[Current evidence based interventions for preventing fall and fall-related hip fracture of the older people].

For older people, the consequences of falling include injury, fear of falling, decreased activity, functional deterioration, reduced quality of life, and death. According to reliable systematic reviews and guidelines, exercise programs including balance and strength training, multifactorial interventions, and home safety assessment and modification interventions are effective at reducing the rates of falls and risks of falling among community-dwelling elderly people. Taking vitamin D supplements might be effective for reducing falls in older people who exhibit lower vitamin D levels in the blood. Hip protectors apparently reduce the risk of hip fractures in frail older residents of care facilities. Taking vitamin D with calcium supplements might reduce the risk of hip fractures.

Differences in walking and running parameters in elementary school students with and without backpacks.

BACKGROUND: Backpack syndrome (BS) is a term used to describe symptoms such as shoulder and back pain that are believed to be caused by carrying a backpack. Few studies have investigated the changes in walking and running parameters with and without backpacks. OBJECTIVE: The present study aimed to investigate the differences in walking and running parameters with and without backpacks in primary school children with and without BS. METHODS: This cross-sectional study included 51 children (average age 9.3 years, 6- 12 years). Two questions were asked beforehand: whether the respondents had shoulder or back pain when going to school and present; those who answered that they had pain in both cases were defined as the BS group, while the others were the control group. Walking and running at comfortable speeds and walking and running with a 6 kg backpack on their backs were measured. RESULTS: During walking, there were main effects for speed, cadence, and strike angle with and without the backpack, but no interactions were identified for any of the parameters. In running, however, there were main effects for speed, stride length, strike angle, and lift-off angle, and an interaction effect was observed for speed and stride length. CONCLUSIONS: During walking, carrying a 6 kg backpack increased cadence and walking speed. During running, carrying a backpack caused a decrease in stride length and running speed in the BS group, whereas there was no change in the control group, suggesting that the control and BS groups may respond differently.

The effect of a shoe lift on tensor fasciae latae length during standing with an artificial functional leg length discrepancy: An ultrasonic shear wave elastography study.

BACKGROUND: Shortening of tensor fasciae latae is one factor that causes a functional leg length discrepancy. A shoe lift has been used to correct the compensatory posture resulting from the discrepancy. Despite the potential therapeutic benefit of a shoe lift, the mechanism by which it exerts its effect is unclear. OBJECTIVE: To investigate the effect of a shoe lift on tensor fasciae latae length during standing with an artificial functional leg length discrepancy using ultrasonic shear wave elastography. METHODS: Twenty-two healthy individuals performed static standing under three conditions: drop of the pelvis and flexion of the leg resulting from fixing in the hip abduction position using a hip orthosis (functional leg length discrepancy condition); drop of the pelvis by the orthosis, but no flexion of the leg due to a shoe lift (shoe lift condition); and normal bilateral standing condition. The shear elastic modulus of tensor fasciae latae was calculated using ultrasonic shear wave elastography. RESULTS: The shear elastic modulus was significantly lower in the functional leg length discrepancy condition than in the shoe lift and normal conditions (p= 0.038). CONCLUSIONS: Using a shoe lift for the functional leg length discrepancy can result in a functional hip position that elongates tensor fasciae latae.

How does wearing slippers affect the movement strategy while crossing over an obstacle?

BACKGROUND: Wearing slippers may increase the risk of tripping while crossing obstacles, regardless of age. This is because slippers are more likely to leave the feet and come into contact with obstacles. However, how wearing slippers affects the movement strategy while crossing over an obstacle has not been clarified. RESEARCH QUESTION: How does wearing slippers affect the movement strategy while crossing over an obstacle? METHODS: Thirty healthy young adults crossed over an obstacle using a comfortable speed under two conditions: barefoot and wearing slippers. The moment when the leading or trailing limb was crossing the obstacle was defined as obstacle lead (OL) or obstacle trail (OT), respectively. The margin of stability (MoS) as a measure of stability was measured at OL and OT. Toe clearance and lower limb joint angles of the leading limb were measured at OL, and those of the trailing limb were measured at OT. RESULTS: Wearing slippers increased toe clearance and flexed the hip and knee joints, regardless of the crossing event (OL, OT). However, the ankle joint angle did not change between footwear conditions at OL and was significantly dorsiflexed in the slippered condition at OT. In addition, the MoS did not change between footwear conditions at OL and increased significantly in the slippered condition at OT. SIGNIFICANCE: The increase of the MoS at OT when wearing slippers is probably a conservative strategy to reduce the risk of falling forward when a trip occurs. More attention to avoiding tripping likely caused the ankle to dorsiflex and increased toe clearance. This conservative strategy and increased attention are most likely due to the slippers coming off easily. Since these strategies are probably safety measures to prevent tripping, slippers may not be appropriate footwear in terms of tripping risk.

Effects of restriction of forefoot rocker functions by immobilisation of metatarsophalangeal joints on kinematics and kinetics during walking.

OBJECTIVE: This study was conducted to investigate the effects of restriction of forefoot rocker (FFR) functions by immobilisation of unilateral metatarsophalangeal joints (MPJs) on kinematic and kinetic factors during walking. METHODS: Eighteen healthy young adults participated in this study. To immobilise the MPJs of the right leg, an aluminium sole plate (AS) was fixed on the sole of the foot. Kinematic and kinetic data were collected while each subject walked at a comfortable speed with the AS and without. RESULTS: In the AS condition, the walking speed and contralateral step length were significantly decreased, and an asymmetrical centre of mass (COM) movement was observed. The range of plantarflexion motion and positive work by the ankle joint were decreased markedly during the late stance of the AS limb. In contrast, maximum hip and knee flexion angles in the swing phase of the AS limb and positive work by the bilateral hip joints over the gait cycle were increased. CONCLUSIONS: The results suggested that MPJ immobilisation may result in marked motion limitation of ankle plantarflexion and inhibition of push-off by the ankle joint despite no restrictions on the ankle joint. These changes may interfere with gait speed and a smooth and symmetrical COM shift during walking.

Does the balance strategy during walking in elderly persons show an association with fall risk assessment?

The primary objective of this study was to clarify whether balance evaluation during walking in elderly people was related to fall risk assessment; the second objective was to clarify the difference in balance strategy between young and elderly people based on the balance evaluation through a gait cycle. Thirty healthy young adults and 25 healthy elderly adults participated. All participants performed walking at their preferred speed and at a fast speed. Based on the margin of stability (MoS), balance during a gait cycle was divided into medial/lateral and anterior/posterior direction (ML/AP-MoS). Positive/negative integral values of ML-MoS were defined as ML-MoSPOS/ML-MoSNEG, and the average of AP-MoS over the gait cycle was defined as AP-MoSmean. The fast/preferred ratio of AP-MoSmean/ML-MoSPOS (AP-MoSmean (Fast/Preferred)/ML-MoSPOS (Fast/Preferred)) and the fast-preferred difference of ML-MoSNEG (ML-MoSNEG (Fast-Preferred)) were compared between groups. ML/AP-MoS at the preferred/fast gait was also compared between 12 gait events and groups. The Japanese version of the Mini-Balance Evaluation Systems Test (J-Mini-BESTest), the Japanese version of the Activities-specific Balance Confidence Scale (J-ABC scale), and the number of falls in the past year were obtained from all subjects. ML-MoSPOS (Fast/Preferred), ML-MoSNEG (Fast-Preferred), and AP-MoSmean (Fast/Preferred) were significantly correlated with J-Mini-BESTest. Gait balance evaluation based on MoS may reflect an individual's balance function. In fast gait, ML-MoS at foot flat and toe off and AP-MoS at just before heel strike were highly likely to be gait events to identify elderly adults with balance disorders.

Investigation of balance strategy over gait cycle based on margin of stability.

This study was conducted to investigate the balance strategy of healthy young adults through a gait cycle using the margin of stability (MoS). Thirty healthy young adults participated in this study. Each performed walking five times at a preferred speed and at a fast speed. The MoS was calculated over a gait cycle by defining the base of support (BoS) changes during a gait cycle. The MoS was divided into medial/lateral and anterior/posterior components (ML MoS and AP MoS). The central values and the values at 12 gait events of the MoS were compared. Positive/negative integration of ML MoS (ML MoSPOS and ML MoSNEG, respectively) and the average ML/AP MoS over a cycle (ML/AP MoSmean) were significantly lower at a fast gait than at a preferred gait. ML/AP MoS were lower at a fast speed than at the preferred speed, except for the ML MoS immediately before left heel strike (pre left HS) and right and left heel strike (HS). ML/AP MoS were significantly lower immediately before heel strike (pre-HS) than in other gait events, regardless of walking speed. It was suggested that pre-HS is the most unstable moment in both ML/AP directions and a crucial moment in control of gait stability. The results presented above might be applicable as basic data regarding dynamic stability of healthy young adults through a gait cycle for comparisons with elderly people and patients with orthopedic disorders or neurological disorders.

Evaluation of the activities of the medial and lateral heads of quadratus plantae in flexion movements of the lateral four toes using ultrasound real-time tissue elastography.

Quadratus plantae (QP), one of the plantar intrinsic foot muscles, assist plantarflexion of the lesser toes. QP has medial and lateral muscle heads with different anatomical structures. The two heads of this muscle may have different roles in foot function. Ultrasound real-time tissue elastography (RTE) measurements have allowed quantitative assessment of deep-layer muscle elasticity. The purpose of this study was to determine the activity of the QP in flexion movements of the lateral four toes using RTE. Thirteen healthy subjects performed maximal voluntary contractions using a hand-held dynamometer with external belt fixation for each toe flexion movement. The elasticity of the muscles were measured using RTE during rest and flexion of each toe. The strain ratio of the muscle to that in an acoustic coupler was calculated as an index of muscle elasticity. Higher strain ratio values imply lower elasticity. The strain ratio of the medial head of QP for second toe flexion (0.10±0.11) was significantly stiffer than at rest (0.34±0.33). The strain ratios of the lateral head of QP for flexion of the second (0.32±0.19), third (0.41±0.37), fourth (0.33±0.26), and fifth (0.45±0.39) toes were significantly stiffer than at rest (1.02±0.68). These results suggest that the medial head of QP has a role in assisting second-toe flexion, and the lateral head has a role in assisting flexion of all four lateral toes.

Effects of vertical motion of the centre of mass on walking efficiency in the early stages after total hip arthroplasty.

PURPOSE: The purpose of this study was to identify factors related to walking efficiency in the early postoperative period of total hip arthroplasty (THA). METHODS: The subjects of this study were 18 women who had undergone unilateral THA 4 weeks before and 18 healthy women as control. Using a force plate and a 3-D motion analyser, we measured: 1) gait speed, stride length, cadence; 2) centre of mass displacement in the three directions; 3) asymmetry of the centre of mass movement in vertical direction; and 4) the total internal work per unit mass and distance walked (a negative index of walking efficiency). RESULTS: Compared with healthy persons, THA patients showed significantly greater total internal work per unit mass and distance walked. The vertical centre of mass motion of the THA patients demonstrated an asymmetrical pattern. In THA patients, the stepwise multiple regression analysis selected the displacement and the asymmetrical vertical motion of centre of mass as the sole significant variable affecting walking efficiency (R2 = 0.81). CONCLUSIONS: Our findings indicated that rehabilitation programs that control the vertical movement of the centre of mass during gait are important to improve walking ability in the early post-operative phase after THA.

Gait analysis of patients in early stages after total hip arthroplasty: effect of lateral trunk displacement on walking efficiency.

BACKGROUND: Control of the mediolateral displacement of the center of gravity (COG) is considered to be important for efficient walking. Few studies have been published on the relation between walking efficiency and the lateral displacement of the trunk, pelvis, or COG in patients soon after total hip arthroplasty (THA). The present study was undertaken to examine the effects of lateral displacement on walking efficiency after THA. METHODS: The subjects of this study were 15 women who had undergone unilateral THA 4 weeks before and 14 healthy women as controls. Using a force plate and a three-dimensional motion analyzer, we measured (1) gait speed, stride length, cadence; (2) lateral trunk displacement (LTD) and lateral pelvis displacement (LPD); (3) lateral displacement of the center of gravity; and (4) the total internal work done per unit mass and distance walked (a negative index of walking efficiency) (WE(-1)). RESULTS: Compared with healthy persons, THA patients showed significantly increased amplitude of LTD and greater WE(-1) (P < 0.01). The WE(-1) value of the THA group was 21.4% higher than that of the control group. The results suggest that the patients need more energy to progress their body forward in a gait cycle, indicating reduced walking efficiency. In THA patients, the stepwise multiple regression analysis selected LTD as the sole significant variable affecting WE(-1) (R(2) = 0.72, P < 0.01). CONCLUSIONS: These results suggest that trunk compensation strategy for hip abductor weakness in patients soon after THA can lead to increased energy expenditure.

Evaluation of hip fracture risk in relation to fall direction.

The purpose of this study is to evaluate hip fracture risk in relation to fall direction, and to elucidate factors that influence the impact force in falls on the hip. Eight healthy volunteers performed deliberate falls in three directions (lateral, posterolateral and posterior) on a force platform covered by a mattress of 13 cm thickness. Fall descent motions and impact postures were examined by a three-dimensional analyzer. The maximum ground force reaction, velocity of the greater trochanter at impact, and activity of quadriceps and gluteus medius were measured. In all trials of lateral and posterolateral falls, but not of posterior falls, the subjects hit their greater trochanter directly on the mattress. The impact forces were between 2,000 N and 4,000 N. Posterolateral falls showed significantly higher velocity at impact than did posterior falls. The height and the lower limb length exhibited positive correlations with the impact force in all directions of fall. In the lateral fall, there was a positive correlation between the activity of quadriceps and the impact force. In view of the impact point, force, and velocity, the posterolateral fall seemed to carry the highest risk of hip fracture.