Noriaki Ichihashi

• PhD
• Professor (Full) at Kyoto University

To clarify the association between infrapatellar fat pad (IFP) stiffness and size with knee osteoarthritis (OA) severity and knee symptoms. This study included 93 participants: 66 with symptomatic medial knee OA (Kellgren–Lawrence grade [KL] ≥ 2) and 27 healthy controls (KL grade 0 or 1) with asymptomatic knees. Shear modulus (stiffness) and thickn...

Skeletal muscle morphology is linked to its function. Extensive literature demonstrates that muscle volume is crucial for determining joint torque exertion, a primary function of muscle. However, whether muscle shape also influences torque exertion capacity remains unclear. This study illustrates that the three-dimensional shape of muscles independ...

Static stretching immediately affects various neuromusculoskeletal components. Among quadriceps muscles, only the rectus femoris (RF) is stretched by hip extension and knee flexion. The aim of this study was to investigate the motor unit (MU) firing behaviors of two synergistic muscles after selective static stretching on only one side. Fourteen ma...

Objectives Although various kinematic parameters have been investigated as factors associated with shoulder and elbow injuries during pitching, the relationship between lower extremity flexibility and such injuries remains unclear. The objective of this meta-analysis was to examine the association between pitching injuries to the shoulder and elbow...

Objective We aimed to examine whether lower‐limb muscle quantity and quality assessed by bioelectric impedance analysis (BIA) were associated with knee extension strength and whether the association differed with knee osteoarthritis (OA) severity. Methods We included 1,525 participants (63.6% women; mean ± SD age 68.0 ± 5.3 years) from the Nagaham...

Background: Overall spinal curvature is evaluated by calculating the difference between the angles of lumbar lordosis (LL) and thoracic kyphosis (TK) and is expressed as LL minus TK (LL-TK). It is unclear whether LL-TK is associated with physical function in community-dwelling older adults and whether it is more relevant than TK or LL alone. Obje...

Background Improving muscle quality to prevent and treat muscle dysfunction is critical. However, effective measures to improve muscle quality remain poorly understood. We investigated the effects of high- and low-velocity resistance training (RT) on muscle quality, mass, and function before and after an 8-week intervention. Hypothesis High-veloci...

Although evidence suggests that intramuscular fat infiltration may influence muscle strength, the precise mechanisms remain unclear. This study aimed to determine whether intramuscular fat infiltration affects muscle mechanical properties during contraction and whether these mechanical properties mediate the relationship between intramuscular fat i...

Context : Piriformis syndrome is often associated with muscle spasms and shortening of the piriformis muscle (PM). Physical therapy, including static stretching of the PM, is one of the treatments for this syndrome. However, the effective stretching position of the PM is unclear in vivo. This study aimed to determine the effective stretching positi...

This study determined whether the acute cartilage response, assessed by cartilage thickness and echo intensity, differs between patients with early-mild knee osteoarthritis (OA) and healthy controls. We recruited 56 women aged ≥ 50 years with Kellgren–Lawrence (KL) grade ≤ 2 (age, 70.6 ± 7.4 years; height, 153.7 ± 5.2 cm; weight, 51.9 ± 8.2 kg). Ba...

We aimed to investigate the muscle coordination differences between a control group and patients with mild and severe knee osteoarthritis (KOA) using muscle synergy analysis and determine whether muscle coordination was associated with symptoms of KOA. Fifty-three women with medial KOA and 19 control patients participated in the study. The gait ana...

Aim This study aimed to calculate the minimal clinically important difference (MCID) for a modified Gait Efficacy Scale (mGES) over 3 years and to clarify the predictors of mGES decline. Methods In total, 87 community‐dwelling older adults were enrolled in this 3‐year longitudinal study. The mGES, fall history and physical function (chair stand fr...

This study investigated the link between pre-stroke and acute-stage physical activity (PA) and sedentary behavior. Forty individuals with stroke (aged 73.6 ± 8.9 years) were enrolled. Post-stroke activity, including metabolic equivalents (METs), sedentary behavior, light PA, and moderate-to-vigorous PA (MVPA), was measured using a tri-axial acceler...

Purpose This study aimed to clarify age‐related changes in the iliocapsularis (IC) using indicators of quantity, quality, and mechanical properties. We also compared the age‐related changes in the IC and other hip muscles. Methods Eighty‐seven healthy women (ages: 21‐82 years, mean age: 45.9±15.7 years) participated in the experiment. We measured...

Nakao, S, Ikezoe, T, Taniguchi, M, Motomura, Y, Hirono, T, Nojiri, S, Hayashi, R, Tanaka, H, and Ichihashi, N. Effects of low-intensity torque-matched isometric training at long and short muscle lengths of the hamstrings on muscle strength and hypertrophy: A randomized controlled study. J Strength Cond Res 37(10): 1978–1984, 2023—This study investi...

Introduction: While shear modulus has been used as an index of muscle elongation, high costs prevent its general adoption. A more general indicator that can quantify muscle elongation non-invasively is needed to develop effective methods for stretching each muscle. The purpose of this study was to determine whether the echo intensity of the muscle...

Purpose This study aimed to investigate the association of muscle thickness (MT) and echo intensity (EI) obtained at different regions along the muscle length with muscle volume (MV), intramuscular adipose tissue (IntraMAT), and muscle strength of the quadriceps femoris (QF). Patients and Methods A total of 135 community-dwelling adults (64 men an...

Hamstring strain is likely to occur during the late swing phase or the first half of the stance phase in sprinting. During the late swing phase, the hamstrings and gluteus maximus (Gmax) contract eccentrically to decelerate the lower limb. We hypothesized that, when the Gmax becomes dysfunctional because of delayed onset muscle soreness (DOMS), the...

Purpose: Obtaining manual annotations to train deep learning (DL) models for auto-segmentation is often time-consuming. Uncertainty-based Bayesian active learning (BAL) is a widely-adopted method to reduce annotation efforts. Based on BAL, this study introduces a hybrid representation-enhanced sampling strategy that integrates density and diversity...

Background Muscle thickness (MT) and echo intensity (EI) measurements are ultrasound alternatives to magnetic resonance imaging (MRI) for evaluating muscle quantity and quality. The vastus medialis (VM) is a clinically important muscle, and assessment methods that most accurately reflect its quantity and quality are required. This study aimed to ex...

Rotator cuff tear is a common shoulder injury that causes shoulder dysfunction and pain. Although surgical repair is the primary treatment for rotator cuff tear, it is well recognized that impaired force exertion of muscles connecting to the involved tendon and subsequent complemental change in the force exertion of synergist muscles persist even a...

Biceps brachii muscle consists of a long head (BBL) and a short head (BBS). Shortening the BBL and BBS causes tendinopathy of the intertubercular groove and coracoid process. Therefore, it is necessary to stretch the BBL and BBS separately. This study aimed to determine the positions where the BBL and BBS were most stretched, using shear wave elast...

Purpose: We aimed to determine whether altered cartilage echo intensity is associated with knee osteoarthritis (OA) severity and whether the alteration occurs before thinning of the femoral cartilage in knee OA. Methods: The medial femoral cartilage thickness and echo intensity of 118 women aged ≥ 50 years were assessed using an ultrasound imagi...

Objective: The purposes of our study were to (1) identify muscle function-based clinical phenotypes in patients with hip osteoarthritis (OA) and (2) determine the association between those phenotypes and radiographic progression of hip OA. Design: Prospective cohort study. Setting: Clinical biomechanics laboratory of a university. Participant...

Objective: Generally, low-intensity training is recommended as selective training of the infraspinatus muscle. This study aimed to investigate whether an 8-week intervention of low-intensity, slow-movement, external rotation exercise of the shoulder led to an increase in muscle strength with shoulder external rotation and cross-sectional area (CSA...

Background The characteristics of muscle degeneration in individual quadriceps in early knee osteoarthritis (OA) and the association of muscle quantity and quality on knee dysfunction remain unclear. This study aimed to clarify the characteristics of muscle degeneration in individual quadriceps muscles in early knee OA and elucidate the association...

Background: Patellar malalignment is a risk factor of patellofemoral pain. Evaluation of the patellar alignment have mostly used magnetic resonance imaging (MRI). Ultrasound (US) is a non-invasive instrument that can quickly evaluate patellar alignment. However, the method for evaluating patellar alignment via US has not been established. This stu...

Low-intensity training at long muscle-tendon unit lengths with a greater passive force may cause muscle swelling, which may be related to hypertrophy, even if the active force production is lower than that at short muscle-tendon unit lengths. This study compared muscle swelling after low-intensity torque-matched isometric exercises at long and shor...

Purpose This study aimed to examine the effect of age on the mechanical properties, muscle size, and muscle quality in the upper and lower limb and trunk muscles. Methods We evaluated the shear modulus (G), muscle thickness (MT), and echo intensity (EI) of the upper and lower limb and trunk muscles of 83 healthy women (21–83-year-old). The G value...

Patients with knee osteoarthritis (OA) experience muscle quality loss, and is characterized by the enhanced echo intensity (EI) of the vastus medialis (VM) muscles and a high extracellular water-to-intracellular water (ECW/ICW) ratio of the thigh. This study aimed to elucidate the association between muscle degeneration and the worsening of functio...

Scapular kinematics and EMG are frequently measured as a functional assessment of the shoulder. Previous studies have compared interval averaging for these time series data, but it is not clear whether this method exactly captures the dynamics of scapular kinematics and muscle activity. Statistical parametric mapping (SPM) can be used to compare ti...

Objective: Hallux valgus, flatfoot, and rearfoot eversion are well-known major complications of knee osteoarthritis (OA). However, there is no consensus on the association between these foot malalignments and knee symptoms or function. Thus, this study aimed to examine the association between foot alignment and knee symptoms or function in patient...

This study aimed to determine the thickness and stiffness of the iliotibial band in patients with knee osteoarthritis and to identify the gait parameters that are associated with iliotibial band properties. Eighteen female patients with radiographically diagnosed medial knee osteoarthritis and knee pain (age: 69.7±5.9 years, body mass index: 23.0±3...

Background The movement of targeted subjects can be calculated using the frame subtraction method. However, the validity of this evaluation method of dynamic postural stability has not been clarified yet. This study aimed to verify the validity of the evaluation method for jump landing using the frame subtraction score based on the ground reaction...

The main objective of this study was to determine which muscle force reduction, among the vastus muscles (VAS), rectus femoris (RF), gluteus medius (Gmed), and gluteus maximus (Gmax) most significantly influenced the knee contact force. Ten young adults walked at a comfortable speed. The medial and lateral knee contact forces (KCFmed and KCFlat) we...

After publication of this article [1], the authors reported that the legend to Table 1 was incorrectly given as ’Overview of the study events for each participant during the follow-up period’, but should have been ’Demographic data for each group’ and the legend of Table 3 was incorrectly given as ‘Doses escalation during the study follow up’, but...

Introduction/aims: Attenuation of the US wave is a serious limitation of echo intensity (EI) on B-mode ultrasound (US). The aim of this study was to determine if the focus depth of US images influences the depth-dependent attenuation of EI and the relationship between EI and intramuscular adipose tissues (IntraMAT). Methods: The rectus femoris (...

Background Movement of target subjects can be calculated using the frame subtraction method. However, the validity of this evaluation method of dynamic postural stability has not been clarified yet. This study aimed to verify the validity of the evaluation method for jump landing using the frame subtraction score based on the ground reaction force...

Background: Patients with knee osteoarthritis (OA) experience muscle quality loss, and is characterized by the enhanced echo intensity (EI) of the vastus medialis (VM) muscles and a high extracellular water-to-intracellular water (ECW/ICW) ratio of the thigh. No longitudinal study has investigated the association of muscle degeneration at baseline...

Objective To examine the association of low back pain (LBP) and lumbar kyphosis with functional disabilities and knee symptoms in patients with knee osteoarthritis (OA). Methods We analyzed 586 participants (80.1% female; mean ± SD age 68.8 ± 5.2 years) from the Nagahama Study who were age ≥60 years and had radiographically confirmed knee OA. The...

Objectives To evaluate longitudinally the muscle properties of acute stroke patients and examine the association between physical activity and nutritional intake. Materials and methods This study enrolled 21 stroke patients (72.7±10.4 years). Muscle quantity (fat-free mass, appendicular skeletal muscle mass) and quality (extracellular water/intrac...

Background: A well-controlled center of mass (CoM) in a coordinated segmental manner is required during gait. A synergy index that quantifies the strength of the synergistic control of the body segments that control the CoM can be evaluated using uncontrolled manifold (UCM) analysis. Several studies have compared the synergy index between older an...

Background This study aimed to determine in how many individuals the iliocapsularis muscle (IC) could be identified on magnetic resonance imaging (MRI) and whether age and sex are associated with the cross-sectional area (CSA) of the IC. Methods Thirty-seven healthy younger adults and 40 healthy older adults were assigned to four groups: 1) 20 you...

Objectives: The concept of locomotive syndrome was proposed to highlight older adults who require nursing care services due to the malfunctioning of their locomotive organs. With the coming of a super-aging society, there is a growing need to understand relation between systemic chronic diseases and locomotive syndrome. Methods: We analyzed the...

Background/objective It is important to assess the atrophy of the rotator cuff to better understand shoulder function and pain. Previously, magnetic resonance imaging has been used for the evaluation of atrophy of rotator cuff muscles, which is time consuming. Therefore, a measurement tool requiring little time and easy accessibility is clinically...

Background: The purpose of this study was to compare the properties of the triceps surae and Achilles tendon of forefoot strike runners and non-forefoot strike runners. Methods: Fourteen male college forefoot strike runners and 11 non-forefoot strike runners participated in this study. The shear elastic moduli and cross-sectional areas of the me...

AimThis study aimed to compare motor function between sarcopenia stages with respect to sex in community-dwelling older adults.Methods The participants, comprising 2107 community-dwelling older adults (738 men and 1369 women), were classified into 4 groups and the groups were operationally defined—normal, low muscle mass, low physical function, and...

Background Deteriorated extensibility of the posterior deltoid muscle is one of the factors of posterior shoulder tightness, and improvement in its extensibility is needed. However, no study has investigated which shoulder positions effectively stretch the posterior deltoid muscle in vivo. The aim of this study was to verify the effective stretchin...

Objective Radiographic changes in knee osteoarthritis (OA) are not always associated with symptoms, especially in its early stages. Ultrasonography (US) can detect early changes in the knee joint, but the changes that reflect symptoms have not been fully elucidated. This study aimed to identify US-detectable changes in the knee that are often assoc...

Background The primary aim of this study was to investigate whether using the extracellular water/intracellular water (ECW/ICW) index and phase angle combined with segmental-bioimpedance analysis (BIA) improved the model fitting of skeletal muscle volume (SMV) estimation. The secondary aim was to compare the accuracy of segmental-BIA with that of u...

Cryotherapy is used to recover muscle damage after exercise and to treat acute sports injuries. Liquid ice (LI) can keep cold for a long time, and is assumed more effective than block ice (BI). From this, the aim of this study was to investigate the effects of LI on the change of passive stiffness (PS) as muscle function and to validate the effecti...

Background This study aimed to clarify the individual forces of each quadriceps head during low-load contractions and to determine the associations between individual muscle force and cartilage thickness and symptoms in female knee osteoarthritis patients. Methods Twenty-two women with painful knee osteoarthritis and 15 asymptomatic age-matched wo...

An amendment to this paper has been published and can be accessed via the original article.

Background Ankle plantar flexor force steadiness, assessed by measuring the fluctuation of the force around the submaximal target torque, has been associated with postural stability. Research question To investigate whether a force-matching exercise, where submaximal steady torque is maintained at the target torque, can modulate postural strategy...

Squats are frequently performed to strengthen the quadriceps (Quad) and gluteus maximus (GM) in sports and clinical fields. Since the squat itself produces a large knee contact force, clarifying the relationship between the squat techniques and the knee contact force is important. However, the influence of different squat techniques on the medial k...

Background The Japanese Orthopaedic Association (JOA) proposed the concept of locomotive syndrome (LS) in 2007 for detecting high-risk individuals with mobility limitation. In 2020, the JOA revised the clinical decision limits and introduced LS stage 3, which carried the highest-risk for LS compared to the conventional stages, 1 and 2. The purpose...

Objectives This study aimed to elucidate the association between joint line tenderness (JLT) of the knee and knee joint structural changes evaluated with ultrasonography (US) for the early diagnosis of knee osteoarthritis (KOA). Methods This cross-sectional study included 121 participants (age 71.7 ± 5.8 years, 75 women) from a community-based pop...

Objective: Patients with shoulder disorders show altered periscapular muscle activity [e.g., decreased serratus anterior (SA) and increased upper trapezius (UT) activities]. We herein devised a novel method for strengthening SA without excessive UT activation, named Squeezing Ball exercise (SB-ex) in which patients squeezed a ball between both elb...

Purpose : It is critical to determine the risk factors for activities of daily living (ADL) disability caused by locomotor dysfunction. However, no longitudinal study has investigated the association between disability due to locomotive dysfunction and multidimensional factors. Therefore, we investigated the relationship between the progression of...

Purpose Ultrasound-based prediction methods for the detection of low muscle mass for sarcopenia in older adults have been explored previously; however, the muscle that most accurately predicts it is unclear. This study aimed to clarify prediction accuracy and cut-off values for ultrasound-derived thigh and lower leg muscle thickness (MT) to detect...

This study aimed to clarify the effective stretching positions for neck extensor muscles. Fifteen healthy men were measured shear moduli of the right neck extensor muscles using ultrasound shear wave elastography in following positions: rest (Rest), flexion (Flex), contralateral bending (Bend), flexion + contralateral bending (Flex→Bend), flexion +...

This study aimed to determine the effects of simulated hip muscle weakness on changes in hip joint forces during deep squat motion. Ten healthy individuals performed squat motion at three different positions (0° foot angle [N-squat], 10° toe-in [IN-squat], and 30° toe-out [OUT-squat]). A scaled musculoskeletal model for each participant was used to...

Objectives Enhanced muscle echo intensity (EI) with ultrasound imaging and a higher extracellular water-to-intracellular water (ECW/ICW) ratio with segmental-bioelectrical impedance spectroscopy (S-BIS) represent muscle quality loss. This study aimed to clarify quadriceps muscle degeneration characteristics, focusing on muscle quality changes in pa...

Knee osteoarthritis (OA) is a major cause of knee pain, leading to physical dysfunction. External knee adduction moment (KAM), a surrogate measure of knee contact force (KCF) in the medial compartment, is related to knee pain, but the association between KCF and pain severity remains unclear. This study aimed to reveal the differences in KCF due to...

Background Changes in gait speed are required in various situations and can be achieved by changing stride length, cadence, or both. Differences in strategies for increasing gait speed may have different effects on hip joint and physical function. The purpose of this study was to determine the effects of strategies for increasing gait speed on hip...

Background Incorrect body weight shifting is a frequent cause of falls, and the control of the whole-body center of mass (CoM) by segmental coordination is essential during walking. Uncontrolled manifold (UCM) analysis is a method of examining the relation between variance in segmental coordination and CoM stability. However, no prospective cohort...

The function of the popliteus muscle [PM] is crucial to knee function. However, it remained unclear in vivo. Thus, this study aimed to explore the PM function in the non-weight-bearing and the weight-bearing conditions in vivo. Fourteen healthy subjects participated in this study. The muscle stiffness of the PM was measured using shear wave elastog...

This study aimed to examine the effect of rectus femoris (RF) elongation with passive hip angle change on the shear moduli of the vastus lateralis (VL) and medialis (VM) to verify whether Epimuscular myofascial force transmission (EMFT) occurs in the human quadriceps. Fourteen healthy men participated in this study. The shear moduli of the RF, VL,...

Pectoralis major (PMa) muscle injuries are becoming more prevalent, and their incidence differs among the PMa regions, i.e., the clavicular, sternal, and abdominal regions. Therefore, identifying the position for effectively lengthening each PMa region is critical in preventing PMa injuries. The purpose of this study was to determine the effective...

This paper proposes a computational framework for automated, landmark-free hypothesis testing of 2D contour shapes (i.e., shape outlines), and implements one realization of that framework. The proposed framework consists of point set registration, point correspondence determination, and parametric full-shape hypothesis testing. The results are calc...

Aim The present study aimed to investigate the age‐related changes in gait speeds and asymmetry during circular and straight‐line gaits among older adults aged 60–79 years. Methods The study included 391 community‐dwelling older adults aged >60 years, who participated in the Nagahama cohort study. They were assigned to four age groups: 60–64 years...

Repetitive peripheral magnetic stimulation (rPMS) is a non-invasive stimulator that can induce strong muscle contraction in selective regions. This study aimed to measure acute changes in skeletal muscle thickness induced by rPMS following a low-intensity exercise. Fifteen healthy young men performed an isometric knee extensor exercise at 30% of ma...

Objective: To compare the effects of gait trainings targeting the stance (stance training) and the swing phases (swing training) among the subjects with stroke, and quantify the characteristics in the subjects who benefitted from either the stance training or the swing training. Methods: Sixteen subjects with stroke performed the stance training...

Increased muscle stiffness of the pectoralis minor (PMi) could deteriorate shoulder function. Stretching is useful for maintaining and improving muscle stiffness in rehabilitation and sport practice. However, the acute and prolonged effect of stretching on the PMi muscle stiffness is unclear due to limited methodology for assessing individual muscl...

Numerous muscles around the shoulder joint are required to work in a coordinated manner, even when a basic shoulder movement is executed. Muscle synergy can be utilized as an index to determine muscle coordination. The purpose of the present study was to investigate the muscle coordination among different shoulder muscles underlying basic shoulder...

An increase in the stiffness of the coracobrachialis muscle can restrain proper movement of the glenohumeral joint and scapula during arm elevation. Therefore, muscle stiffness should be reduced through stretching. The aim of this study was to determine the effective stretching position of the coracobrachialis muscle using ultrasound shear wave ela...

Purpose: The primary purpose of this study was to clarify the occurrence of sites of edematous changes using the measured circumferences of the thigh and lower leg via three-dimensional (3D) body scanning. The secondary purpose was to determine the relationship between the volume changes using 3D body scanning and the resistance changes as indicato...

Background Force steadiness is evaluated as force variability during constant force exertion around a target level. Ankle plantar flexor force steadiness is reported to be related to postural sway on an unstable platform in healthy young adults; however, this relationship in older adults is unclear. Research question This study aimed to investigat...