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Fábio Mícolis De Azevedo - One of the best experts on this subject based on the ideXlab platform.
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Patellar Tendon Reflex and Vastus Medialis Hoffmann Reflex Are Down Regulated and Correlated in Women With Patellofemoral Pain
Archives of physical medicine and rehabilitation, 2018Co-Authors: Marcella Ferraz Pazzinatto, Danilo De Oliveira Silva, Fernando Henrique Magalhães, Evangelos Pappas, Amanda Schenatto Ferreira, Marina Cabral Waiteman, Fábio Mícolis De AzevedoAbstract:Abstract Objectives The aims of this study were threefold: (1) to compare the amplitude of patellar tendon Reflex (T-Reflex) between women with patellofemoral pain (PFP) and pain-free controls; (2) to compare the amplitude of vastus medialis Hoffmann Reflex (VM H-Reflex) between women with PFP and pain-free controls; (3) to investigate the association between the amplitude of patellar T-Reflex and VM H-Reflex in women with PFP and pain-free controls. Design Cross-sectional observational study. Setting Laboratory of biomechanics and motor control. Participants Thirty women with PFP and 30 pain-free women aged 18 to 35 years (N=60). Main Outcome Measures Peak-to-peak amplitudes of maximal VM H-Reflex (elicited via electrical stimulation on the femoral nerve) and patellar T-Reflex (elicited via mechanical percussion on the patellar tendon) were estimated. Results Women with PFP had significant lower amplitude of patellar T-Reflex (mean difference=0.086; 95% confidence interval=0.020 to 0.151; P=.010; moderate effect) and VM H-Reflex (mean difference=0.150; 95% confidence interval =0.073 to 0.227; P Conclusions As the T-Reflex is easier to perform than H-Reflex assessments in a clinical setting, it represents a feasible option to assess the impaired excitability of the stretch Reflex pathway associated with PFP.
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Vastus Medialis Hoffmann Reflex Excitability Is Associated With Pain Level, Self-Reported Function, and Chronicity in Women With Patellofemoral Pain
Archives of physical medicine and rehabilitation, 2016Co-Authors: Danilo De Oliveira Silva, Fernando Henrique Magalhães, Nathálie Clara Faria, Deisi Ferrari, Marcella Ferraz Pazzinatto, Evangelos Pappas, Fábio Mícolis De AzevedoAbstract:Abstract Objective To determine the association between the amplitude of vastus medialis (VM) Hoffmann Reflex (H-Reflex) and pain level, self-reported physical function, and chronicity of pain in women with patellofemoral pain (PFP). Design Cross-sectional study. Setting Laboratory of biomechanics and motor control. Participants Women diagnosed with PFP (N=15) aged 18 to 35 years. Interventions Not applicable. Main Outcome Measures Data on worst pain level during the previous month, self-reported physical function, and symptom duration (chronicity) were collected from the participants. Maximum evoked responses were obtained by electrical stimulation applied to the femoral nerve and peak-to-peak amplitudes of normalized maximal H-Reflexes (maximal Hoffmann Reflex/maximal motor wave ratios) of the VM were calculated. A Pearson product-moment correlation matrix ( r ) was used to explore the relations between the amplitude of VM H-Reflex and worst pain during the previous month, self-reported function, and chronicity of pain. Results Strong negative correlations were found between the amplitude of VM H-Reflex and worst pain in the previous month ( r =−.71; P =.003) and chronicity ( r =−.74; P =.001). A strong positive correlation was found between the amplitude of VM H-Reflex and self-reported physical function ( r =.62; P =.012). Conclusions The strong and significant relations reported in this study suggest that women with PFP showing greater VM H-Reflex excitability tend to have lower pain, better physical function, and more recent symptoms. Therefore, rehabilitation strategies designed to increase the excitability of the monosynaptic stretch Reflex should be considered in the treatment of women with PFP if their effectiveness is demonstrated in future studies.
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Lower Amplitude of the Hoffmann Reflex in Women With Patellofemoral Pain: Thinking Beyond Proximal, Local, and Distal Factors
Archives of physical medicine and rehabilitation, 2016Co-Authors: Danilo De Oliveira Silva, Fernando Henrique Magalhães, Nathálie Clara Faria, Deisi Ferrari, Marcella Ferraz Pazzinatto, Evangelos Pappas, Fábio Mícolis De AzevedoAbstract:Abstract Objectives To investigate whether vastus medialis (VM) Hoffmann Reflexes (H-Reflexes) differ on the basis of the presence or absence of patellofemoral pain (PFP) and to assess the capability of VM H-Reflex measurements in accurately discriminating between women with and without PFP. Design Cross-sectional study. Setting Laboratory of biomechanics and motor control. Participants Women (N=30) aged 18 to 35 years were recruited, consisting of 2 groups: women with PFP (n=15) and asymptomatic controls (n=15). Interventions Not applicable. Main Outcome Measures Maximum evoked responses were obtained by electrical stimulation applied to the femoral nerve, and peak-to-peak amplitudes of maximal Hoffmann Reflex (Hmax) and maximal motor wave (Mmax) ratios were calculated. Independent samples t tests were performed to identify differences between groups, and a receiver operating characteristic curve was constructed to assess the discriminatory capability of VM H-Reflex measurements. Results VM Hmax/Mmax ratios were significantly lower in participants with PFP than in pain-free participants ( P =.007). In addition, the VM Hmax/Mmax ratios presented large and balanced discriminatory capability values (sensitivity, 73%; specificity, 67%). Conclusions This study is the first to show that VM H-Reflexes are lower in women with PFP than in asymptomatic controls. Therefore, increasing the excitation of the spinal cord in PFP participants may be essential to maintaining the gains acquired during the rehabilitation programs.
Thomas E Klootwyk - One of the best experts on this subject based on the ideXlab platform.
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cryotherapy and transcutaneous electric neuromuscular stimulation decrease arthrogenic muscle inhibition of the vastus medialis after knee joint effusion
Journal of Athletic Training, 2002Co-Authors: J T Hopkins, Christopher D Ingersoll, Jeffrey E Edwards, Thomas E KlootwykAbstract:Objective: Arthrogenic muscle inhibition (AMI) is a presynaptic, ongoing Reflex inhibition of joint musculature after distension or damage to the joint. The extent to which therapeutic interventions affect AMI is unknown. The purpose of this study was to verify that the vastus medialis (VM) is inhibited using the knee joint effusion model and to investigate the effects of cryotherapy and transcutaneous electric nerve stimulation (TENS) on AMI using this model. Design and Setting: A3 3 6 analysis of variance was used to compare Hoffmann-Reflex data for treatment groups (cryotherapy, TENS, and control) across time (preinjection, postinjection, and 15, 30, 45, and 60 minutes after injection). Subjects: Thirty neurologically sound volunteers (age 5 21.8 6 2.4 years; height 5 175.6 6 9.6 cm; mass 5 71.5 6 13.3 kg) participated in this study. Measurements: Hoffmann-Reflex measurements were collected using a percutaneous stimulus to the femoral nerve and surface electromyography of the VM. Results: Hoffmann-Reflex measurements from the cryotherapy and TENS groups were greater than measurements from the control group at 15 and 30 minutes after injection. Measurements from the cryotherapy group were greater than for the TENS group, and measurements for the TENS group were greater than those for the control group at 45 minutes. At 60 minutes, the cryotherapy group measurements were greater than the TENS and control group measures. Measurements at 15, 30, 45, and 60 minutes after injection were reduced compared with the preinjection and postinjection measurements in the control group. Measurements in the cryotherapy group at 30, 45, and 60 minutes were greater than the preinjection, postinjection, and 15-minute data. No differences between time intervals existed in the TENS group. Conclusions: Artificial knee joint effusion results in VM inhibition. Cryotherapy and TENS both disinhibit the quadriceps after knee joint effusion, and cryotherapy further facilitates the quadriceps motoneuron pool. Cryotherapy treatment resulted in facilitation of the VM motoneuron pool during the post-treatment phase. The TENS treatment failed to disinhibit the VM motoneuron pool by 30 minutes postinjection.
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cryotherapy and transcutaneous electric neuromuscular stimulation decrease arthrogenic muscle inhibition of the vastus medialis after knee joint effusion
Journal of Athletic Training, 2002Co-Authors: J T Hopkins, Christopher D Ingersoll, Jeffrey E Edwards, Thomas E KlootwykAbstract:OBJECTIVE: Arthrogenic muscle inhibition (AMI) is a presynaptic, ongoing Reflex inhibition of joint musculature after distension or damage to the joint. The extent to which therapeutic interventions affect AMI is unknown. The purpose of this study was to verify that the vastus medialis (VM) is inhibited using the knee joint effusion model and to investigate the effects of cryotherapy and transcutaneous electric nerve stimulation (TENS) on AMI using this model. DESIGN AND SETTING: A 3 x 6 analysis of variance was used to compare Hoffmann-Reflex data for treatment groups (cryotherapy, TENS, and control) across time (preinjection, postinjection, and 15, 30, 45, and 60 minutes after injection). SUBJECTS: Thirty neurologically sound volunteers (age = 21.8 +/- 2.4 years; height = 175.6 +/- 9.6 cm; mass = 71.5 +/- 13.3 kg) participated in this study. MEASUREMENTS: Hoffmann-Reflex measurements were collected using a percutaneous stimulus to the femoral nerve and surface electromyography of the VM. RESULTS: Hoffmann-Reflex measurements from the cryotherapy and TENS groups were greater than measurements from the control group at 15 and 30 minutes after injection. Measurements from the cryotherapy group were greater than for the TENS group, and measurements for the TENS group were greater than those for the control group at 45 minutes. At 60 minutes, the cryotherapy group measurements were greater than the TENS and control group measures. Measurements at 15, 30, 45, and 60 minutes after injection were reduced compared with the preinjection and postinjection measurements in the control group. Measurements in the cryotherapy group at 30, 45, and 60 minutes were greater than the preinjection, postinjection, and 15-minute data. No differences between time intervals existed in the TENS group. CONCLUSIONS: Artificial knee joint effusion results in VM inhibition. Cryotherapy and TENS both disinhibit the quadriceps after knee joint effusion, and cryotherapy further facilitates the quadriceps motoneuron pool. Cryotherapy treatment resulted in facilitation of the VM motoneuron pool during the post-treatment phase. The TENS treatment failed to disinhibit the VM motoneuron pool by 30 minutes postinjection.
Mark A Hoffman - One of the best experts on this subject based on the ideXlab platform.
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The Hoffmann Reflex is different in men and women.
Neuroreport, 2018Co-Authors: Mark A Hoffman, Marc F. Norcross, Samuel T. JohnsonAbstract:To compare the maximum Hoffmann Reflex (H-Reflex) and the maximum M-wave (H : M) ratio of the H-Reflex in men and women when all participants showed similar saliva levels of estradiol and progesterone. This is a cohort design study involving healthy men and women with a mean age of 22.4±3.4 years. T
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intersession reliability of Hoffmann Reflex gain and presynaptic inhibition in the human soleus muscle
Archives of Physical Medicine and Rehabilitation, 2009Co-Authors: Bradley T Hayes, Rod A Harter, Jeffrey J Widrick, Charlie A Hickslittle, Mark A HoffmanAbstract:Abstract Hayes BT, Hicks-Little CA, Harter RA, Widrick JJ, Hoffman MA. Intersession reliability of Hoffmann Reflex gain and presynaptic inhibition in the human soleus muscle. Objective To determine the day-to-day reliability of Hoffmann Reflex (H-Reflex) gain and presynaptic inhibition of spinal Reflexes in the human soleus muscle. Design Controlled trial. Setting Research laboratory. Participants Volunteers (N=30; mean ± SD age, 23.4±3.9y; height, 175.64±10.87cm; mass, 84.50±24.18kg) with no history of lower extremity pathology and/or injury participated. Interventions Subjects lay prone with the head, shoulders, arms, and hips supported in a static position by a massage body pillow and the ankle positioned at 90°. Recording electrodes were placed over the soleus and tibialis anterior muscle bellies, and the stimulating electrodes were positioned over the tibial nerve in the popliteal space and the common peroneal nerve near the fibular head. Main Outcome Measures The H-Reflex and motor wave recruitment curves were then measured and recorded. Presynaptic inhibition was also assessed in the soleus muscle, and a conditioning stimulation of the common peroneal nerve (1 × motor threshold=motor threshold) was used prior to soleus H-Reflex measurement. Two testing sessions took place between 2 and 7 days, and each session occurred at the same time of day. Results Assessments of H-Reflex gain and presynaptic inhibition yielded test-retest reliability of R equal to . 95 and .91, respectively. Conclusions Measures of presynaptic inhibition and H-Reflex gain (H slope/M slope) in the human soleus muscle are consistent and reliable day to day.
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the Hoffmann Reflex methodologic considerations and applications for use in sports medicine and athletic training research
Journal of Athletic Training, 2004Co-Authors: Riann M Palmieri, Christopher D Ingersoll, Mark A HoffmanAbstract:OBJECTIVE To discuss the proper methods used to elicit the Hoffmann Reflex (H-Reflex) and to present different situations in which this tool can be used in sports medicine research. DATA SOURCES We searched MEDLINE and SPORT Discus from 1960 to 2004 using the key words Hoffmann Reflex, H-Reflex, and methodology. The remaining citations were collected from references of similar papers. DATA SYNTHESIS Numerous authors have used the H-Reflex as a tool to examine neurologic conditions. However, few have used the H-Reflex to examine neuromuscular impairments after sport injuries. Several studies were available describing the appropriate methods to elicit the H-Reflex and examining the reliability of this measurement in different muscles. CONCLUSIONS/RECOMMENDATIONS The H-Reflex is a valuable tool to evaluate neurologic function in various populations. However, because of the sensitivity of this measurement to extraneous factors, care must be taken when eliciting the H-Reflex. We discuss recommendations on how to elicit the H-Reflex and how to appropriately present methods in a manuscript.
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Simultaneous Hoffmann Reflex measurements in multiple muscles around the ankle
The International journal of neuroscience, 2003Co-Authors: Mark A Hoffman, Riann M Palmieri, Christopher D IngersollAbstract:Measurement of the Hoffmann Reflex (H-Reflex) provides an estimate of alpha motoneuron activity in the target motoneuron (MN) pool. The H-Reflex has been assessed for a wide variety of reasons in neuroscience research. However, the majority of protocols have focused on the assessment of only one muscle and its corresponding motoneuron pool at any instant. Previously established protocols do not simultaneously assess Reflex activity in multiple muscles elicited from a single stimulation. This new protocol allows for assessment of alpha motoneuron activity in three muscles around the ankle joint from a single stimulus to the sciatic nerve. To elicit the responses, the sciatic nerve was stimulated just prior to its bifurcation into the tibial and common peroneal nerves in the popliteal fossa. Electromyographic recording electrodes were placed on the tibialis anterior, peroneal longus, and soleus muscles. The 1-ms square wave pulse was delivered every 15 s during the recruitment curve mapping. The maximum H Reflex and M waves were measured in each muscle and their ratios calculated. The measurement of these ratios simultaneously allows for assessment of the cumulative alpha motoneuron activity about the ankle at a given point in time.
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The effects of vision and task complexity on Hoffmann Reflex gain
Brain Research, 1995Co-Authors: Mark A Hoffman, David M. KocejaAbstract:Abstract Previous research demonstrates modulation of the Hoffmann Reflex amplitude and gain during changes in environmental conditions. H-Reflex gain (defined in this study as the ratio of H-Reflex amplitude to average soleus background EMG) is considered a functional measure of Reflex modulation. In this study the effects of manipulating visual input and surface stability were investigated in 17 subjects under four experimental conditions: (1) vision-stable surface, (2) no vision-stable surface, (3) vision-unstable surface, and (4) no vision-unstable surface. In each condition, subjects performed fifteen trials of a single leg stance for 7 s. The H-Reflex was electrically elicited at the end of each trial by delivering a 1 ms square wave stimulation to the tibial nerve in the popliteal fossa of the dominant leg. Average background EMG (40 ms window) and peak to peak amplitude of the H-Reflex were measured online for each trial (sampling rate = 2 kHz). An analysis of variance revealed significant decreases in H-Reflex gain for the visual ( F 1, 16 = 4.71, P ) and, surface conditions ( F 1, 16 = 7.67, P ), however there was no interaction ( F 1, 16 = 0.48, P ), between these variables. These results suggest that supraspinal mechanisms, possibly presynaptic inhibition, modulate H-Reflex gain across environmental conditions. We conclude that visual and possibly cutaneous inputs were responsible for driving presynaptic inhibition and thus decreasing H-Reflex gain.
Danilo De Oliveira Silva - One of the best experts on this subject based on the ideXlab platform.
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Patellar Tendon Reflex and Vastus Medialis Hoffmann Reflex Are Down Regulated and Correlated in Women With Patellofemoral Pain
Archives of physical medicine and rehabilitation, 2018Co-Authors: Marcella Ferraz Pazzinatto, Danilo De Oliveira Silva, Fernando Henrique Magalhães, Evangelos Pappas, Amanda Schenatto Ferreira, Marina Cabral Waiteman, Fábio Mícolis De AzevedoAbstract:Abstract Objectives The aims of this study were threefold: (1) to compare the amplitude of patellar tendon Reflex (T-Reflex) between women with patellofemoral pain (PFP) and pain-free controls; (2) to compare the amplitude of vastus medialis Hoffmann Reflex (VM H-Reflex) between women with PFP and pain-free controls; (3) to investigate the association between the amplitude of patellar T-Reflex and VM H-Reflex in women with PFP and pain-free controls. Design Cross-sectional observational study. Setting Laboratory of biomechanics and motor control. Participants Thirty women with PFP and 30 pain-free women aged 18 to 35 years (N=60). Main Outcome Measures Peak-to-peak amplitudes of maximal VM H-Reflex (elicited via electrical stimulation on the femoral nerve) and patellar T-Reflex (elicited via mechanical percussion on the patellar tendon) were estimated. Results Women with PFP had significant lower amplitude of patellar T-Reflex (mean difference=0.086; 95% confidence interval=0.020 to 0.151; P=.010; moderate effect) and VM H-Reflex (mean difference=0.150; 95% confidence interval =0.073 to 0.227; P Conclusions As the T-Reflex is easier to perform than H-Reflex assessments in a clinical setting, it represents a feasible option to assess the impaired excitability of the stretch Reflex pathway associated with PFP.
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Vastus Medialis Hoffmann Reflex Excitability Is Associated With Pain Level, Self-Reported Function, and Chronicity in Women With Patellofemoral Pain
Archives of physical medicine and rehabilitation, 2016Co-Authors: Danilo De Oliveira Silva, Fernando Henrique Magalhães, Nathálie Clara Faria, Deisi Ferrari, Marcella Ferraz Pazzinatto, Evangelos Pappas, Fábio Mícolis De AzevedoAbstract:Abstract Objective To determine the association between the amplitude of vastus medialis (VM) Hoffmann Reflex (H-Reflex) and pain level, self-reported physical function, and chronicity of pain in women with patellofemoral pain (PFP). Design Cross-sectional study. Setting Laboratory of biomechanics and motor control. Participants Women diagnosed with PFP (N=15) aged 18 to 35 years. Interventions Not applicable. Main Outcome Measures Data on worst pain level during the previous month, self-reported physical function, and symptom duration (chronicity) were collected from the participants. Maximum evoked responses were obtained by electrical stimulation applied to the femoral nerve and peak-to-peak amplitudes of normalized maximal H-Reflexes (maximal Hoffmann Reflex/maximal motor wave ratios) of the VM were calculated. A Pearson product-moment correlation matrix ( r ) was used to explore the relations between the amplitude of VM H-Reflex and worst pain during the previous month, self-reported function, and chronicity of pain. Results Strong negative correlations were found between the amplitude of VM H-Reflex and worst pain in the previous month ( r =−.71; P =.003) and chronicity ( r =−.74; P =.001). A strong positive correlation was found between the amplitude of VM H-Reflex and self-reported physical function ( r =.62; P =.012). Conclusions The strong and significant relations reported in this study suggest that women with PFP showing greater VM H-Reflex excitability tend to have lower pain, better physical function, and more recent symptoms. Therefore, rehabilitation strategies designed to increase the excitability of the monosynaptic stretch Reflex should be considered in the treatment of women with PFP if their effectiveness is demonstrated in future studies.
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Lower Amplitude of the Hoffmann Reflex in Women With Patellofemoral Pain: Thinking Beyond Proximal, Local, and Distal Factors
Archives of physical medicine and rehabilitation, 2016Co-Authors: Danilo De Oliveira Silva, Fernando Henrique Magalhães, Nathálie Clara Faria, Deisi Ferrari, Marcella Ferraz Pazzinatto, Evangelos Pappas, Fábio Mícolis De AzevedoAbstract:Abstract Objectives To investigate whether vastus medialis (VM) Hoffmann Reflexes (H-Reflexes) differ on the basis of the presence or absence of patellofemoral pain (PFP) and to assess the capability of VM H-Reflex measurements in accurately discriminating between women with and without PFP. Design Cross-sectional study. Setting Laboratory of biomechanics and motor control. Participants Women (N=30) aged 18 to 35 years were recruited, consisting of 2 groups: women with PFP (n=15) and asymptomatic controls (n=15). Interventions Not applicable. Main Outcome Measures Maximum evoked responses were obtained by electrical stimulation applied to the femoral nerve, and peak-to-peak amplitudes of maximal Hoffmann Reflex (Hmax) and maximal motor wave (Mmax) ratios were calculated. Independent samples t tests were performed to identify differences between groups, and a receiver operating characteristic curve was constructed to assess the discriminatory capability of VM H-Reflex measurements. Results VM Hmax/Mmax ratios were significantly lower in participants with PFP than in pain-free participants ( P =.007). In addition, the VM Hmax/Mmax ratios presented large and balanced discriminatory capability values (sensitivity, 73%; specificity, 67%). Conclusions This study is the first to show that VM H-Reflexes are lower in women with PFP than in asymptomatic controls. Therefore, increasing the excitation of the spinal cord in PFP participants may be essential to maintaining the gains acquired during the rehabilitation programs.
Marcella Ferraz Pazzinatto - One of the best experts on this subject based on the ideXlab platform.
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Patellar Tendon Reflex and Vastus Medialis Hoffmann Reflex Are Down Regulated and Correlated in Women With Patellofemoral Pain
Archives of physical medicine and rehabilitation, 2018Co-Authors: Marcella Ferraz Pazzinatto, Danilo De Oliveira Silva, Fernando Henrique Magalhães, Evangelos Pappas, Amanda Schenatto Ferreira, Marina Cabral Waiteman, Fábio Mícolis De AzevedoAbstract:Abstract Objectives The aims of this study were threefold: (1) to compare the amplitude of patellar tendon Reflex (T-Reflex) between women with patellofemoral pain (PFP) and pain-free controls; (2) to compare the amplitude of vastus medialis Hoffmann Reflex (VM H-Reflex) between women with PFP and pain-free controls; (3) to investigate the association between the amplitude of patellar T-Reflex and VM H-Reflex in women with PFP and pain-free controls. Design Cross-sectional observational study. Setting Laboratory of biomechanics and motor control. Participants Thirty women with PFP and 30 pain-free women aged 18 to 35 years (N=60). Main Outcome Measures Peak-to-peak amplitudes of maximal VM H-Reflex (elicited via electrical stimulation on the femoral nerve) and patellar T-Reflex (elicited via mechanical percussion on the patellar tendon) were estimated. Results Women with PFP had significant lower amplitude of patellar T-Reflex (mean difference=0.086; 95% confidence interval=0.020 to 0.151; P=.010; moderate effect) and VM H-Reflex (mean difference=0.150; 95% confidence interval =0.073 to 0.227; P Conclusions As the T-Reflex is easier to perform than H-Reflex assessments in a clinical setting, it represents a feasible option to assess the impaired excitability of the stretch Reflex pathway associated with PFP.
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Vastus Medialis Hoffmann Reflex Excitability Is Associated With Pain Level, Self-Reported Function, and Chronicity in Women With Patellofemoral Pain
Archives of physical medicine and rehabilitation, 2016Co-Authors: Danilo De Oliveira Silva, Fernando Henrique Magalhães, Nathálie Clara Faria, Deisi Ferrari, Marcella Ferraz Pazzinatto, Evangelos Pappas, Fábio Mícolis De AzevedoAbstract:Abstract Objective To determine the association between the amplitude of vastus medialis (VM) Hoffmann Reflex (H-Reflex) and pain level, self-reported physical function, and chronicity of pain in women with patellofemoral pain (PFP). Design Cross-sectional study. Setting Laboratory of biomechanics and motor control. Participants Women diagnosed with PFP (N=15) aged 18 to 35 years. Interventions Not applicable. Main Outcome Measures Data on worst pain level during the previous month, self-reported physical function, and symptom duration (chronicity) were collected from the participants. Maximum evoked responses were obtained by electrical stimulation applied to the femoral nerve and peak-to-peak amplitudes of normalized maximal H-Reflexes (maximal Hoffmann Reflex/maximal motor wave ratios) of the VM were calculated. A Pearson product-moment correlation matrix ( r ) was used to explore the relations between the amplitude of VM H-Reflex and worst pain during the previous month, self-reported function, and chronicity of pain. Results Strong negative correlations were found between the amplitude of VM H-Reflex and worst pain in the previous month ( r =−.71; P =.003) and chronicity ( r =−.74; P =.001). A strong positive correlation was found between the amplitude of VM H-Reflex and self-reported physical function ( r =.62; P =.012). Conclusions The strong and significant relations reported in this study suggest that women with PFP showing greater VM H-Reflex excitability tend to have lower pain, better physical function, and more recent symptoms. Therefore, rehabilitation strategies designed to increase the excitability of the monosynaptic stretch Reflex should be considered in the treatment of women with PFP if their effectiveness is demonstrated in future studies.
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Lower Amplitude of the Hoffmann Reflex in Women With Patellofemoral Pain: Thinking Beyond Proximal, Local, and Distal Factors
Archives of physical medicine and rehabilitation, 2016Co-Authors: Danilo De Oliveira Silva, Fernando Henrique Magalhães, Nathálie Clara Faria, Deisi Ferrari, Marcella Ferraz Pazzinatto, Evangelos Pappas, Fábio Mícolis De AzevedoAbstract:Abstract Objectives To investigate whether vastus medialis (VM) Hoffmann Reflexes (H-Reflexes) differ on the basis of the presence or absence of patellofemoral pain (PFP) and to assess the capability of VM H-Reflex measurements in accurately discriminating between women with and without PFP. Design Cross-sectional study. Setting Laboratory of biomechanics and motor control. Participants Women (N=30) aged 18 to 35 years were recruited, consisting of 2 groups: women with PFP (n=15) and asymptomatic controls (n=15). Interventions Not applicable. Main Outcome Measures Maximum evoked responses were obtained by electrical stimulation applied to the femoral nerve, and peak-to-peak amplitudes of maximal Hoffmann Reflex (Hmax) and maximal motor wave (Mmax) ratios were calculated. Independent samples t tests were performed to identify differences between groups, and a receiver operating characteristic curve was constructed to assess the discriminatory capability of VM H-Reflex measurements. Results VM Hmax/Mmax ratios were significantly lower in participants with PFP than in pain-free participants ( P =.007). In addition, the VM Hmax/Mmax ratios presented large and balanced discriminatory capability values (sensitivity, 73%; specificity, 67%). Conclusions This study is the first to show that VM H-Reflexes are lower in women with PFP than in asymptomatic controls. Therefore, increasing the excitation of the spinal cord in PFP participants may be essential to maintaining the gains acquired during the rehabilitation programs.