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PubMed1984

Plasma hormones (arginine vasotocin, prolactin, aldosterone, and corticosterone) in relation to hydration state, NaCl intake, and egg laying in fowls.

This review surveys our latest research dealing with the involvement of arginine vasotocin (AVT), the avian antidiuretic hormone, and other hormones in the regulation of water and salt balance in fowl. We examined the effect of dehydration, salt loading, high- and low-salt diets, and oviposition on plasma hormone levels and analyzed them in light of our knowledge of avian osmoregulatory responses to changes in water and salt balance. Gradual dehydration and hyperosmotic loading in domestic fowl revealed consistent differences in the AVT response between groups adapted to low- and high-NaCl diets. In birds on a low-NaCl diet the sensitivity of the AVT release was significantly higher than in birds on a high-NaCl diet. These results support the concept that the link between osmotic and volume regulation is established via varying sensitivity of the AVT release. We determined the half-life of the AVT in fowls (6.3 min), a value similar to that of ADH in mammals. We found that during oviposition, plasma AVT increases by a factor of four over the normal level, a magnitude consistent with the maximal responses revealed in osmotic stimulations. We have shown that as long as drinking water is available, heat exposure has no effect on the plasma osmotic constituents and the regulatory hormones. However, combined dehydration and heat exposure resulted in pronounced osmoregulatory responses integrated with the thermoregulatory responses to maintain water and salt balance without jeopardizing the birds' ability to cope with the thermoregulatory demands.(ABSTRACT TRUNCATED AT 250 WORDS)

Aldosterone↗

PubMed2004

The effect of short-duration sub-maximal cycling on balance in single-limb stance in patients with anterior cruciate ligament injury: a cross-sectional study.

BACKGROUND: It has previously been shown that an anterior cruciate ligament (ACL) injury may lead to impaired postural control, and that the ability to maintain postural control is decreased by fatigue in healthy subjects. To our knowledge, no studies have reported the effect of fatigue on postural control in subjects with ACL injury. This study was aimed at examining the effect of fatigue on balance in single-limb stance in subjects with ACL injury, and to compare the effects, and the ability to maintain balance, with that of a control group of uninjured subjects. METHODS: Thirty-six patients with unilateral, non-operated, non-acute ACL injury, and 24 uninjured subjects were examined with stabilometry before (pre-exercise) and immediately after (post-exercise) short-duration, sub-maximal cycling. In addition, the post-exercise measurements were compared, to evaluate the instantaneous ability to maintain balance and any possible recovery. The amplitude and average speed of center of pressure movements were registered in the frontal and sagittal planes. The paired t-test was used for the intra-group comparisons, and the independent t-test for the inter-group comparisons, with Bonferroni correction for multiple comparisons. RESULTS: No differences were found in the effects of exercise between the patients and the controls. Analysis of the post-exercise measurements revealed greater effects or a tendency towards greater effects on the injured leg than in the control group. The average speed was lower among the patients than in the control group. CONCLUSIONS: The results of the present study showed no differences in the effects of exercise between the patients and the controls. However, the patients seemed to react differently regarding ability to maintain balance in single-limb stance directly after exercise than the control group. The lower average speed among the patients may be an expression of different neuromuscular adaptive strategies than in uninjured subjects.

Adolescent↗

PubMed2003

Support for patients loosing sight.

This overview on support of patients loosing sight is based on a literature survey regarding reading disabilities and orientation and on results of experience trials performed at the University Eye Clinic Tübingen. In reading disorders, the main goal of rehabilitation is to regain or maintain the ability to read newspaper print. The fundament of rehabilitation is the use of optical and electronical devices and the application of specially designed training programs. The ability of a person with low vision to achieve successful orientation and mobility rehabilitation depends on residual vision, posture and balance, body image, auditory and tactile abilities, intelligence and personality. Rehabilitation efforts focus on the enhancement of residual vision applying magnifying contrast-enhancing and photomultiplying devices. The main pillar of orientation and mobility rehabilitation is a training especially designed for the patient's needs. Rehabilitation efforts must be tailored to the type of vision loss and to specific functional implications--the success rate is high. An optimal fitting of the required spectrum of low vision aids should be provided to the patient and importantly, professional teaching and training is recommended. Activities of daily living, orientation and mobility, and psychological concerns must be addressed. Close cooperation with other branches of rehabilitation is essential.

Humans↗

PubMed2000

Puzzling associations between childhood infections and the later occurrence of asthma and atopy.

The current unfavourable trends in asthma and atopy prevalences have raised great concern and have challenged investigators to accelerate search for new risk factors for atopic diseases. The lack or scarcity of intense, systemic infections in early life has been postulated to increase susceptibility of becoming sensitized to otherwise harmless allergens in later life. This hygiene hypothesis is considered one of the most plausible explanations for the current trends in atopic diseases to date. There are data to suggest that measles, hepatitis A, and Mycobacterium tuberculosis infection in early life may prevent the subsequent development of atopic diseases. The hypothesis is based on the concept that certain viral and bacterial infections, which induce a strongly polarized T helper (Th)-1 type response and a long-lasting memory immunity, are in early life able to reverse or prevent the biased Th1/Th2 balance in individuals prone to atopy and asthma. Evidence for the ability of mycobacterial infections to alter the Th1/Th2 balance has also been obtained from murine models. In humans, the critical time period during which immunomodulation with long-lasting effects is considered most successful is within the first two years of life. Possibly also nonpathogenic residents of the intestinal mucosa are involved in the proper maturation of the immune system. The use of antibiotics has been shown to be positively associated with the development of asthma and atopy. The mechanisms underlying these associations remain largely unknown.

Anti-Bacterial Agents↗

PubMedDate not supplied

Admission balance and outcomes of patients admitted for acute inpatient rehabilitation.

The objective of the study contained herein was to evaluate the clinical use of the Berg Balance Scale in a heterogeneous acute inpatient rehabilitation population and to assess the relationship between balance scores at admission and rehabilitation outcomes, including functional gain and length of stay. This was a prospective study of 45 patients with diagnoses including stroke (n = 15), traumatic brain injury (n = 19), and other impairments (n = 11) who were admitted for acute inpatient rehabilitation. Functional ability was evaluated with the Functional Independence Measure (FIM) instrument, and balance was measured using the 14-item Berg Balance Scale. These measures were assessed both at admission to and discharge from inpatient rehabilitation. Correlation and multiple regression analyses were used to determine the relationship between balance and functional ability scores at admission and rehabilitation outcomes at discharge, including length of stay, functional gain, and efficiency. Analyses of variance comparing impairment groups indicated that patients with traumatic brain injury were younger than the stroke and other groups, but there were no group differences on FIM or balance scores at admission or discharge. There were no significant group differences for any of the outcome measures. When the impairment groups were collapsed into a single heterogeneous group, multiple regression analyses demonstrated that the sitting unsupported item score at admission accounted for 27% of the variation in length of stay, once demographic influences were controlled. The FIM efficiency score was predicted best by the total Berg Balance Scale score, with 22% of the variance accounted for. In contrast, balance scores did not provide predictive information about the FIM gain score beyond that already provided by the FIM-Total score at admission, which accounted for 10% of the variance once demographics were controlled. Balance scores collected at admission to inpatient rehabilitation, in whole and in part, were shown to account for moderate amounts of variation in length of stay and the FIM efficiency score. For several of the rehabilitation outcomes, balance scores at admission accounted for more variation than scores on the FIM instrument. These findings suggest that routine assessment of balance at admission to inpatient rehabilitation may enhance the ability to predict rehabilitation outcomes beyond that provided by assessment of functional status alone.

Adult↗

PubMed1997

Balance and vertical impact in sports: role of shoe sole materials.

OBJECTIVE: Athletic shoes and mats are support surface interfaces composed of relatively soft compressible materials designed to protect against injuries occurring in sports through force of vertical impact. Impact remains high with their use because humans land harder with them. We hypothesize that this hard-landing strategy is an attempt by the user to improve stability, by compressing the material to a less destabilizing thinner-stiff variety. We tested this hypothesis by comparing impact and balance on materials consisting of ethyl-vinyl acetate (EVA) foams of varying stiffness, identical to that found in soles of athletic footwear. DESIGN: Randomized-order, crossover trial, controlled comparison, blinded. SETTING: Volunteers were selected from the general community. PARTICIPANTS: A random sample of 12 healthy men from the general population (mean age 30 years, SD +/- 6). Additional selection criteria were absence of disabilities influencing ability to walk, run, and balance, and no history of frequent falls. METHODS: Impact testing and stability measures were performed on the same test day. Ground reaction forces were measured for ten barefoot footfalls. The protocol required stepping forward from perch to surface 4.5 cm below. Stability testing was performed with one-legged standing consisting of placing left foot on top of right for 30 sec, barefoot, eyes open, and gaze straight, with arms to side. Subjects confronted four surface conditions presented in random order: a bare rigid platform, and the platform covered with one of three 2.5-cm-thick materials. RESULTS: Steady state vertical impact was a negative function of interface stiffness, with the softest interface producing the greatest vertical impact, and the stiffest interface the least vertical impact. Vertical impact and stability measures were also negatively related, with the strongest correlation obtained with the softest interface (r = -.87, p < .001). No relation between these variables was obtained for the rigid surface. CONCLUSION: Balance and vertical impact are closely related. This supports the hypothesis that landing hard on soft surfaces is an attempt to transform the interface into a form associated with improved stability. According to these findings, currently available sports shoes and mats are too soft and thick, and should be redesigned to protect the persons using them.

Adult↗

PubMed2005

Characteristics of ammonium removal by heterotrophic nitrification-aerobic denitrification by Alcaligenes faecalis No. 4.

Alcaligenes faecalis no. 4 has heterotrophic nitrification and aerobic denitrification abilities. By taking the nitrogen balance under different culture conditions, 40-50% of removed NH4+-N was denitrified and about one-half of removed NH4+-N was converted to intracellular nitrogen. The maximum ammonium removal rate of no. 4 (28.9 mg-N/l/h) and its denitrification rate at high-strength NH4+-N of about 1200 ppm in aerated batch experiments at a C/N ratio of 10 were 5-40 times higher than those of other bacteria with the same ability. Only a few percent of the removed ammonium was converted to nitrite, and the main denitrification process was speculated to be via hydroxylamine which was produced by ammonium oxidation.

Aerobiosis↗

PubMed1995

Role of brown adipose tissue thermogenesis in control of thermoregulatory feeding in rats: a new hypothesis that links thermostatic and glucostatic hypotheses for control of food intake.

The hypothesis proposed in this review provides a novel view of both the control of feeding and the function of brown adipose tissue (BAT) thermogenesis. It takes into account the episodic nature of feeding in rats allowed free access to food and the necessity for episodic events in the controlling systems which govern initiation and termination of feeding. A feeding episode is proposed to occur during an episode of increased sympathetic nervous system activity that stimulates BAT thermogenesis and increases body temperature. Two different aspects of stimulated BAT metabolism, namely increased uptake of glucose and increased heat production, evoke initiation and termination of feeding, respectively. Initiation is mediated by a transient dip in blood glucose concentration caused by stimulated glucose utilization in BAT. Feeding continues while both BAT and core temperature continue to rise. Termination is induced by the high level of core temperature brought about by the episode of stimulated BAT thermogenesis. The time between initiation and termination determines the size of the meal and depends on the balance between BAT thermogenesis and heat loss, and thus on ambient temperature. The underlying cause of the episodic stimulation of sympathetic nervous system activity is a decline in core temperature to a level recognized by the hypothalamus as needing a burst of increased heat production. Thus, BAT thermogenesis is important in control of meal size, relating it to thermoregulatory needs. When this function is lost, as in many obese animal models of obesity, the animal loses its ability to remain in energy balance by precisely adjusting its intake in relation to environmental temperature and meal size increases. The hypothesis also predicts that an increase in endogenous heat production that is not due to BAT thermogenesis will prevent the matching of intake to increased expenditure via thermoregulatory feeding. This is seen, for example, in the shivering rat during the early stage of acclimation to cold. Feeding is viewed as the outcome of a thermoregulatory event. Rats do not eat to warm up; they start to eat after they have started to warm up and stop eating once they have warmed up. The phenomenon is termed thermoregulatory feeding, to distinguish it from feeding initiated by other stimuli.

Adipose Tissue, Brown↗

PubMed1985

Assessment of fluid balance in isolated sheep lungs.

In this study we demonstrate the validity and utility of an isolated lung preparation developed for the study of pulmonary fluid balance. Lungs of 2- to 3-mo-old sheep were perfused in situ with autologous blood treated with indomethacin (20 micrograms/ml). Lung lymph flow (QL), uncontaminated by systemic lymph, was measured from either the efferent duct of the caudomediastinal lymph node or the thoracic duct in the superior mediastinum. Lung weight change (delta W) was measured as the opposite of the change in weight of the extracorporeal blood reservoir. A unique feature of this experimental model is the ability to assess lung fluid balance from simultaneous measurements of delta W and QL. In addition, hemodynamic and blood gas variables can be tightly controlled. Our results show that changes in QL and the lymph-to-plasma oncotic pressure ratio caused by an increase in microvascular pressure were comparable with those seen previously in intact sheep. When microvascular pressure was returned to control levels, QL fell despite a sustained increase in the amount of extravascular lung water, suggesting compartmentalization of the filtrate and/or effects of intravascular volume on lymph-driving pressure or resistance. Lymph flow was directly proportional to respiratory frequency over the range of 0-30 min-1 when the change in frequency was maintained for periods as long as 30 min. This preparation should prove useful in the study of lung fluid balance, particularly when it is desired to use interventions which are precluded or difficult in intact animals.

Animals↗

PubMed2005

Role of the basal ganglia in balance control.

In this review paper, we summarize the important contributions of the basal ganglia to the regulation of postural control. After a brief overview of basal ganglia circuitries, the emphasis is on clinical observations in patients with focal lesions in parts of the basal ganglia, as the impairments seen here can serve to highlight the normal functions of the basal ganglia nuclei in postural control. Two particularly relevant functions are discussed in detail: first, the contribution of the basal ganglia to flexibility and to gaining control of balance-correcting responses, including the ability to lend priority to the elements of a postural task; and second, processing afferent information by the basal ganglia, which is increasingly recognized as being highly relevant for postural control.

Adaptation, Physiological↗

PubMed1981

The digestive capacity of the caecum-colon and the value of the nitrogen absorbed from the hind gut for protein synthesis in pigs.

1. The aim of the investigation was to study the effects of lysine, methionine, crude protein, a complete balanced diet, maize starch and potato starch infused continuously into the caecum on the digestibility of the nutrients, urinary nitrogen excretion and N balance in the presence of a normal or a depressed (modified) microflora. 2. The effects of the the infused nutrients on digestibility differed when diets supplemented with antibiotics were compared with unsupplemented diets. 3. Infused lysine improved the digestibility of crude protein (0.004/g lysine), crude fibre (0.01/g lysine), gross energy (0.003/g lysine) and lysine (0.03/g lysine) when the diets were not supplemented with antibiotics. 4. Infused lysine, methionine and crude protein seemed to be of very little value for protein synthesis in the pigs, as the effects on N balance, although positive, were very small. 5. Despite the fact that a part of the infused lysine passed through the caecum-colon and into the faeces intact, the effect of N balance was negligible, indicating that the ability to absorb amino acids through the gut wall in the caecum-colon was very poor. 6. Crude protein, a complete balanced diet, maize starch and potato starch infused into the caecum were digested almost as well as if they had been given orally, thus demonstrating the large digestive capacity of the caecum-colon.

Animals↗

PubMed1986

Aging and posture control: changes in sensory organization and muscular coordination.

The following study examined two aspects of balance control in the older adult: the coordination of the timing and the amplitude of muscle responses to postural perturbations, and the ability of the participant to reorganize sensory inputs and subsequently modify postural responses as a consequence of changing environmental conditions. Coordination of muscle activity in postural responses of twelve elderly (sixty-one to seventy-eight years) participants were compared to those of young (nineteen to thirty-eight years) adults using a movable platform and recording the electromyographic activity of muscles of the legs. The following changes were noted in the timing and amplitude of muscle activity within a postural response synergy: increases in the absolute latency of distal muscle responses were observed in all older adults; in five of the twelve older adults temporal reversals of proximal and distal muscle response onset were observed; and there was a breakdown in the correlation of the amplitude of responses within a synergy. The ability of the older adult to balance under conditions of reduced or conflicting sensory information was also impaired. When confronted with functionally inappropriate visual and/or somatosensory inputs, half of the older group lost balance. In most instances, however, the older participants were able to maintain stability during subsequent responses to conflicting stimuli.

Adaptation, Physiological↗

PubMed1988

Response preparation and posture control. Neuromuscular changes in the older adult.

Experiments comparing the characteristics of neuromuscular responses underlying balance control in young and old adults have shown a number of differences between the two populations. Postural muscle response latencies of the ankle musculature activated by external threats to balance are slightly, but significantly, longer in the latter population. In addition, some aging subjects show a temporal reversal of proximal and distal muscle response onset in some trials. There is also a breakdown of the correlation of the amplitude of the muscle responses within a synergy in some of the older subjects tested. Older adults also exhibited cocontraction of agonist and antagonist muscles within a response synergy to a greater extent than young adults. This stiffening of the joints by antagonist cocontraction could be a compensation for the lack of the ability to fine-tune the postural responses to the same degree as the young adults. Analysis of sensory integration abilities showed an impairment in balance control under conditions of reduced or conflicting sensory information. When they were given inappropriate visual and somatosensory inputs, half of the older adults lost balance on the first trial. In most instances, however, the older adults were able to maintain balance during a second trial consisting of the same sensory stimuli. When visual cues were reduced by restricting the visual field to either central or peripheral visual cues, we found no difference in postural muscle response latencies. However, the aging adult group showed more losses of balance than the younger group with peripheral vision removed or with eyes closed. In addition, there was a strong correlation between the subjects that showed stronger deficits on an initial neurological exam and the number of times that balance was lost. Studies on changes in the linkage between postural and voluntary muscle interactions during voluntary arm movements in older adults indicate an increase in the latency of feed-forward activation of postural muscles. However, voluntary muscle response onset latencies show greater increases in the old compared to the young. This suggests that deterioration of the speed of activation of the postural control system is not the only factor that limits the speed of voluntary movement onset. Measurements have not yet been made on the amplitude regulation of feed-forward responses of postural muscles during a voluntary task. It may be that the regulation of the speed of activation of the two systems is less important than the fine tuning of the correlation of appropriate response amplitudes between the two systems.(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗

PubMed1998

Relative hand skill predicts academic ability: global deficits at the point of hemispheric indecision.

Population variation in handedness (a correlate of cerebral dominance for language) is in part genetic and, it has been suggested, its persistence represents a balanced polymorphism with respect to cognitive ability. This hypothesis was tested in a sample of 12,770 individuals in a UK national cohort (the National Child Development Study) by assessing relative hand skill (in a square checking task) as a predictor of verbal, non-verbal, and mathematical ability and reading comprehension at the age of 11 years. Whereas some modest decrements were present in extreme right handers the most substantial deficits in ability were seen close to the point of equal hand skill ('hemispheric indecision'). For verbal ability females performed better than males, but the relationship to relative hand skill was closely similar for the two sexes; for reading comprehension males close to the point of equal hand skill showed greater impairments than females. Analysed by writing hand the relationship of ability to hand skill appeared symmetrical about the point of 'hemispheric indecision'. The variation associated with degrees of dominance may reflect the operation of continuing selection on the gene (postulated to be X-Y linked) by which language evolved and speciation occurred.

Achievement↗

PubMed2003

Oral-antigen delivery via a water-in-oil emulsion system modulates the balance of the Th1/Th2 type response in oral tolerance.

PURPOSE: To evaluate the ability of a water-in-oil (W/O) emulsion containing ovalbumin (OVA), a model antigen, to induce oral tolerance and to elucidate the mechanism for the induction of oral tolerance by the emulsion system. METHODS: A W/O emulsion containing OVA was prepared and evaluated its ability to induce oral tolerance in mice. Also, the Th1/Th2 balance in the mice tolerized was investigated in terms of the ratios of anti-OVA IgG2a titer to anti-OVA IgG1 titer (IgG2a/IgG1 ratios) and cytokine profiles. RESULTS: Anti-OVA total IgG antibody titer of mice administered OVA in saline was approximately 3.5-fold higher than that of the mice administered OVA in W/O emulsion at a dose of 0.1 mg/mouse/day. Similar total IgG responses were observed between the above two at a dose of 1 mg/mouse/day. The IgG2a/IgG1 ratios decreased as the dose of OVA in W/O emulsion, but not in saline, increased at doses of 0, 0.1, and 1 mg/mouse/day. Interferon-gamma secretion of PLN cells from the mice administered OVA in W/O emulsion decreased, whereas their interleukin-4 secretion remained high. Although interferon-gamma secretion for the mice administered OVA in saline decreased, interleukin-4 secretion did not change. CONCLUSIONS: The present study suggests that oral delivery of OVA via the W/O emulsion system may more efficiently enhance the induction of Th2-dominated imbalance than that of OVA in saline.

Administration, Oral↗

PubMed2005

Developmental regulation of cognitive abilities: modified composition of a molecular switch turns on associative learning.

N-methyl-D-aspartate receptors (NMDARs) act as molecular coincidence detectors and allow for association or dissociation between pre- and postsynaptic neurons. NMDA receptors are central to remodeling of synaptic connections during postnatal development and associative learning abilities in adults. The ability to remodel neural networks is altered during postnatal development, possibly due to a change in the composition of NMDARs. That is, as forebrain systems (and cerebellum) develop, synaptic NR2B-containing NMDARs (NR2B-NMDARs) are replaced by NR2A-containing NMDARs (NR2A-NMDARs) and NR2B-NMDARs move to extrasynaptic sites. During the initial phase of the switch, synapses contain both NR2A- and NR2B-NMDARs and both long-term potentiation and long-term depression are enhanced. As NMDAR subunit expression decreases and NR2A-NMDARs come to predominate in the synapse, channel function and synaptic plasticity are reduced, and remodeling ability dissipates. The end result is a balance of plasticity and stability that is optimal for information processing and storage. Associative learning abilities involving different sensory modalities emerge sequentially, in accordance with synaptic maturation in related cortical and underlying brain structures. Thus, developmental alterations in NMDAR composition that occur at different ages in various brain structures may explain the protracted nature of the maturation of various associative learning abilities.

Animals↗

PubMed2003

Exercise and injury prevention in older people.

This review aims to provide the reader with up to date evidence in relation to the role of exercise in the reduction of risk factors and the prevention of falls and injuries. Falls and injury may lead to a spiral of inactivity and decline that take older people close to or below the critical "thresholds" of performance necessary for everyday activities. Yet, low strength and power, poor balance, poor gait and functional ability, and fear of falling are all risk factors for falls modifiable with tailored exercise. Although the evidence on types, amounts and specificity of exercise to prevent falls is not complete, recommendations have been published that have been effective, either as an exercise stand-alone intervention or with exercise as part of a multifactorial intervention. It is clear that the target population must be at risk or already fallers, they must be "not too fit" and "not too frail". Supervised home-based exercise programs may be effective in those aged over 80 because they fall more frequently, injure more easily, and recover more slowly. In younger, community-dwelling, fallers multifactorial group interventions including targeting of balance, strength, power, gait, endurance, flexibility, co-ordination and reaction may be more effective. There are, however, research questions that still need answering - whether there are certain types of exercise harmful in certain subgroups of older people, what is the ideal intensity, frequency and duration of exercise for different subgroups of older people (primary and secondary prevention) and the relative value of the different components of fitness to prevention of falls and injuries. This review highlights the necessity of tailored, specific balance and strength exercise in the multidisciplinary prevention of falls and injuries.

Accidental Falls↗

PubMed2003

Spinal anesthesia: functional balance is impaired after clinical recovery.

BACKGROUND: The ability of patients to walk without assistance after spinal anesthesia is a determining factor in the time to discharge following ambulatory surgery. The authors compared clinical markers of gross motor recovery with objective data of functional balance after spinal anesthesia. METHODS: Twenty-two male patients with American Society of Anesthesiology physical status I or II who were scheduled for perineal surgery were studied during recovery from spinal anesthesia to compare the predictive accuracy of clinical markers of ambulatory readiness (e.g., full knee flexion and extension) with that of an objective method of measurement focused on functional balance. Lumbar puncture was performed at the L2-L3 or L3-L4 interspace using a 25-gauge Whitacre needle, with patients in the sitting position. A 3-ml mixture of 5 mg bupivacaine (heavy) and 10 microg fentanyl was injected. Block regression and restoration of motor function were assessed and recorded. Functional balance was measured using a computerized force platform method. RESULTS: The majority of patients maintained motor function and proprioception sensation at the onset of surgical anesthesia, as indicated by performance on clinical tests of function: 96% were able to perform the straight leg increase; 82, 77, and 91%, respectively, were able to perform full knee flexion and extension, perform heel-to-shin maneuvers, and identify joint position in the supine position. Postoperatively, clinical return of motor function occurred much earlier than recovery of functional balance. At 60 min after onset of spinal anesthesia, 22 patients (100%) had recovered sensory and gross motor function, but only 36% could stand, and 8% could walk without assistance (P < 0.01). At 150-180 min after onset, 96-100% of patients achieved the levels of functional balance that permitted adequate ambulation. CONCLUSIONS: The results suggest that the recovery time to unassisted ambulation is longer than has been assumed, and that the standard clinical markers of gross motor function are poor predictors of functional balance following ambulatory surgery.

Adolescent↗