Kenji Murata

Saitama Prefectural University · Department of Physical Therapy

Accumulation of senescent neurons in the dorsal root ganglion (DRG) is an important tissue phenotype that causes age-related degeneration of peripheral sensory nerves. Senescent neurons are neurons with arrested cell cycle that have undergone cellular senescence but remain in the tissue and play various biological roles. To understand the accumulat...

Background Chronic ankle instability (CAI) is a clinical sequela that causes the recurrence of ankle sprain by inducing ankle sensorimotor dysfunction. Animal models of CAI have recently shown that ankle ligament injuries mimicking an ankle sprain result in chronic loss of ankle sensorimotor function. However, the underlying mechanisms determining...

Anterior cruciate ligament (ACL) injuries have a very low healing capacity but have recently been shown to heal spontaneously with conservative treatment. This study examined the mechanism of spontaneous ACL healing by focusing on the intra-articular tissues of the knee joint. Skeletally mature Wistar rats ( n = 70) were randomly assigned to two gr...

Introduction Joint instability is a common finding of clinical importance in patients with knee disease. This literature review aimed to examine the evidence regarding the effect of orthosis management on joint instability in knee joint disease. Methods The detailed protocol for this study was published in the International Prospective Register of...

Background Although the importance of kinematic evaluation of the sit-to-stand (STS) test of total knee arthroplasty (TKA) patients is clear, there have been no reports analyzing STS during the 30-s chair sit-up test (30 s-CST) with a focus on kinematic characteristics. This study aimed to demonstrate the clinical utility of kinematic analysis of S...

Objective: We previously reported how treadmill exercise can suppress cartilage degeneration. Here, we examined the changes in macrophage dynamics in knee osteoarthritis (OA) during treadmill exercise and the effect of macrophage depletion. Design: OA mouse model, generated via anterior cruciate ligament transection (ACLT), was subjected to trea...

Aims Joint instability is associated with various joint conditions including osteoarthritis (OA) and inflammation, and we have developed model which is determined to role of knee instability. Investigating cartilage maintenance factors such as hyaluronic acid (HA) and glycosaminoglycans (GAGs) can provide insights into the effect of the mechanical...

Design: Systematic review using PRISMA guidelines. Purpose: To explore Relationship between ankle instability and ankle sprain recurrence in preventing recurrence of ankle sprains and to provide appropriate treatment. Methods: MEDLINE (the Cochrane Library) and the Physiotherapy Evidence Database (PEDro) were explored using key words related t...

Background Although the importance of kinematic evaluation of the sit-to-stand (STS) test of total knee arthroplasty (TKA) patients is clear, there have been no reports analyzing STS during the 30-second chair sit-up test (30s-CST) with a focus on kinematic characteristics. This study aimed to demonstrate the clinical utility of kinematic analysis...

Purpose Joint instability is a common joint dysfunction and a cause of musculoskeletal disorder and pain after anterior cruciate ligament injury and osteoarthritis. The aim of this literature review is to review the existing evidence regarding the impacts of knee brace in persons with joint instability, or laxity after knee disease concerning physi...

Introduction: Muscle weakness rotator cuff tear (RCT) after is the most important factor for physical function. However, the mechanism underlying muscle atrophy and treatment after rotator cuff injury remains to be elucidated. This study sought to systematically review published animal studies to explore effective treatment options for muscle weakn...

Entheses, which are tendon‐to‐bone attachment sites in the musculoskeletal system, play important roles in optimizing the mechanical stress and force transmitted from the muscle to the bone. Sports‐related enthesopathy shows pathological features, including hyperplasia of the fibrocartilage (FC) region in the enthesis. The amount of exercise and ty...

Introduction/aims: Motor function recovery is frequently poor after peripheral nerve injury. The effect of different numbers of nerve crushes and exercise on motor function recovery is unknown. We aimed to examine how different numbers of crushes of the rat sciatic nerve affects muscle reinnervation and plasticity of spinal circuits and the effect...

Objective Joint instability and meniscal dysfunction contribute to the onset and progression of knee osteoarthritis (OA). In the destabilization of the medial meniscus (DMM) model, secondary OA occurs due to the rotational instability and increases compressive stress resulting from the meniscal dysfunction. We created a new controlled abnormal tibi...

Mechanical stress is involved in the onset of sports-related enthesopathy. Although the amount of exercise undertaken is a recognized problem during disease onset, changes in muscle contraction type are also involved in the increase in mechanical stress during exercise. This study aimed to clarify the effects of increased mechanical stress associat...

Objective Moderate mechanical stress is necessary for preserving the cartilage. The clinician empirically understands that prescribing only exercise will progress osteoarthritis (OA) for knee OA patients with abnormal joint movement. When prescribing exercise for OA, we hypothesized that degeneration of articular cartilage could be further prevente...

Objective It has been debated whether the onset of knee osteoarthritis is initiated in cartilage or subchondral bone. The purpose of this study was to clarify the effects of increasing or decreasing joint instability on cartilage degeneration and subchondral bone changes in knee OA by comparing different models of joint instability. Design We used...

Objective The effect of the type of mechanical stress on OA onset has not been clarified. The aim of this study was to establish a new model that reproduces the type and increase and decrease of mechanical stress in vivo and to clarify the differences in the mechanism of knee OA onset and progression among the models. Design To reproduce the diffe...

Objective Joint instability and meniscal dysfunction contribute to the onset and progression of knee osteoarthritis (OA). In the destabilization of the medial meniscus (DMM) model, secondary OA occurs due to the rotational instability and increases compressive stress resulting from the meniscal dysfunction. We created a new controlled abnormal tibi...

How various types of muscle contraction during exercises affect bone formation remains unclear. This study aimed to determine how exercises with different muscle contraction types affect bone morphology. In total, 20 mice were used and divided into four groups: Control, Level, Down Slow, and Down. Different types of muscle contraction were induced...

Aim: The healing ability of the anterior cruciate ligament (ACL) injury is very poor; however, it has recently been shown to undergo self-healing with conservative treatments. In this study, we evaluated the influence of the site of injury on the healing process after complete transverse tear of ACL using a rat model. Materials and Methods: A total...

Objective Abnormal load stress caused by joint instability has been reported to be one of the factors responsible for the development of osteoarthritis (OA). However, few studies have investigated the efficacy of exercise therapy for patients with knee instability-induced OA, and there are no specific treatment guidelines or effects for this form o...

Objective: Abnormal joint movement is associated with osteoarthritis (OA). Previous studies using the controlling abnormal joint movement (CAJM) model of OA reported delayed cartilage degeneration; however, none of them focused on gait performance and the localization of matrix metalloproteinase 13 (MMP13) and tissue inhibitor of metalloproteinase...

Background Anterior cruciate ligament (ACL) injury is one of the most common injuries of the knee joint and is becoming more prevalent. While ACL reconstruction is considered the “gold standard” of treatment, some studies have demonstrated natural spontaneous healing of the ACL in humans, rabbits, and rats. At this time, the mechanism of ACL healin...

Patients with critical limb ischemia（CLI）for whom the minimally invasive technique was used for tendon Achilles lengthening（MIT-TAL）were examined. They had a limited dorsiflexion range of motion and risk of ulcer development. In total, seven patients（five males, two females）underwent MIT-TAL. Plantar forefoot ulceration, dorsiflexion range of motio...

Objective: Abnormal joint instability contributes to cartilage damage and osteophyte formation. We investigated whether controlling joint instability inhibited chronic synovial membrane inflammation and delayed osteophyte formation and examined the role of transforming growth factor-beta (TGF-β) signaling in the associated mechanism. Design: Rat...

Neurotrophins play a crucial role in neuroplasticity, neurogenesis, and neuroprotection in the central nervous system. Aerobic exercise is known to increase the expression of brain‐derived neurotrophic factor (BDNF) in the hippocampus. The objective of this study was to investigate the effects of aging and moderate exercise on cognitive function an...

Objective Osteoarthritis (OA) is induced by accumulated mechanical stress to joints; however, little has been reported regarding the cause among detailed mechanical stress on cartilage degeneration. This study investigated the influence of the control of abnormal joint movement induced by anterior cruciate ligament (ACL) injury in the articular car...

We developed a novel controlled abnormal joint movement (CAJM) model that controls instability after traditional anterior cruciate ligament transection (ACL-T). We evaluated whether joint instability damping suppresses synovial inflammation in osteoarthritis patients using our new CAJM rat model. We found that joint instability in rats differed bet...

Introduction/Background Cells communicate with extracellular matrix (ECM) through the some essential components of mechano-biological factors. Integrin and fibronectin are known as a connecting organizer between ECM and the cells. Moreover, these are also known as a sensor of mechanical cues. In this study, we focus the function of this sensor of m...

Introduction/Background Low intensity exercise following peripheral nerve injury promotes nerve regeneration, whereas high intensity exercise has a negative effect. Our study aimed to assess the influence of low intensity exercise on the expression of proteins related to cell death regulation and axonal regrowth. Material and method The sciatic ne...

Introduction/Background The anterior cruciate ligament injury make difficulties in daily activity of daily living and sports. Even when the knee joint is operated a ligament reconstruction after injury, some patients complain of joint instability. It is thought that the nerve existing there is damaged when the ACL is damaged, and the nerve function...

Introduction/Background In osteoarthritis of the knee, recognition of pain pathophysiology and effective exercise therapy is an important issue for establishing effective treatment methods. Both animals and humans, the increase in mechanical stress due to joint instability induces joint deformity and pain. Improvement in joint instability may be ef...

Introduction/Background Controlling abnormal joint movement immediately after anterior cruciate ligament (ACL) injury could prevent destruction of intra-articular tissues and lead to spontaneous ACL healing. In a previous study, healing tissue was observed between the remnant gaps in the process of spontaneous ACL healing. The purpose of this study...

Aerobic exercise is known to increase expression of neurotrophins, particularly brain-derived neurotrophic factor (BDNF), in the hippocampus and to improve cognitive function. Exercise exerts neuroprotective effects in the hippocampus by inducing epigenetic changes, which play crucial roles in aging and neurodegenerative diseases. Specifically, the...

Objective Osteoarthritis is a common consequence of anterior cruciate ligament (ACL) injury. Joint instability induced by ACL transection is involved in the chondrocyte response in the articular cartilage degeneration process. The aim of this study was to confirm the effect of controlling joint instability after ACL injury by investigating the chon...

Anterior cruciate ligament (ACL) injuries are known to have very low rates of spontaneous healing. There have been several studies since the mid-1960s concerning the approaches to accelerate spontaneous healing of ACL injuries. Recent studies have identified similarities in the healing response of ACL and other extra-articular ligaments, in terms o...

Objective: Joint instability induced by anterior cruciate ligament (ACL) transection is commonly considered as a predisposing factor for osteoarthritis of the knee; however, the influence of re-stabilization on the protection of articular cartilage is unclear. The aim of this study was to evaluate the effect of joint re-stabilization on articular...

Background: The poor healing capacity of a completely ruptured anterior cruciate ligament (ACL) has been attributed to an insufficient vascular supply, cellular metabolism, and deficient premature scaffold formation because of the unique intra-articular environment. However, previous studies have focused on intra-articular factors without consider...

The objective of this study was to investigate the effects of aging and moderate exercise on the expression of neurotrophin and glutamate receptors in the hippocampus using senescence‐accelerated mouse P1 (SAMP1) and its age‐matched control mouse (SAMR1). The mice were assigned to four groups (SAMP1‐sedentary, SAMP1‐exercise, SAMR1‐sedentary and SA...

Rotator cuff tears are a common injury in the elderly and often impose limitations on the range of motion and cause pain. The cause of rotator cuff tearing is unknown, and degeneration of the supraspinatus tendon with age is poorly understood.In the present study, we examined collagen degeneration of the supraspinatus tendon in the rat shoulder joi...

Proprioceptive training is highly common in rehabilitation of aged people to prevent injures or to enhance performance. This study aimed at determining whether the exercise on a moving platform induces changes in neurotrophins expression patterns in the lumber spinal cord of aged rats. Twelve aged male rats (2 years old) and ten adult male rats (10...

The objective of this study was to investigate the effects of aging and low‐load balance exercise on the expression of neurotrophins and glutamate receptors in some brain regions including motor cortex, cerebellar cortex and hippocampus using senescence‐accelerated mice. The mice were assigned to four groups (adult‐control, adult‐exercise, aged‐con...

Objective Tendinopathy is a common clinical problem at the shoulder joint. Aging leads to the degeneration the supraspinatus tendon, On the other hand, the exercise is vital to the tendon remodeling. In this present study, we observed the effect of periodic exercise using supraspinatus tendon of aged rat. Methods We studied 2‐years‐old male Wister...