES. m-NMES resulted in greater evoked force (P
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a new paradigm of neuromuscular electrical stimulation for the Quadriceps Femoris Muscle
European Journal of Applied Physiology, 2014Co-Authors: Nicola A. Maffiuletti, Marco Alessandro Minetto, Isabelle Vivodtzev, Nicolas PlaceAbstract:Neuromuscular electrical stimulation (NMES) with large electrodes and multiple current pathways (m-NMES) has recently been proposed as a valid alternative to conventional NMES (c-NMES) for Quadriceps Muscle (re)training. The main aim of this study was to compare discomfort, evoked force and fatigue between m-NMES and c-NMES of the Quadriceps Femoris Muscle in healthy subjects. Ten healthy subjects completed two experimental sessions (c-NMES and m-NMES), that were randomly presented in a cross-over design. Maximal electrically evoked force at pain threshold, self-reported discomfort at different levels of evoked force, and fatigue-induced force declines during and following a series of 20 NMES contractions were compared between c-NMES and m-NMES. m-NMES resulted in greater evoked force (P < 0.05) and lower discomfort in comparison to c-NMES (P < 0.05–0.001), but fatigue time course and magnitude did not differ between the two conditions. The use of Quadriceps m-NMES appears legitimate for (re)training purposes because it generated stronger contractions and was less discomfortable than c-NMES (due to multiple current pathways and/or lower current density with larger electrodes).
