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Purpose To identify the effect of a 52-weeks gait training program with an exoskeletal body-powered gait orthosis on the body composition of paraplegics. Patients and Methods Ten subjects with spinal cord injury at the thoracolumbar spine level for more than 2 years participated and were divided into exercise (n=5) and nonexercise (n=5) groups. A gait training program comprising stages 1-6 with customized exoskeletal body-powered gait orthosis was conducted for 52-weeks. A six-stage gait training program was conducted to manage the body composition and prevent obesity, and the changes in the body composition before and after the program were determined through bioelectrical impedance analysis. Results No significant changes in weight, fat-free mass (kg), lean body mass (kg), and percent fat mass (%) are seen in the exercise group before and after the 52-weeks program. However, fat-free mass (pre = 47.3± 6.5, post = 44.3 ± 5.4, kg), lean body mass (pre = 45.2 ± 6.3, post = 42.3±5.2, kg), and percent fat mass (pre = 30.1 ± 12.1, post = 40.9 ± 9.1, kg) show significant changes (p < 0.05) in the nonexercise group. In the nonexercise group, among lean body mass changes over 52-weeks in the upper limbs (-31%), trunks (-9.7%), and lower limbs (-8.6%), upper limbs exhibit the most significant decrease (p < 0.05). Conclusion The gait training program with exoskeletal body-powered gait orthosis has a positive effect on fat management in the whole body and lean body mass loss in paraplegics. Furthermore, it is effective in preventing continuous muscle loss and in maintaining health by reducing body fat. Body composition measurements with bioelectrical impedance analysis for paraplegics can be applied in various clinical areas and can be combined with various arbitration methods such as rehabilitation program.

In order to calculate the continuous relative phase (CRP) between joints, the portrait method based on the joint angle and angular velocity and the Hilbert transform method based on the analytical signal have been widely used. However, there are few comparisons of these methods. Therefore, the aim of this study is to quantitatively compare these methods by calculating the CRP in the lower-limb joints of the elderly during level free walking. Eighteen elderly female adults ([Formula: see text] year-old, [Formula: see text][Formula: see text]cm, [Formula: see text][Formula: see text]kg) wearing a Helen Hayes full-body marker set walked 10[Formula: see text]m on level ground at a self-selected velocity. The angles of the hip, knee, and ankle were measured. To calculate the CRP using the portrait method, the angular velocities were measured. Then, the phases between the angle and the angular velocity were calculated. To calculate the CRP using the Hilbert transform method, analytical signals were acquired. Then, the phases between the real and imaginary parts were calculated. A CRP was calculated as the difference between the phase in the proximal joint and the phase in the distal joint. To evaluate the similarity in the shape between the portrait and Hilbert transform methods, the cross-correlation was calculated. Bland–Altman plot analyses were performed to assess the agreement between these methods. For the root mean squares (RMSs) and standard deviations (SDs), a paired [Formula: see text]-test and the Pearson correlation between methods were evaluated. There were similarities in the in-phase or out-of-phase features and in the RMS and SD between the methods. Additionally, a higher cross-correlation and agreement between them were found. These results indicated the similarity between the portrait and Hilbert transform methods for the calculation of the CRP. Therefore, either method can be used to evaluate joint coordination.

Purpose To identify the effect of a 52-weeks gait training program with an exoskeletal body-powered gait orthosis on the body composition of paraplegics. Patients and Methods Ten subjects with spinal cord injury at the thoracolumbar spine level for more than 2 years participated and were divided into exercise (n=5) and nonexercise (n=5) groups. A gait training program comprising stages 1–6 with customized exoskeletal body-powered gait orthosis was conducted for 52-weeks. A six-stage gait training program was conducted to manage the body composition and prevent obesity, and the changes in the body composition before and after the program were determined through bioelectrical impedance analysis. Results No significant changes in weight, fat-free mass (kg), lean body mass (kg), and percent fat mass (%) are seen in the exercise group before and after the 52-weeks program. However, fat-free mass (pre = 47.3± 6.5, post = 44.3 ± 5.4, kg), lean body mass (pre = 45.2 ± 6.3, post = 42.3±5.2, kg), and percent fat mass (pre = 30.1 ± 12.1, post = 40.9 ± 9.1, kg) show significant changes (p < 0.05) in the nonexercise group. In the nonexercise group, among lean body mass changes over 52-weeks in the upper limbs (−31%), trunks (−9.7%), and lower limbs (−8.6%), upper limbs exhibit the most significant decrease (p < 0.05). Conclusion The gait training program with exoskeletal body-powered gait orthosis has a positive effect on fat management in the whole body and lean body mass loss in paraplegics. Furthermore, it is effective in preventing continuous muscle loss and in maintaining health by reducing body fat. Body composition measurements with bioelectrical impedance analysis for paraplegics can be applied in various clinical areas and can be combined with various arbitration methods such as rehabilitation program.

The aim of this study was to develop and validate a sensor to measure interfacial shear forces on the residual limb in the socket of lower-extremity amputees. The sensor consisted of three layers: upper and lower layers made from aluminum, and a middle layer made from polyvinyl chloride. One strain gauge was placed in the middle layer with an elastomer to overcome the nonlinear response properties. In a clinical application, a male transtibial amputee (42 years old, 82 kg, 182 cm) was asked to walk on level ground and on a 5° slope. The interfacial shear force on the stump/socket on the medial and lateral distal residual limb was measured. The shear sensor (28 mm × 16 mm × 3.5 mm), which was validated using weights, showed high linearity and sensitivity (measurement range: –10 to 10 N). A shear force was exerted on the residual limb throughout a gait. Additionally, the vertical shear forces were found to depend on the ground while the horizontal shear forces depended on the prosthetic socket site. In conclusion, a shear sensor of comparable volume may be useful for measuring the interfacial shear force on the stump/socket in lower-extremity amputees.

Measuring the muscle properties of patients with spinal cord injuries (SCIs) is important to better understand their biomechanical features. In this study, we sought to evaluate the between-day reliability of MyotonPRO, a handheld device that can measure muscle mechanical properties, and assess whether it is reliable to measure muscle properties over time in patients with SCI. Thirteen men with complete SCIs (age 53.9 ± 6.3 years, height 171.0 ± 5.2 cm, weight 66.1 ± 5.8 kg), and injury levels ranging from L1 to T12, were enrolled. Oscillation frequency; logarithmic decrement; dynamic stiffness; mechanical stress relaxation time; and creep of the biceps femoris, medial and lateral gastrocnemius, rectus femoris, tibialis anterior, and Achilles tendon were measured on consecutive days using MyotonPRO. The intraclass coefficient for most muscles and the Achilles tendon ranged from 0.53 to 0.99 for all parameters. The percentage standard error of the measurement for many parameters in most muscles and the Achilles tendon was less than 10%. Bland-Altman analysis showed a high agreement for all mechanical properties. No significant differences were observed in any muscle or Achilles tendon properties between days (all p > 0.05). These results indicate that the MyotonPRO is reliable for between-day measurements of the mechanical properties of lower limb muscles and Achilles tendon in patients with SCI.

AHNAK has been reported to be involved in actin cytoskeleton rearrangement of some cell types, calcium homeostasis, and activation of T cells. Although the functional role of AHNAK in muscle cells, epidermis, and brain has been determined, its association with apparent clinical impairment has not been found yet. During phenotypic analysis of AHNAK knock out (KO) mice for many years, we observed that AHNAK KO mice showed very slow growth. Snouts of these animals were very short, and their bones were easily broken compared to normal mice. It is known that AHNAK is closely related to calcium. However, intensive morphological studies on phenotypes of bone have yet been reported for AHNAK. Thus, the objective of the present study was to analyze the morphology of skull, mandibular, limbs, and caudal bones of AHNAK KO mice intensively using micro-CT with many factors for various ages of these mice (6 weeks, 18 weeks, and 40 weeks). As a result, it was found that the facial region of AHNAK KO mouse showed a large difference in mandible than skull. Their both femur and tibia were shortened, and bone strength was also significantly decreased compared to normal mice. Particularly, the tail bone of AHNAK KO mice exhibited morphological abnormality by age. Taken together, these results suggest that AHNAK plays an important role in bone shape, development, and metabolism. Although our results demonstrated that AHNAK has a distinct role in bone, further investigations are needed to determine various features of bone metabolism related to AHNAK in the future.

Gait and mobility in patients with gait impairment are important in maintaining and improving their physical and psychological health and to return to society. Thus, the aims of the current study were to develop and evaluate a new wearable exoskeleton for gait rehabilitation assistance integrated with a mobility system (RehabWheel) for patients with gait impairment. A wearable exoskeleton was controlled by artificial pneumatic muscles to mimic joint movement; appropriate gait training was then undertaken. In total, 13 healthy males participated in evaluating RehabWheel by comparing joint angle kinematics and muscle activation patterns during walking over ground with RehabWheel and normal gaits. The joint angle kinematics of the hip and knee joints with RehabWheel were similar to those of normal gait despite differences in their magnitude. Additionally, muscle activations in the hip and knee joints were less during RehabWheel gait than normal gait and were associated with joint kinematics. These findings indicate that RehabWheel may have potential for incorporation into gait rehabilitative training assistance combined with a wheelchair platform for movement. This study is valuable for the initial identification of the practical feasibility of this new mobility system with both mobility and gait rehabilitation functions.

This study aimed to evaluate the kinematics and kinetics of the lower limb in both the intact and amputated leg in individuals with transtibial amputations wearing Energy storage and return feet (ESRFs) with fixed ankles and Prosthetic feet with adaptive ankles (PFAAs) during level walking. Three individuals with transtibial amputations walked on level ground wearing their own ESRFs and PFAAs. Spatiotemporal parameters, kinematics, and kinetics of the lower-extremity joints were measured in the amputated and intact legs. There were differences in the kinematics of the joints in the amputated leg and of the ankle in the intact leg between ESRFs and PFAAs. Differences in joint moments, power, and stiffness in most joints in both legs and braking impulse were found between ESRFs and PFAAs. Thus, although it was a pilot study with three subjects, ankle angle control mechanisms (ESRFs: Fixed ankle vs. propriofoot: Mechanical motor vs. elan and echelon: Hydraulic actuator) might affect biomechanical features during level walking.

This study aimed to develop a sensory feedback system which could measure force and temperature for the user of myoelectric prosthetic hands. The Sensory measurement module consisted of a force sensing resistor to measure forces and non-contact infrared temperature sensor. These sensors were attached on the fingertips of the myoelectric prosthetic hand. The module was validated by using standard weights corresponding to external force and a Peltier module. Sensory transmission module consisted of four vibration motors. Eight vibration patterns were generated by combining motion of each vibration motor and were dependent on kinds and/or magnitude. The module was verified by using standard weigts and water at varying temperatures. There were correlations of force and temperature between the sensory measurement module and standard weight and water. Additionally, exact vibration patterns were generated, indicating the efficacy of the sensory feedback system for the myoelectric prosthetic hand.

Little information is available about the characteristics in the turning gait of hemiplegic elderly, which occurs frequently in daily life. It is also difficult to examine the altered characteristics due purely to hemiplegia because of no consideration of aging-related factors. The aim of this study was to identify the altered characteristics of relative muscle activation in both straight and turning gaits together due to hemiplegia, through comparing healthy and hemiplegic elderly. Six healthy elderly and six hemiplegic elderly were participated. The center of body mass (COM) and the lower extremity joint angles were measured during straight and turning gaits at self-selected speed, using a motion capture system. A surface wireless electromyogram (EMG) system was used together to identify muscle contributions. Mediolateral (ML) sways of upper-body in hemiplegic elderly were ~174% for straight gait and ~26% for turning gait. Lower extremity joint angles in hemiplegic elderly were generally reduced by ~60-70% for both gaits. Muscle co-activation and relative muscle contributions were generally altered at all phases in hemiplegic elderly, but the patterns were different between straight and turning gaits. This study confirmed that the ML sways of hemiplegic elderly moved towards the non-paretic side more and joint angles showed large decreases. Muscles acted with different contributions, depending on the gait.

A problem related to musculoskeletal function degeneration may be occurred in patients who experience gait disorders if they use wheelchair-based mobility assistive system only with no gait exercise for long periods of time. Therefore, in current study, we aimed to suggest a new concept of a mobility system that integrates a wheelchair platform, used for the implementation of mobility, and a wearable exoskeleton structure, used for the implementation of gait assistance, and to validate its structural stability and gait control confidence. A new system was designed and manufactured and its structural stability and gait control confidence were validated. The basic structure of the system was designed based on the platform of a wheelchair for the implementation of mobility, and incorporated a wearable exoskeleton structure formed with six one-degree-of-freedom (DoF) rotational joints for implementing the function of gait assistance. In the case of the wearable exoskeleton part, 12 pneumatic artificial muscles were attached for the 1-DoF flexion-extension operation of the hip, knee, and ankle joints. The results showed that the structural stability of the system was sufficient and the control operation of the system accurately simulated the joint angle change patterns that occur during general normal gait, within an error range of 2.6 ± 10.8%. Our new system suggested may potentially be applicable for gait assistive function incorporated with a wheelchair platform for movement. This study may be valuable because it initially suggest a new concept of the wheelchairtype mobility assistive system with gait assistive function.

This study is to investigate the synchronous phenomena between bone quality and longitudinal length in a same subject affected by landing exercise. Physical exercise on the ground induces external loading to human body due to resistance from ground which can activate bone generation or remodeling. Especially, when the impact stimulation is applied to bone, it may improve bone quality and lengthening. 6-week-old male Wistar rats were randomly allocated to one of two conditions: free fall from 40 cm-height (I40; n = 7), and control (IC; n = 7). The impact stimulations were administered to the free fall groups, 10 times/day, and 5 days/week for 8 weeks. Structural parameters and longitudinal length of tibia were measured to quantitatively evaluate the variation in morphological characteristics and bone length with maturing. The landing impact seems to be commonly effective on the enhancement of bone quality as well as longitudinal growth. However, the extent of enhancement may be more dominant in bone quality than longitudinal growth. On the other hand, the ratio of longitudinal growth seems to be dependent on the duration of stimuli whereas the enhancement of bone quality does not. This study verified that free-falls exercise can be effective on the enhancement of bone qualities and promotion of vertical growth in long bones. We expect that it might be possible for the moderate impact stimulation to be proposed as an aid for prevention of bone loss and promotion of bone lengthening.

A human's center of mass (COM) is a widely used parameter in both clinical and practical applications. The segmental analysis method for determining the COM is considered the gold standard but is difficult to apply in a real environment.The purpose of this study was to confirm the efficacy of an alternative COM determination method-the sacral marker method-by comparing segmental analysis and sacral marker method results in three dimensions during level or slope walking.Ten healthy young subjects (age = 24.0 ± 4.5 yr, height = 174.5 ± 5.9 cm, and weight = 66.9 ± 9.4 kg) participated in the study. Each participant was monitored using a Helen Hayes full-body marker set and asked to walk on level and sloped (7°) terrain. The markers' trajectories were subsequently recorded. Each participant's COM was determined using segmental analysis and sacral marker methods via calculation and direct measurement, respectively.Comparative results indicated no significant differences (p 0.05) between the segmental analysis and sacral marker method results for the COM displacement, velocity, or acceleration in the fore-aft and vertical directions. Conversely, significant differences (p 0.05) between the two methods were observed for the COM displacement and acceleration in the medial-lateral direction, suggesting kinematic differences.Based on this latter finding, caution should be exercised when determining COM kinematics using the sacral marker method.

The aim of this study was to evaluate the influence of balance on the spatiotemporal features, lower-limb kinematics, and center of mass (COM) of the non-faller elderly during walking. In this study, 20 healthy elderly women (age, 76.2 ± 5.6 years; height, 150.1 ± 3.2 cm; weight, 55.8 ± 9.0 kg) were enrolled. Based on the Berg balance scale (BBS), the elderly were classified into two groups: poor balance (PB; BBS scores 0.05). The ROM of the mediolateral COM was greater in PB than in GB. Hip transversal movements in the two groups were different. The impairment of the lateral balance function might contribute to an increase in the incidence of fall events in the elderly with poor balance.

Background Management of a knee contracture is important for regaining gait ability in transtibial amputees. However, there has been little study of prosthesis training for enhancing mobility and improving range of motion in cases of restricted knee extension. Objective This study aimed to evaluate the effects of adaptive training for an assist device (ATAD) for a transtibial amputee with a knee flexion contracture (KFC). A male transtibial amputee with KFC performed 4 months of ATAD with a multidisciplinary team. During the ATAD, the passive range of motion (PROM) in the knee, amputee mobility predictor (AMP) assessment, center of pressure (COP) on a force plate-equipped treadmill, gait features determined by three-dimensional motion analysis, and Short-Form 36 Item Health Survey (SF-36) scores were evaluated. Results Following ATAD, PROM showed immediate improvement (135.6 ± 2.4° at baseline, 142.5 ± 1.7° at Step 1, 152.1 ± 1.8° at Step 2, 165.8 ± 1.9° at Step 3, and 166.0 ± 1.4° at Step 4); this was followed by an enhanced COP. Gradually, gait features also improved. Additionally, the AMP score (5 at baseline to 29 at Step 4) and K-level (K0 at baseline to K3 at Step 4) increased after ATAD. Along with these improvements, the SF-36 score also improved. Conclusions ATAD could be beneficial for transtibial amputees by relieving knee contractures and improving gait.

Seat comfort is one of the main factors that consumers consider when purchasing a car. In this study, we develop a dummy with a shear-force sensor to evaluate seat comfort. The sensor has dimensions of 25 mm × 25 mm × 26 mm and is made of S45C. Electroless nickel plating is employed to coat its surface in order to prevent corrosion and oxidation. The proposed sensor is validated using a qualified load cell and shows high accuracy and precision (measurement range: −30–30 N; sensitivity: 0.1 N; linear relationship: R = 0.999; transverse sensitivity

This study aimed to investigate kinetics and kinematics of the ankle joint during level ground, ramp, and stair ambulations using different types of adaptive ankle feet (AAFs), Proprio-FootTM (Ossur, IcEland), elan foot (Endolite, USA), and Echelon foot (Endolite, USA). A transtibial amputee was asked to walk on a level ground, a ramp with a 7° slope, and a stair of height 15 cm. The ankle angle and symmetry index (SI) based on the symmetry of the external work performed were measured for AAFs and ambulation. The single support time and stance phase during ambulation were higher for AAFs than the fixed ankle foot. During level ambulation, dorsiflexion increased for all AAFs. During slope ascent ambulation, dorsiflexion increased for the elan foot and Proprio-Foot™, as well as during the swing phase of the Echelon foot. During slope descent ambulation, the maximum dorsiflexion decreased for the Proprio-Foot™. During stair ascent, the elanElan foot and Proprio-Foot™ feet improved the dorsiflexion. During stair descent, all AAFs improved the dorsiflextion. Furthermore, SI increased for most of the adaptive ankle feet for all terrain conditions. These results indicate that AAFs can be used to improve the kinetics and kinematics of the ankle on the involved side.

Sciatic nerve injury (SNI) can lead to significant bone loss in the lower extremities. However, the effects of SNI on the lumbar vertebrae are controversial. The present study aimed to evaluate the longitudinal effects of SNI on the lumbar vertebrae. Twenty-four 12-week-old male C57BL/6 mice (24.55±0.17 g) were randomly assigned to 3 groups (8 mice each) and underwent unilateral sciatic neurectomy (USN group), bilateral sciatic neurectomy (BSN group), or no surgery (CON group). The third (L3) and fourth (L4) lumbar vertebrae were scanned by in-vivo micro-computed tomography (iCT) preoperatively and at 14 and 28 days postoperatively. Using μCT images, structural parameters and bone mineralization density distribution of the trabecular bone were analyzed among the 3 groups. In the BSN group, structural and material properties of L3 and L4 worsened after 14 days. Deterioration in the structural properties of L3 was observed at 28 days in the USN group, whereas no changes were observed in L4. These results implied that SNI can cause considerable deterioration in the microarchitecture of trabecular bone in the lumbar vertebrae. However, differences in the magnitude and rate of the deterioration and its onset period are observed between cases of unilateral and bilateral SNI.

Chang-Yong Ko,* Sol-Bi Kim,* Hyuk-Jae Choi, Yunhee Chang, Sungjae Kang, Yoon Heo, Jeicheong Ryu, Gyoosuk Kim, Museong Mun Korea Orthopedics and Rehabilitation Research Center, Incheon, South Korea *These authors contributed equally to this work Background: Patients with hand and/or wrist pathology are recommended to have a four-wheeled walker with an arm rest (FWW-AR) rather than a standard walker or a standard four-wheeled walker (FWW). However, only a few quantitative studies have been performed to compare upper and lower extremity weight bearing. The aim of this study was to evaluate forearm and foot weight bearing using a FWW-AR and the effect of the armrest height.Methods: Eleven elderly women (mean age 80.1±5.3 years; mean height 148.5±4.0 cm; mean weight 51.2±9.0 kg) were enrolled. The subjects walked with an FWW-AR, with the elbow in either 90 degree (D90) or 130 degree (D130) flexion, for a distance of 10 m. Surface electromyographic signals were recorded for the upper, middle, and lower trapezius, anterior deltoid, and erector spinae muscles; walking velocity was measured with the subjects weight bearing on their feet and forearms while walking. Simultaneously, the maximum plantar and forearm loads during walking with an FWW-AR were measured.Results: The normalized foot plantar loads were lower at D90 than at D130, while the normalized forearm load was higher at D90 than at D130 (all P

Aim Numerous elderly individuals use the four-wheeled walker (FWW) as a gait-assistive device. The walker's handgrip height is important for correct use. However, few clinical studies have investigated the biomechanical effects of the FWW's handgrip height on balance. Therefore, the present study assessed kinematic features of the gait, torso and pelvis during use of the FWW at two levels of handgrip height (48% vs 55% of the subject's height) while assessing balance in older adults. Methods A total of 20 older adults were allocated into two groups according to the Berg Balance Scale (BBS): good balance (GB; BBS ≥46) versus poor balance (PB; BBS

The aim of this study was to determine whether gait training using powered gait orthosis (PGO) improved gait function in paraplegics following spinal cord injury (SCI) and whether it suppressed related complications. Three complete SCI patients were used as case studies and put through four months of the gait training. The parameters of gait function—namely, velocity, step length, and cadence—were evaluated by three-dimensional motion analysis. The body fat mass (BFM) and the bone mineral density (BMD) of the femur were also measured. Velocity, cadence and step length were observed to significantly improve (p = 0.026, 0.039, 0.013, respectively) after four months of PGO gait training; furthermore, there were increments in all the subjects. BFM also significantly decreased (p = 0.004), but there was no significant change in body weight (p = 0.072), although a decrease was observed in all the subjects. Moreover, no significant change in BMD was observed (p = 0.221), although there was an increment in all the subjects. These results showed that gait training using PGO contributed to not only improving gait function in SCI patients but also suppressing increase in body fat mass and bone loss.

Objective: The aim of this study is to investigate the gender-differences in vibrotactile responses(sensitivity and displeasure) of residual forearm simulated by vibration stimulation in upper limb(trans-radial) amputees. Background: Several studies have reported that vibration stimulation using the haptic vibrator is one the most effective methods for delivering sensation to an amputees. However, few studies have reported the perception to haptic vibratory stimulus, particularly sensitivity and displeasure. Method: We set up a custom-made vibration stimulation system that included 6 actuators(3 medial parts and 3 lateral parts) and a graphical user interface(GUI)-based acquisition system to investigate changes in residual somatosensory sensibility and displeasure in the forearm of upper limb(trans-radial) amputees. Vibration actuators were attached at the 25%-point on the proximal forearm. Stimulation with 32Hz, 64Hz, or 149Hz of frequency was used for the sensitivity tests and with 32~257Hz of frequency was used for the discomfort experiments. The subjective responses were evaluated on a 10 point scale. Results: The results showed that vibrotactile sensory perception in male amputees were higher than that in female amputees. In male amputees, the response at lateral area of forearm was the most sensitive than medial area; but, female amputees showed similar sensitive areas. Subjects did not experience any discomfort during vibrotactile stimuli. Conclusion: Vibrotactile response in the amputees was dependent on gender as well as area stimulated by vibration. Application: The results might contribute to develop the vibrotactile feedback system for the amputees.

This study tested the effectiveness of low-level laser therapy (LLLT) in preventing and/or treating osteoporotic trabecular bone. Mice were ovariectomized (OVX) to induce osteoporotic bone loss. The tibiae of eight OVX mice were treated for 5 days each week for 2 weeks by LLLT (660 nm, 3 J) using a minimally invasive laser needle system (MILNS) which is designed to minimize loss of laser energy before reaching bone (LASER group). Another eight mice received a sham treatment (SHAM group). Structural parameters of trabecular bone were measured with in vivo micro-computed tomography images before and after laser treatment. After LLLT for 2 weeks, the percentage reduction (%R) was significantly lower in BV/TV (bone volume fraction) and Tb.N (trabecular number, p0.05 and p0.05) and significant higher in Tb.Sp (trabecular separation) and SMI (structure model index, p0.05 and p0.05) than in the SHAM group. The %R in BV/TV at sites directly treated by LLLT was significantly lower in the LASER group than the SHAM group (p0.05, p0.05). These results indicated that LLLT using MILNS may be effective for preventing and/or treating trabecular bone loss and the effect may be site-dependent in the same bone.

This study was aimed to evaluate the effects of low-level laser therapy (LLLT) in the treatment of trabecular bone loss induced by skeletal unloading. Twelve mice have taken denervation operation. At 2 weeks after denervation, LLLT (wavelength, 660 nm; energy density, 3 J/cm2) was applied to the right tibiae of six mice (LASER) for 5 days/week over 2 weeks by using a minimally invasive laser needle system (MILNS) which consists of a 100 μm optical fiber in a fine needle (diameter, 130 μm). Structural parameters and histograms of bone mineralization density distribution (BMDD) were obtained before LLLT and at 2 weeks after LLLT. In addition, osteocyte, osteoblast, and osteoclast populations were counted. Two weeks after LLLT, bone volume fraction, trabeculae number, and trabeculae thickness were significantly increased and trabecular separations, trabecular bone pattern factor, and structure model index were significantly decreased in LASER than SHAM (p

It is widely known that sciatic nerve injury (SNI) can negatively affect the biomechanical characteristicsof the musculoskeletal system. However, there were no studies that evaluated and compared denervated side withanother side limb at the same time. In this study, sixteen male 12-week-old mice were allocated into two groups:HEMI (Right Sciatic nerve denervated) and CON (Control). Both limbs were scanned using micro-CT at 0 week and4 weeks. There were significant differences in relative variation (RV) of BMD and all structural parameters comparedCON and HEMI in right tibia (p < 0.05). Tb.Th and Tb.Sp distributions were differed CON with HEMI in right tibia.In left tibia, there were significant differences in RV of BMD (p < 0.05) and Tb.Sp distribution. These result meansthat SNI can induce bone loss in the both side tibiae. However, there was a different profile of bone loss betweenleft and right tibiae.Key words: Hemiplegia, Sciatic nerve injury, Trabecular bone, Bone loss

Many studies have reported that housework done using household appliances may affect biomechanical characteristics of the musculoskeletal system. The purpose of this study was to investigate the effects of housework done using a pulsator washing machine on joints and muscles. We calculated joint torques and muscle strengths on the basis of an experimental/virtual three-dimensional motion analysis for six healthy females using the pulsator washing machine at different heights (H) and depths (D) of the inside drum (H (mm){\times}D (mm), Trial1: , Trial2: , Trial3: , Trial4: , Trial5: ). The joint torques and muscle strengths tended to be considerably different during torso flexion in the sagittal plane for all the trials. The maximum joint torques for the thoracic vertebra, left ankle, and right shoulder measured in Trial4 were significantly higher than those measured in the other trials (p

This study was designed to investigate the effect of a combined stimulus which was composed of chi- ropractic massage and thermotherapy on the relief of mental and physical stress. Fifteen healthy male subjects were treated with three type of stimuli; control (without any stimulus), a single stimulus (only chiropractic) and a combined stimulus. To evaluate the effects of stimuli, visual analogue scale (VAS), trunk extension, electromyogram (EMG) on erector spinae muscle and electrocardiogram (ECG) were measured and analyzed before and after stimuli. In the control group, there were no significant changes in EMG root mean square (RMS) value and low Frequency / high Frequency (LF/HF) ratio (p > 0.05, p > 0.05). However, both stimulus groups showed significant increases in trunk extension and EMG RMS values (p < 0.05, p < 0.05), but significant decreases in LF/HF ratios (p < 0.05). Partic- ularly the decrement rate in LF/HF ratio was significantly higher in the combined stimulus group than that in the single stimulus group (p < 0.05). Also, a significantly lower VAS was recorded after combined stimulus. Our findings indicate that the combined stimulus might not only improve flexibility and strength of muscle, but also active para- sympathetic nerve activity. The combined stimulus may thus contribute to relieve the stress and to enhance the mus- cle function.

We have examined the effect of circadian disturbances induced by night shifts (NSs) on the phenotypes of the tibiae and abdominal adipose tissues (ADTs) in a mouse model by using in vivo micro-computed tomography (micro-CT). We found that the volumes of total and visceral ADTs in the night-shifted group of mice were significantly larger (69 and 92%, respectively) than those in the control. The mean polar moment of inertia, cross-sectional thickness, and bone mineral density of the cortical bone in the night-shifted group of mice were less (13, 5, and 3%, respectively) than those in the control. Moreover, the volume and the thickness of growth plates (GPs) of the tibiae in the night-shifted mice were significantly smaller (22 and 20%, respectively) than those in the control. Taken together, our results indicate that disturbances in the mouse circadian rhythms induced by NSs affect the morphological characteristics of cortical bone, the volume and the thickness of GPs, and the volume of ADTs.

Excessive bone resorption by osteoclasts relative to bone formation by osteoblasts results in the development of osteoporosis. Anti-osteoporotic agents that are able both to inhibit bone resorption and to stimulate bone formation are not available. We now show that water-soluble nacreous factors prepared from the pearl oyster Pteria martensii prevent osteoporotic bone loss associated with estrogen deficiency in mice mainly through osteoclast inactivation. Nacreous factors stimulated osteoblast biomineralization in vitro in association with activation of signaling by c-Jun NH(2)-terminal kinase (JNK) and Fos-related antigen-1 (Fra-1). They also suppressed both osteoclast formation by blocking up-regulation of nuclear factor of activated T cells cytoplasmic 1 (NFATc1) as well as bone pit formation mediated by mature osteoclasts, likely by disrupting the actin ring of these cells. Our findings thus show that the components of a natural material have beneficial effects on bone remodeling that are mediated through regulation of both osteoblast and osteoclast function. They may thus provide a basis for the development of biomimetic bone material as well as anti-osteoporotic agents.

The aim of this study was to determine whether sciatic nerve injury (SNI) can cause trabecular bone loss in not only the tibia, but also the lumbar vertebrae, and to investigate the correlation between baseline bone quantity (BV/TV, bone volume fraction) and the magnitude and rate of bone loss. Sixteen male C57BL/6 mice were used. Sciatic neurectomy (SNx) was carried out on both hind limbs of eight mice. The tibiae (T) and fourth lumbar vertebrae (L4) were scanned by in-vivo micro-computed tomography (micro-CT) before and at 2 weeks and 4 weeks after SNx. At 2 weeks and 4 weeks, BV/TVs in T and L4 were significantly lower in the SNx group than the non-SNx group (p < 0.05). There were significant negative correlations between BV/TV at 0 weeks and the relative variations in L4 at 2 weeks or in T at 4 weeks (p < 0.05). These results indicate that SNI can cause significant bone loss in the lumbar vertebrae and tibiae. The magnitude and rate of bone loss following SNI is affected by baseline bone quantity.

The pharmacological therapies and whole body vibration as non-pharmacological therapies were known to have adverse side effects. Therefore, partial stimulation was suggested and its effects were evaluated. This study aimed to evaluate the site-specific effects of partial stimulator for treatment of osteoporosis induced by estrogen deficiency. Sixteen virginal Sprague-Dawley rats (12 weeks old) were divided into 2 groups(no stimulation, stimulation groups). All rats were ovariectomised to induce osteoporosis. After 3 weeks of operation, the right tibiae in rats of stimulation group (frequency: 10Hz, cycle: 1500, strain on bone surface: 2000µe) were stimulated perpendicularly at right tibia by using partial stimulator for 6 weeks (3days/week). The right tibiae in rats were scanned, before stimulation (0 week) and at 6 weeks after stimulation by using invivo micro computed tomography. For investigation of changes in morphological characteristics, structural parameters were measured and calculated. At 6 weeks the morphological characteristics (relative value) in stimulation group were significantly enhanced than those in no stimulation group (p

RASSF2 belongs to the Ras-association domain family (RASSF) of proteins, which may be involved in the Hippo signalling pathway. However, the role of RASSF2 in vivo is unknown. Here, we show that Rassf2 knockout mice manifest a multisystemic phenotype including haematopoietic anomalies and defects in bone remodelling. Bone marrow (BM) transplantation showed that Rassf2−/− BM cells had a normal haematopoietic reconstitution activity, indicating no intrinsic haematopoietic defects. Notably, in vitro differentiation studies revealed that ablation of Rassf2 suppressed osteoblastogenesis but promoted osteoclastogenesis. Co-culture experiments showed that an intrinsic defect in osteoblast differentiation from Rassf2−/− osteoblast precursors likely leads to both haematopoiesis and osteoclast defects in Rassf2−/− mice. Moreover, Rassf2 deficiency resulted in hyperactivation of nuclear factor (NF)-κB during both osteoclast and osteoblast differentiation. RASSF2 associated with IκB kinase (IKK) α and β forms, and suppressed IKK activity. Introduction of either RASSF2 or a dominant-negative form of IKK into Rassf2−/− osteoclast or osteoblast precursors inhibited NF-κB hyperactivation and normalized osteoclast and osteoblast differentiation. These observations indicate that RASSF2 regulates osteoblast and osteoclast differentiation by inhibiting NF-κB signalling.

Systemic transplantation of adipose-derived stem cells (ASCs) is emerging as a novel therapeutic option for functional recovery of diverse damaged tissues. This study investigated the effects of systemic transplantation of human ASCs (hASCs) on bone repair. We found that hASCs secrete various bone cell-activating factors, including hepatocyte growth factor and extracellular matrix proteins. Systemic transplantation of hASCs into ovariectomized mice induced an increased number of both osteoblasts and osteoclasts in bone tissue and thereby prevented bone loss. We also observed that conditioned medium from hASCs is capable of stimulating proliferation and differentiation of osteoblasts via Smad/extracellular signal-regulated kinase (ERK)/JNK (c-jun NH(2) -terminal kinase) activation as well as survival and differentiation of osteoclasts via ERK/JNK/p38 activation in vitro. Overall, our findings suggest that paracrine factors secreted from hASCs improve bone repair and that hASCs can be a valuable tool for use in osteoporosis therapy.

This study aimed to predict bone fracture risk during skeletal unloading through a subject-specific finite element (FE) analysis considering heterogeneous tissue modulus. Twelve male and 14 female Institute of Cancer Research (ICR) mice (6 weeks old) were allocated into skeletal unloading and normal groups (each gender in both groups). The right hind tibia of each mouse in the skeletal unloading groups was subjected to sciatic neurectomy (denervation) and was scanned before and at 2 week after denervation using µCT. Bone volume (BV) and the distribution of Young's moduli (E) were measured from µCT images. The apparent modulus (Eapp) was calculated using the subject-specific (FE) analysis considering the heterogeneous tissue modulus derived by Hounsfield unit. At 2 weeks after denervation, the Eapp was significantly decreased in both genders (p < 0.05), and the distributions of E differed between the skeletal unloading and normal groups. However, the BV in females was significantly decreased (p < 0.05), while that in male was unchanged (p &gt 0.05). These results indicated that skeletal unloading reduced bone strength, leading to increased bone fracture risk.

Osteoporosis is a disease characterized by low bone mass, increased bone fragility, and a greater risk for bone fracture. Currently, pharmacological intervention can generally aid in the prevention and treatment of osteoporosis, but these therapies are often accompanied by undesirable side effects. Therefore, alternative therapies that minimize side effects are necessary. Biophysical stimuli, especially low-intensity ultrasound stimulation (LIUS), may be potential alternatives to drug-based therapies for osteoporosis. Hence, we sought to address whether LIUS therapy can effectively prevent or treat osteoporotic bone loss induced by estrogen deficiency. LIUS (1.5 MHz frequency, 1.0 kHz pulse repetition on frequency, 30 mW/cm(2) intensity, 200 µs pulse length) was applied to right tibiae of eight 14-week-old ovariectomized virgin ICR female mice for 20 min per day, 5 days per week, over a 6-week period. Changes in 3D structural bone characteristics were detected using in vivo micro-computed tomography. Left tibiae served as controls. Structural characteristics including bone volume/tissue volume, trabecular number, trabecular bone pattern factor, and mean polar moment inertia were significantly enhanced 6 weeks after LIUS compared to the control, nonstimulated group (p < 0.05). In particular, the bone volume/tissue volume in the region exposed directly to LIUS was significantly higher in the treated group (p < 0.05). These findings indicate that new bone formation may be activated or that bone structure may be maintained by LIUS, and that LIUS may be effective for preventing estrogen deficiency-induced bone loss.

Background: Conflicting data exist on the outcome of placing Bio-Oss® (Geitslich Pharm AG, Wolhausen, Switzerland) into extraction sockets. It is therefore relevant to study whether the incorporation of Bio-Oss into extraction sockets would influence bone healing outcome at the extraction sites. Purpose: The aim of this study was to assess peri-implant bone changes when implants were placed in fresh extraction sockets and the remaining defects were filled with Bio-Oss particles in a canine mandible model. Materials and Methods: Six mongrel dogs were used in the study. In one jaw quadrant of each animal, the fourth mandibular premolars were extracted with an elevation of the mucoperiosteal flap; implants were then placed in the fresh extraction sockets and the remaining defects were filled with Bio-Oss particles. After 4 months of healing, micro-computed tomography at the implant sites was performed. Osseointegration was calculated as the percent of implant surface in contact with bone. Additionally, bone height was measured in the peri-implant bone. Results: Average osseointegration was 28.5% (ranged between 14.8 and 34.2%). The mean crestal bone loss was 4.7 ± 2.1 mm on the buccal aspect, 0.4 ± 0.5 mm on the mesial aspect, 0.4 ± 0.3 mm on the distal aspect, and 0.3 ± 0.4 mm on the lingual aspect. Conclusion: The findings from this study demonstrated that the placement of implants and Bio-Oss® particles into fresh extraction sockets resulted in significant buccal bone loss with low osseointegration.

Osseointegration has been used as an index for prediction of long-term success of implant. Osseointegration has been routinely evaluated by measuring bone contact ratio on histology based on two-dimensional (2D) sections or images. However, these both methodologies have been less informative analysis of results and have several disadvantages. The aim of this study is to introduce new methodology for evaluation of a degree of osseointegration between bone and implant based on micro computed tomography (μ-CT) images. Specimen was scanned at a voxel resolution of 35 μ by μ-CT. Three-dimensional (3D) models of bone and implant were reconstructed respectively. Bone contact area (BCA) and bone contact area ratio (BCAR) were measured and calculated. Here, osseointegrated BCA between bone and implant surfaces was determined by computing areas of all bone regions existed within 35μ distance from implant surface. Osseointegration of flapless implant surgery was evaluated by new methodology, compared with that of flap implant surgery. BCA and BCAR in flapless implant surgery was significantly bigger than that in flap implant surgery (p