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Chong Bum Chang - One of the best experts on this subject based on the ideXlab platform.
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Retrospective study of relationship between Vastus Medialis volume on SPECT-CT and outcome of unilateral total knee arthroplasty.
Medicine, 2021Co-Authors: Hyeong Jik Kim, Hyung Jun Park, Moon Jong Chang, Seung Baik Kang, Yu Kyeong Kim, Chong Bum ChangAbstract:ABSTRACT Although the importance of quadriceps femoris function was reported previously, little is known about volume-related factors and their effects on clinical outcomes after total knee arthroplasty (TKA). We sought to determine whether there was a bilateral difference in Vastus Medialis Muscle volume measured on single-photon emission computed tomography-computed tomography (SPECT-CT) in patients who underwent unilateral TKA. We also aimed to determine whether Vastus Medialis volume was related to osteoarthritis (OA) severity or scintigraphic uptake degree around the knee joint on SPECT-CT. And finally, we attempted to investigate the factors, such as Vastus Medialis volume and scintigraphic uptake degree, associated with the functional outcomes of TKA.This retrospective study included 50 patients (41 female, 9 male) undergone unilateral TKA due to primary OA. The maximal cross-sectional area of the Vastus Medialis was measured on axial SPECT-CT images. Scintigraphic uptake degrees and Kellgren-Lawrence (K-L) grade at the tibiofemoral joints were assessed. We compared maximal cross-sectional area of the Vastus Medialis on SPECT-CT for difference of bilateral lower limbs. We also analyzed the relationship between volume of Vastus Medialis and scintigraphic uptake measured on SPECT-CT and the severity of OA on conventional radiographs. The clinical outcomes were evaluated using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index at baseline and at 1 and 2 years after surgery. The relationship between preoperative Muscle volume and scintigraphic uptake on SPECT-CT and WOMAC index was analyzed.The amount of Muscle volume measured on SPECT-CT was smaller in operated limb in patients who underwent unilateral TKA. Preoperative Vastus Medialis Muscle volume was not related to preoperative OA severity measured on conventional radiographs and scintigraphic uptake on SPECT-CT. However, a decreased Vastus Medialis Muscle volume was related to worse clinical outcomes after TKA (P = .045), whereas the degree of scintigraphic uptake on SPECT-CT was not associated with postoperative clinical outcomes.Muscle volume of Vastus Medialis was decreased in the operated knee than in the nonoperated knee, and that was correlated with worse postoperative results. Even if the preoperative volume of Vastus Medialis were not related to OA severity on conventional radiographs and scintigraphic uptake on SPECT-CT, preservation and improvement of the Muscle mass of the knee undergoing TKA is important.
Ashril Yusof - One of the best experts on this subject based on the ideXlab platform.
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Electromyography Assessments of the Vastus Medialis Muscle during Soccer Instep Kicking between Dynamic and Static Stretching
Journal of Human Kinetics, 2010Co-Authors: Mohammadtaghi Amiri-khorasani, Noor Osman, Ashril YusofAbstract:Electromyography Assessments of the Vastus Medialis Muscle during Soccer Instep Kicking between Dynamic and Static StretchingThe purpose of this study was to examine the effects of static and dynamic stretching within a pre-exercise warm-up on Vastus Medialis Muscle activity during instep kicking and ball velocity in soccer players. The kicking motions of dominant legs were captured from using six synchronized high-speed infra-red cameras at 200 Hz and Electromyography at 100 Hz. There was significant difference in Vastus Medialis activity after dynamic stretching relative to no stretching condition (0.12 ± 0.06 mV) versus static stretching relative to no stretching condition (-0.21 ± 0.10 mV) with p < 0.001). In addition, there was also a significant difference in ball velocity after dynamic stretching relative to no stretching condition (4.53 ± 2.10 m/s) versus static stretching relative to no stretching condition (-1.48 ± 2.43 m/s) with p < 0.003. We concluded that dynamic stretching during the warm-up, as compared to static stretching, is probably more effective as preparation for optimal Muscle activity and finally have high ball velocity which is required in soccer.
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Electromyography Assessments of the Vastus Medialis Muscle during Soccer Instep Kicking between Dynamic and Static Stretching
Journal of Human Kinetics, 2010Co-Authors: Mohammadtaghi Amiri-khorasani, Noor Azuan Abu Osman, Ashril YusofAbstract:The purpose of this study was to examine the effects of static and dynamic stretching within a pre‐exercise warm‐up on Vastus Medialis Muscle activity during instep kicking and ball velocity in soccer players. The kicking motions of dominant legs were captured from using six synchronized high‐speed infra‐red cameras at 200 Hz and Electromyography at 100 Hz. There was significant difference in Vastus Medialis activity after dynamic stretching relative to no stretching condition (0.12 ± 0.06 mV) versus static stretching relative to no stretching condition (‐0.21 ± 0.10 mV) with p < 0.001). In addition, there was also a significant difference in ball velocity after dynamic stretching relative to no stretching condition (4.53 ± 2.10 m/s) versus static stretching relative to no stretching con‐ dition (‐1.48 ± 2.43 m/s) with p < 0.003. We concluded that dynamic stretching during the warm‐up, as compared to static stretching, is probably more effective as preparation for optimal Muscle activity and finally have high ball velocity which is required in soccer.
Dario Farina - One of the best experts on this subject based on the ideXlab platform.
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Motor unit conduction velocity during sustained contraction of the Vastus Medialis Muscle
Experimental brain research, 2007Co-Authors: Nosratollah Hedayatpour, Lars Arendt-nielsen, Dario FarinaAbstract:The aim of the study was to analyze motor unit conduction velocity at varying force of the Vastus Medialis Muscle during sustained contraction. Surface (8-electrode array) and intramuscular (two wire electrodes) EMG signals were recorded from the distal part of the dominant Vastus Medialis Muscle of ten healthy male subjects. The subjects sat on a chair with the knee 90° flexed and performed seven 180-s long contractions at forces in the range 2.5–30% of the maximal voluntary contraction force. For each force level, the discharge patterns of the newly recruited motor units with respect to the previous force level were identified from the intramuscular recordings and used as trigger for averaging the surface EMG signals. Motor unit conduction velocity was estimated from the averaged surface EMG. Average discharge rate at which motor units were analyzed was the same for each force level (mean ± SD, 8.3 ± 0.8 pulses per second). Motor unit conduction velocity at the beginning of the contraction and its rate of change over time increased with force (P < 0.05). Conduction velocity at the beginning of the contraction estimated from the interference surface EMG (4.44 ± 0.66 m/s) and from single motor units (4.75 ± 0.56 m/s) were positively correlated (R 2 = 0.46; P < 0.0001) but significantly different (P < 0.05). The results indicate that single motor unit conduction velocity and its rate of change during sustained contraction, assessed at a fixed discharge rate, depend on force level.
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Cancellation of surface action potential amplitude in motor units of the Vastus Medialis Muscle
Neuroscience, 2007Co-Authors: Corrado Cescon, Francesco Negro, Roger M. Enoka, Dario FarinaAbstract:The surface EMG underestimates the amount of motor unit activity due to the loss of information that occurs when positive and negative phases of action potentials cancel one another and reduce the amplitude of the signal (cancellation) It has been shown in simulation [1] that cancellation of action potentials of individual motor units is linearly correlated to the decrease in size of the spike-triggered average of the rectified or squared EMG Thus, spike-triggered averaging [2,3] of the surface EMG can be in principle used to estimate amplitude cancellation but this has not been supported theoretically or verified experimentally Theoretical analysis of cancellation of single motor unit action potentials in relation to spike-triggered averaging to explain the results reported previously in simulation [1] Validation of the theoretical predictions with experimental recordings of motor units in the Vastus Medialis Muscle The amount of cancellation of action potentials of individual motor units has been theoretically proven to depend only on the ratio between the RMS of the motor unit action potential and the RMS of the interference signal. According to this theoretical derivation, small surface action potentials are cancelled more than large action potentials. The ratio between the spike-triggered average of the interference and the squared surface EMG is theoretically equivalent to the degree of cancellation of the action potential, which explains the results reported in [1]. The theoretical predictions have been experimentally validated for the Vastus Medialis Muscle. Cancellation of action potential amplitude of single motor units can thus be theoretically predicted and experimentally quantified.
Arnold De Haan - One of the best experts on this subject based on the ideXlab platform.
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De relatieve bijdrage van de m. Vastus Medialis aan het totale kniestrekkend moment is kniehoek onafhankelijk
2009Co-Authors: J. De Ruiter, Arnold Huurnink, G. Hoddenbach, Arnold De HaanAbstract:The relative contribution of the Vastus Medialis Muscle to total isometric knee extension torque at four different knee flexion angles (10, 30, 60 en 90°) was investigated. At each knee angle, in ten healthy male subjects, the surface EMG was obtained during voluntary submaximal [20%) contractions and maximal knee extension torque was established using femoral nerve stimulation. Subsequently, the Vastus Medialis Muscle was functionally eliminated by selective electrical surface stimulation. Following Vastus Medialis elimination, total knee extension torque during maximal femoral nerve stimulation decreased by about 25% which was similar among knee angles (p>0.05). In addition, during the submaximal voluntary contractions the increases in EMG of the other quadriceps Muscle heads, compensating for the loss of Vastus Medialis function, were also similar (p>0.05) among knee angles. It was concluded that the Vastus Medialis Muscle had a similar contribution to total knee extension torque over the range (10-90°) of knee angles studied.
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relative torque contribution of Vastus Medialis Muscle at different knee angles
Acta Physiologica, 2008Co-Authors: C. J. De Ruiter, J G Hoddenbach, Arnold De Haan, Arnold HuurninkAbstract:AIM: We investigated the relative contribution of the Vastus Medialis (VM) Muscle to total isometric knee extension torque at 10 degrees , 30 degrees , 60 degrees and 90 degrees knee flexion. In the past a more prominent role of the VM Muscle at more extended knee angles has been put forward. However, different components of the quadriceps Muscle converge via a common distal tendon. We therefore hypothesized that the relative contribution of the VM to total knee extension torque would be similar across angles. METHODS: At each knee angle the EMG isometric torque relations [20%, 25%, 30%, 35% maximal voluntary contraction (MVC)] of the rectus femoris (RF), Vastus lateralis (VL) and VM Muscle were established in 10 healthy male subjects; rectified surface EMG was normalized to M-wave area. Subsequently, the VM was functionally eliminated by selective electrical surface stimulation with occluded blood flow. RESULTS: There was no evidence for preferential activation of VM at any of the knee angles. Following VM elimination, total knee extension torque during maximal femoral nerve stimulation (three pulses at 300 Hz) at 10 degrees , 30 degrees , 60 degrees and 90 degrees , respectively, decreased (P 0.05 among knee angles). In addition, during voluntary contractions at 20% MVC the increases in torque output of RF and VL compensating for the loss of VM function were calculated from the increases in EMG and found to be similar (P > 0.05) at 10 degrees , 30 degrees , 60 degrees and 90 degrees values (%MVC), respectively, were: 9.1 +/- 6.8, 7.5 +/- 2.9, 5.9 +/- 3.7 and 6.9 +/- 3.4. CONCLUSION: The present findings support our hypothesis that the VM contributes similarly to total knee extension torque at different knee angles.
Hyeong Jik Kim - One of the best experts on this subject based on the ideXlab platform.
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Retrospective study of relationship between Vastus Medialis volume on SPECT-CT and outcome of unilateral total knee arthroplasty.
Medicine, 2021Co-Authors: Hyeong Jik Kim, Hyung Jun Park, Moon Jong Chang, Seung Baik Kang, Yu Kyeong Kim, Chong Bum ChangAbstract:ABSTRACT Although the importance of quadriceps femoris function was reported previously, little is known about volume-related factors and their effects on clinical outcomes after total knee arthroplasty (TKA). We sought to determine whether there was a bilateral difference in Vastus Medialis Muscle volume measured on single-photon emission computed tomography-computed tomography (SPECT-CT) in patients who underwent unilateral TKA. We also aimed to determine whether Vastus Medialis volume was related to osteoarthritis (OA) severity or scintigraphic uptake degree around the knee joint on SPECT-CT. And finally, we attempted to investigate the factors, such as Vastus Medialis volume and scintigraphic uptake degree, associated with the functional outcomes of TKA.This retrospective study included 50 patients (41 female, 9 male) undergone unilateral TKA due to primary OA. The maximal cross-sectional area of the Vastus Medialis was measured on axial SPECT-CT images. Scintigraphic uptake degrees and Kellgren-Lawrence (K-L) grade at the tibiofemoral joints were assessed. We compared maximal cross-sectional area of the Vastus Medialis on SPECT-CT for difference of bilateral lower limbs. We also analyzed the relationship between volume of Vastus Medialis and scintigraphic uptake measured on SPECT-CT and the severity of OA on conventional radiographs. The clinical outcomes were evaluated using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index at baseline and at 1 and 2 years after surgery. The relationship between preoperative Muscle volume and scintigraphic uptake on SPECT-CT and WOMAC index was analyzed.The amount of Muscle volume measured on SPECT-CT was smaller in operated limb in patients who underwent unilateral TKA. Preoperative Vastus Medialis Muscle volume was not related to preoperative OA severity measured on conventional radiographs and scintigraphic uptake on SPECT-CT. However, a decreased Vastus Medialis Muscle volume was related to worse clinical outcomes after TKA (P = .045), whereas the degree of scintigraphic uptake on SPECT-CT was not associated with postoperative clinical outcomes.Muscle volume of Vastus Medialis was decreased in the operated knee than in the nonoperated knee, and that was correlated with worse postoperative results. Even if the preoperative volume of Vastus Medialis were not related to OA severity on conventional radiographs and scintigraphic uptake on SPECT-CT, preservation and improvement of the Muscle mass of the knee undergoing TKA is important.
