A study was conducted to determine the effect of aging on motor ability and to establish a test battery for physical fitness in the elderly. The subjects were 150 men aged 18 to 83 years. The test items examined were selected, according to Fleishman's list of motor abilities; (1) trunk flexion, (2) grip and isometric knee extension strength, (3) postural sway with eyes open and closed, (4) step test, (5) walking test at preferred and maximum speeds, (6) simple visual reaction time, (7) peg-board test, (8) finger tapping test at maximum rate and in time to metronome sounds. Performances for the test items, except for preferred walking speed and coefficient of variation in finger tapping at 5 Hz, showed significant decreases with aging. The decrease in motor performance at age 80 years relative to the level at age 20 years was less than 30% for finger dexterity and reaction time, 40-60% for muscle strength, maximum walking speed and the step test, and over 70% for trunk flexion and postural sway with eyes closed. A test battery composed of trunk flexion, grip strength, knee extension, step test, walking as fast as possible, postural sway with eyes closed, and finger tapping, is therefore recommended for assessing the effect of aging on physical fitness.

A motor performance test was administered to elderly adults in Koganei City and Nangai Village of Japan as the baseline study of Tokyo Metropolitan Institute of Gerontology, Longitudinal Interdisciplinary Study on Aging (TMIG-LISA) . The participants in this study totaled 405 (183 males and 222 females) aged 65 to 84 from Koganei City, and 734 (295 males and 439 females) aged 65 and over from Nangai Village. The test consisted of measurement of grip strength, one-leg stand-ing, walking at preferred and maximum speeds, and finger-tapping. All motor performances examined were higher among males than females, and they all deteriorated with aging. A regional difference was found in terms of motion speed abilities: finger-tapping rate and walking speed were higher among urban residents than rural residents. Individual differences (coefficient of variation) in the motor ability increased with aging, and reached 106% (maximum tapping rate in female) to 290% (maximum walking speed in female) of those in the twenties. Significant correlations between motor abilities were detected indicating that the specificity of the motor ability found in the young may not account for older adults.

The effects of aging on adaptive force control of precision grip while manipulating a small object were compared between older (84.2±8.9 yrs, n=33) and young adults (19.1±0.24 yrs, n=18) from the following perspectives: (1) adaptation to an unfamiliar object with uncertain physical properties during 16 consecutive lifts ; (2) adaptation to an object with a non-slippery (sandpaper) surface during 12 consecutive lifts, followed by 12 consecutive lifts with a slippery (silk) surface ; and (3) adaptation to objects with different weights (0.49, 0.98, 1.96 and 2.94 N) during 24 lifts (6 consecutive lifts for each weight) .During each trial, grip and load forces were monitored. Safety margin force and slip force were evaluated from the data obtained.
The majority of older adults employed a considerably greater safety margin for an unfamiliar object in the initial trials than did young adults, while the minority of the older adults were able to adapt their safety margin force with a few trials, like the young adults. The older adults who overestimated the safety margin force, however, successfully adjusted their grip force to more optimal levels with repeated lifts, suggesting that the adaptive capability of grip force remained even at 90 years of age. The adaptation of older adults, however, was found to be slower (i. e., required more trials) than that of young adults. Upon encountering surface friction change, the safety margin forces in older adults were more strongly affected by the previous surface condition than those in the young adults. In addition, adaptation to a non-slippery surface seemed more difficult than that to a slippery surface with aging. Upon encountering weight change, older adults showed more difficulties in scaling their safety margin forces according to object weights.
Slower adaptation and difficulty in adaptation to the friction or weight change in older adults may reflect the agerelated decline of tactile sensitivity which impaired the signaling of frictional conditions and various discrete events in the hand. In addition, the lift repetition for force adaptation may possibly reflect the age-related deficit or slowing of central processing capacities related to grip force production.

STUDY DESIGN: A retrospective study. PURPOSE: To examine the effectiveness of using an electrodiagnostic technique as a new approach in the clinical diagnosis of extraforaminal stenosis at L5-S1. OVERVIEW OF LITERATURE: We introduced a new effective approach to the diagnosis of extraforaminal stenosis at the lumbosacral junction using the existing electrophysiological evaluation technique. METHODS: A consecutive series of 124 patients with fifth lumbar radiculopathy were enrolled, comprising a group of 74 patients with spinal canal stenosis and a second group of 50 patients with extraforaminal stenosis at L5-S1. The technique involved inserting a pair of needle electrodes into the foraminal exit zone of the fifth lumbar spinal nerves, which were used to provide electrical stimulation. The compound muscle action potentials from each of the tibialis anterior muscles were recorded. RESULTS: The distal motor latency (DML) of the potentials ranged from 11.2 to 24.6 milliseconds in patients with extraforaminal stenosis. In contrast, the DML in patients with spinal canal stenosis ranged from 10.0 to 17.2 milliseconds. After comparing the DML of each of the 2 groups and at the same time comparing the differences in DML between the affected and unaffected side of each patient, we concluded there were statistically significant differences (p<0.01) between the 2 groups. Using receiver operating characteristic curve analysis, the cutoff values were calculated to be 15.2 milliseconds and 1.1 milliseconds, respectively. CONCLUSIONS: This approach using a means of DML measurement enables us to identify and localize lesions, which offers an advantage in diagnosing extraforaminal stenosis at L5-S1.
Action Potentials ; Constriction, Pathologic* ; Diagnosis* ; Diagnostic Techniques and Procedures ; Electric Stimulation ; Electrodes ; Humans ; Muscles ; Needles ; Radiculopathy ; Retrospective Studies ; ROC Curve ; Spinal Canal ; Spinal Nerves ; Spinal Stenosis

STUDY DESIGN: Prospective cohort imaging study. PURPOSE: This study aimed to evaluate lumbar sagittal alignment and range of motion (ROM) using radiographs in a large asymptomatic cohort and identify sex-based differences and age-related changes in the subjects. OVERVIEW OF LITERATURE: Several researchers have tried to establish normal alignment and kinematic behavior of the lumbar spine, using plain radiographs. Few studies have employed a large and sex-and age-balanced cohort. METHODS: Total 627 healthy volunteers (at least 50 males and 50 females in each age decade, from the 3rd to the 8th decade) underwent whole spine radiography in the standing position; lumbar spine radiography was performed for all subjects in the recumbent position. Lumbar lordosis (LL, T12–S1) and ROM during flexion and extension were measured using a computer digitizer. RESULTS: The mean LL was 36.8°±13.2° in the recumbent position and 49.8°±11.2° in the standing position. The LL was greater in the standing position than in the recumbent position; further, LL was higher in females as compared to that in males. Local lordosis at each disk level increased incrementally with distal progression through the lumbar spine in both the positions. Local lordosis at L4–S1 was 29.8°±8.0° in the recumbent position and 34.2°±8.3° in the standing position and occupied 85.1% and 70.8% of the total LL, respectively. However, local lordosis in the standing position decreased with age at L2–3, L3–4, and L4–5 levels. Total lumbar ROM (T12–S1) decreased with age. The ROM in females was higher than that in males. CONCLUSIONS: We established the standard value and age-related changes in the lumbar alignment and ROM in each age decade in asymptomatic subjects. These data will be useful and provide the normal values for comparison in clinical practice to identify sex-based differences and age-related changes.
Animals ; Cohort Studies ; Female ; Healthy Volunteers ; Humans ; Lordosis ; Male ; Posture ; Prospective Studies ; Radiography ; Range of Motion, Articular ; Reference Values ; Spine

BACKGROUND: Studies on the adverse effects of Asian dust (AD) on respiratory function in children are scarce. The objective of this study was to examine the association between AD and respiratory function by measuring peak expiratory flow rates (PEFRs) in asthmatic children. METHODS: The study was carried out from March to May from 2014 through 2016. One hundred ten children with bronchial asthma were recruited from four hospitals in the Goto Islands and south Nagasaki area in Nagasaki prefecture. The parents were asked to record their children's PEFRs every morning/evening and clinical symptoms in an asthma diary. AD was assessed from light detection and ranging data, and a linear mixed-effects model was used to estimate the effects of AD on daily PEFR. Time-stratified case-crossover analyses were performed to examine the association between AD and asthma attacks defined by reduction levels in PEFR. RESULTS: AD was detected on 11 days in the Goto Islands, and on 23 days in the south Nagasaki area. After adjusting for age, sex, temperature, and daily oxidants, we found a consistent association between AD and a 1.1% to 1.7% decrease in PEFR in the mornings and a 0.7% to 1.3% decrease in the evenings at a lag of 0 to 5 days. AD was not associated with the number of asthma attacks, respiratory symptoms, or other symptoms at any lag days examined. CONCLUSIONS Exposure to AD was associated with reduced PEFR, although the effects were not large enough to induce clinically apparent symptoms, in clinically well-controlled asthmatic children.