Background: Anterior cruciate ligament deficiency (ACL-D) causes dysfunction in the quadriceps femoris muscle, and this dysfunction hampers a safe return to sports. However, how the dysfunctional quadriceps femoris muscle affects instantaneous re-programming of motor command in response to unpredictable events remains unknown. This study aimed to examine the effects of ACL-D on re-programming of preparatory muscle activity during an unpredictable landing task.
View Article and Find Full Text PDFArthrogenic muscle inhibition (AMI) is induced by pathological knee conditions. The present study aimed to investigate the effect of tactile stimulation on reflex changes induced by simulated AMI during unpredictable landing performances. Twenty participants performed six unilateral landing tasks: 15 cm normal landing (15NL), 30 cm normal landing (30NL), surprise landing (SL), 30 cm normal landing following vibration (30NLV), SL following vibration (SLV), and SL following vibration with Kinesiology tape (SLK).
View Article and Find Full Text PDFPersistent quadriceps weakness after anterior cruciate ligament (ACL) reconstruction is a common hurdle to efficient rehabilitation. Therefore, we evaluated a new treatment strategy for athletes with ACL reconstruction. Eleven athletes with unilateral ACL reconstruction performed one set of flywheel Bulgarian split squats to exhaustion with a maximum knee extension of 60°, over 16 sessions, on their reconstructed limb.
View Article and Find Full Text PDFContext: 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. This impairment is termed arthrogenic muscle inhibition (AMI).
View Article and Find Full Text PDFAims: Critical congenital heart disease (CCHD) requires surgery or catheter intervention within the first year of life; delayed diagnoses result in worsened outcomes. In Japan, there are few reports of delayed CCHD diagnosis. We investigated the diagnoses and factors associated with the late detection of CCHD.
View Article and Find Full Text PDFNo studies in ACL-D individuals have examined neuromuscular adaptations during landing from a jump where an unexpected mechanical event changes the pre-programmed course of movement. The purpose of this study was to compare pre- and post-landing muscle activation in ACL-D individuals and uninjured controls during normal and surprise landings. Nineteen ACL-D and 17 uninjured volunteered.
View Article and Find Full Text PDFJ Matern Fetal Neonatal Med
March 2022
Background: The predictive ability of neonatal illness severity scores for mortality or morbidity in extremely premature infants has not been extensively studied. We aimed to evaluate the ability of neonatal illness severity scores [Clinical Risk Index for Babies II (CRIB II), Score for Neonatal Acute Physiology II (SNAP-II), and SNAP-Perinatal Extension II (SNAPPE-II)] in predicting mortality and short-term morbidity of extremely premature infants.
Methods: This retrospective study involved 171 infants with gestational age (GA) between 22 and 27 weeks who were admitted to the NICU during 2010-2017.
Circumference measurements have been used to estimate muscle cross-sectional area (CSA) in clinical settings. Measurements of thigh circumference are affected by muscle and subcutaneous fat (SF). In fact, SF could increase over a short period.
View Article and Find Full Text PDFUnlabelled: Background/ Aims: Owing to practical and technical developments, continuous renal replacement therapy (CRRT) has been administered even in critically ill neonates. In this study, the complications in CRRT for neonates were examined to establish a safe CRRT.
Methods: This retrospective study reviewed the clinical records of neonates who underwent CRRT at our neonatal intensive care unit between 2009 and 2017.
Vitamin K deficiency in pregnant women causes intracranial hemorrhage (ICH) in fetuses. Fetal ICH frequently causes life-threatening and persistent neurological damage. However, indicators for preventing fetal ICH are not established.
View Article and Find Full Text PDFObjective: Preterm infants are at high risk for developmental delay, epilepsy, and autism spectrum disorders. Some reports have described associations between these conditions and gamma-aminobutyric acid (GABA) dysfunction; however, no study has evaluated temporal changes in GABA in preterm infants. Therefore, we assessed temporal changes in brain metabolites including GABA using single-voxel 3-Tesla (T) proton magnetic resonance spectroscopy (H-MRS) in preterm infants with normal development.
View Article and Find Full Text PDFUnlabelled: We present a simple technique for patterning Au top electrodes in vertical molecular junction devices that have the conductive polymer, poly(3,4-ethylene dioxythiophene)-poly(4-styrene sulfonate) (
Pedot: PSS), as a contact layer between the self-assembled monolayer and the Au top electrode. In this method, a thermally curable photoresist of SU-8 is used to define the areas where the top electrodes are formed. The hydrophobicity and low surface energy of the cured SU-8 facilitates selective deposition of
Pedot: PSS onto the defined top electrode areas of the device through solution dewetting, and also enables the physical peeling of the Au top electrodes deposited on the SU-8 layers using an adhesion tape.
Purpose: To investigate temporal changes in brain metabolites during the first year of life in preterm infants using multivoxel proton magnetic resonance spectroscopy ((1)H-MRS).
Methods: Seventeen infants born at 29 (25-33) gestational week (median, range) weighing 1104 (628-1836) g underwent 1.5-T multivoxel (1)H-MRS at 42 postconceptional week (PCW) and at 3, 6, 9, and 12 months after.
Objective: Prolonged vibration stimulation to normal individuals could lead to muscle weakness attributable to attenuation of afferent feedback. This weakness is neurophysiologically similar to that seen in patients with knee injury. Theoretically, increasing input to gamma motor neurons could reverse this weakness.
View Article and Find Full Text PDFKnee Surg Sports Traumatol Arthrosc
November 2012
Purpose: This study was conducted to identify factors other than morphological muscle strength factors that affect injured and uninjured sides of knee flexors with anterior cruciate ligament (ACL) lesions.
Methods: The study population consisted of 22 patients with ACL lesions. Their hamstring muscle volume was measured on MRI, and muscle torque per muscle volume was calculated as the peak torque of knee flexion divided by hamstring muscle volume.
Coronary artery stenosis is seen in 10-45% of patients with Takayasu's arteritis (TA) and coronary ostia are most frequently involved. It may cause angina pectoris and sudden death during the early course of the disease. We describe a 14-year-old girl who first presented with exertional angina and syncope and was diagnosed as having left coronary artery ostial stenosis from TA by using transthoracic echocardiography.
View Article and Find Full Text PDFThe purpose of this study was to investigate the effect of surgery on the gamma-loop in the quadriceps of patients with ACL injuries. We compared the response to vibration stimulation in subjects with ACL repair, subjects with ACL rupture, and normal subjects, by measuring the maximal strength and integrated electromyography (I-EMG) of the quadriceps. Pre-vibration data were obtained from each subject by measuring the MVC of the knee extension and the I-EMG from the vastus medialis, vastus lateralis, and rectus femoris.
View Article and Find Full Text PDFKnee Surg Sports Traumatol Arthrosc
April 2011
Purpose: The purpose of this study was to obtain evidence to support the hypothesis that motor unit recruitment is reduced in the quadriceps femoris (QF) of patients with ACL rupture.
Methods: We compared muscle torque per unit volume in the QF from injured and uninjured sides to normal subjects. If high-threshold motor unit recruitment is reduced in patients with ACL rupture, this reduction will theoretically lead to a reduction in muscle torque per unit volume compared to the control group.
The purpose of present study was to compare the effect of Ia afferent attenuation on the activity of alpha motor neuron (MN) during concentric and eccentric action. Eight male subjects were enrolled in the present study. The experiments consisted of two sessions of MVC measurements, since all subjects performed both maximal concentric and eccentric action.
View Article and Find Full Text PDFThe muscle torque per unit volume of the hamstrings on the injured and uninjured sides in patients with ACL reconstruction were compared with participants with no history of knee injury to examine whether a similar mechanism leading to quadriceps weakness exists in the hamstrings of these patients. The study population consisted of 18 and 52 patients at
Background And Purpose: Gamma loop dysfunction may increase the risk of falls. Therefore, we evaluated gamma loop function in subjects hospitalized after fall injury and examined whether aging affects the gamma loop.
Methods: Maximal voluntary contraction (strength) of knee extension and integrated electromyography (I-EMG) of the quadriceps femoris were examined to evaluate the activities of alpha motoneurons before and after 20-min vibration applied to the quadriceps femoris.
Med Sci Sports Exerc
November 2003
Purpose: In our previous study, we found that injection of lidocaine into intact knees reduced the maximal voluntary contraction (MVC) and integrated electromyogram (I-EMG) of the quadriceps femoris (QF). This study was designed to investigate changes in the MVC and I-EMG of the QF in response to lidocaine, in patients with anterior cruciate ligament (ACL) lesion, to evaluate alpha-motoneuron activity innervating the QF.
Methods: The MVC of knee extension and I-EMG of the vastus medialis (VM), vastus lateralis (VL), and rectus femoris (RF) muscles were measured in eight patients with ruptured ACL, before and after lidocaine injection into the knee.
Purpose: The aim of our study was to test for any neurophysiological abnormality in the gamma loop in the quadriceps femoris muscle on the uninjured side of patients with unilateral rupture of the anterior cruciate ligament (ACL).
Methods: Maximal voluntary contraction of knee extension and integrated electromyography (I-EMG) of the vastus medialis, vastus lateralis, and rectus femoris were measured in the uninjured limb of 13 patients with unilateral ACL rupture and 10 normal subjects, before and after 20-min vibration stimulation applied to the infrapatellar tendon.
Results: The mean percentage changes of maximal voluntary contraction and I-EMG in quadriceps femoris of the uninjured side of patients with ACL rupture were significantly different from those of the control group.
Med Sci Sports Exerc
September 2002
Purpose: The purpose of this study was to test the hypothesis that loss of afferent feedback due to rupture of anterior cruciate ligament (ACL) is the cause of quadriceps femoris (QF) weakness through gamma loop. Two experiments were designed to prove our hypothesis.
Methods: In experiment 1, the maximal voluntary contraction (MVC) of knee extension and integrated electromyogram (I-EMG) of vastus medialis (VM), vastus lateralis (VL), and rectus femoris (RF) were measured in 13 patients with ruptured ACL and 7 healthy volunteers before and after injection of anesthetic agent into the knee.