The relationship between perceived exertion and physiologic indicators of stress during graded arm exercise in persons with spinal cord injuries

OBJECTIVE: To examine the relationship between psychologic cues of somatic stress and physiologic responses to exercise in persons with paraplegia and tetraplegia. DESIGN: Repeated measures with 2 comparison groups. SETTING: Academic medical center. PARTICIPANTS: Forty-two subjects between 18 and 69 years of age with motor-complete spinal cord injury (SCI) resulting in paraplegia or tetraplegia (American Spinal Injury Association grades A and B). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Subjects underwent peak graded arm ergometry during which heart rate, oxygen consumption (VO2), minute ventilation (VE), and ratings of perceived exertion (RPE) (Borg Categorical 6-20 Scale) were measured at successive work rate increments from baseline to fatigue. RESULTS: There were inconsistent associations among the outcomes. For subjects with tetraplegia, RPE related positively to heart rate at the initial work rate, but there were no other significant correlations. For subjects with paraplegia, RPE did not correlate significantly with heart rate, VO2, or VE. VO2 and Ve related positively at the first and last work rates. In general, heart rate, VO2, and Ve increased as the exercise intensity increased, and were more pronounced in subjects with paraplegia. While RPE values increased with increasing work rates for each group, we found no differences between groups. CONCLUSIONS: Our findings contradict the well-accepted relationships between RPE and both heart rate and VO2 during exercise by people without disabilities, and challenge the use of RPE as a valid psychophysiologic index of perceived exertion in persons with SCI.     

Comparison of core neuromuscular control and lower extremity postural stability in athletes with and without shoulder injuries

BackgroundThe kinetic chain theory is widely used as a rationale for the inclusion of core stability training in athletes. Core stability (muscle capacity and neuromuscular control) impairments may result in less than optimal performance and abnormal force dissipation to the shoulder complex that could lead to shoulder injuries. However, a paucity of literature exists to support this relationship, and no previous studies have investigated the relationship between isolated core neuromuscular control and shoulder injuries. Additionally, lower extremity postural stability has been associated with athletic function and may also be associated with shoulder injuries. The purpose of this study was to compare biomechanical measures of isolated core neuromuscular control and lower extremity postural stability between athletes with and without non-traumatic shoulder injuries.MethodsEighty athletes (55 males, age: 21.2 ± 3.3 years, 40 with a current shoulder injury) completed biomechanical measures of isolated core neuromuscular control and lower extremity postural stability. Athletes were matched by age, gender, body mass index, and sport type. MANOVAs were used to assess differences between measures of core neuromuscular control and lower extremity postural stability between groups.FindingsThere were no statistically significant differences between athletes with and without shoulder injuries for the static core neuromuscular control measures, F(4,75) = 0.45, P = 0.78, η² = 0.02; dynamic core neuromuscular control measures, F(4,75) = 0.81, P = 0.52, η² = 0.04; or lower extremity postural stability measures, F(8,61) = 0.85, P = 0.56, η² = 0.10.InterpretationAlthough core stability is widely incorporated in rehabilitation of athletes with shoulder injuries, athletes with current non-traumatic shoulder injuries may not present with impairments in core neuromuscular control or lower extremity postural stability.     

Rehabilitation of the patient with a lower extremity amputation.

Preservation of life is an incomplete and inadequate objective for the lower extremity amputee. A comprehensive rehabilitation program must be designed to meet his individual needs. This is the responsibility of the professional community that purports to treat disease and maintain the health of the population. The multidisciplinary team functions in a coordinated effort to identify and resolve the amputee's problems, and to establish realistic goals during each phase of his rehabilitation program. The rehabilitation process begins when the prospective LE amputee is identified and continues until he has achieved optimal independence; that is, he has learned to cope with his disability within the boundaries of his normal environment.     

Comparison of respiratory muscles activity and exercise capacity in patients with idiopathic scoliosis and healthy individuals

Abstract

Purpose: Idiopathic scoliosis causes respiratory muscles weakness and reduced exercise capacity. However, the mechanism of these symptoms is still unknown. The main objective of this study was to determine the intensity of respiratory muscle activity and exercise capacity in patients with idiopathic scoliosis in comparison with healthy people. Subjects: In this study, 20 female patients with adult idiopathic scoliosis (10 mild and 10 moderate) as well as 10 healthy matched individuals with characteristics of the patients were selected. Methods: The subjects were fatigued through a maximal incremental cycle ergometry protocol. Meanwhile, the electromyography values of the external intercostal muscles and diaphragm were recorded bilaterally, and fatigue duration was determined. Results: The root mean square of concave external intercostal muscles and concave diaphragm in patients with idiopathic scoliosis was significantly reduced during the fatiguing exercise protocol compared with healthy individuals. The median frequencies of the two sides differed significantly and were lower in patients with moderate scoliosis than healthy subjects. Fatigue duration (minutes) also was lower in patients with moderate scoliosis than healthy subjects. Conclusions: Scoliosis causes respiratory muscle weakness and reduced fatigue duration in response to mild physical activity compared with healthy subjects and these dysfunctions appear to be related to the severity of scoliosis curvature (moderate > mild).     

Decreased peak arteriovenous oxygen difference during treadmill exercise testing in individuals infected with the human immunodeficiency virus

OBJECTIVE: To determine if arteriovenous oxygen difference was lower in asymptomatic individuals with human immunodeficiency virus (HIV) infection than in sedentary but otherwise healthy controls. DESIGN: Quasi-experimental cross-sectional. SETTING: Clinical exercise laboratory. PARTICIPANTS: Fifteen subjects (10 men, 5 women) with HIV and 15 healthy gender- and activity level-matched controls (total N=30). INTERVENTION: Participants performed an incremental maximal exercise treadmill test to exhaustion. Electrocardiogram, metabolic, and noninvasive cardiac output measurements were evaluated at rest and throughout the tests. Data were analyzed by using analysis of covariance. MAIN OUTCOME MEASURES: Peak oxygen consumption (Vo(2)), cardiac output, stroke volume, and arteriovenous oxygen difference. The arteriovenous oxygen difference was determined indirectly using the Fick equation. RESULTS: Peak VO(2) was significantly lower (P<.0005) in participants with HIV (24.6+/-1.2mL.kg(-1).min(-1)) compared with controls (32.0+/-1.2mL.kg(-1).min(-1)). There were no significant intergroup differences in cardiac output or stroke volume at peak exercise. Peak arteriovenous oxygen difference was significantly lower (P<.04) in those infected with HIV (10.8+/-0.5 volume %) than in controls (12.4+/-0.5 volume %). CONCLUSION: The observed deficit in aerobic capacity in the participants with HIV appeared to be the result of a peripheral tissue oxygen extraction or utilization limitation. In addition to deconditioning, potential mechanisms for this significant attenuation may include HIV infection and inflammation, highly active antiretroviral therapy medication regimens, or a combination of these factors.     

Modes of balanced regional anesthesia in patients with lower extremity injuries

The basic hemodynamic (systolic blood pressure (BP), diastolic BP, heart rate, stroke volume, cardiac output, RPP) and respiratory parameters (respiratory rate, tidal volume, respiratory minute volume) during operations on the lower extremities under epidural anesthesia (n=24; Group 1) versus lumbar plexus block by the 3-in-1 technique (n= 23; Group 2) were studied in 47 traumatological patients. With balanced epidural anesthesia, there was a short-term decrease in hemodynamic parameters and a worse external respiratory function; in 5 patients requiring its performance WL, balanced block of peripheral nerves of the lumbar plexus was, on the contrary, marked by a greater hemodynamic and respiratory stability.     

Use of a ramp surface for lower extremity exercise with burn-injured patients

The use of a ramp surface in our Burn Center has demonstrated benefits in improving gait, standing postures, and lower extremity muscle length. This technique has been effective with a wide age range of patients and is most useful as part of an overall treatment program including prestretching of lower extremities.     

Concurrent musculoskeletal pain in a patient with symptomatic lower extremity arterial insufficiency

The etiology of back and lower extremity pain can, at times, be difficult to differentiate. This is especially true in cases where two pain-producing conditions coexist. Such difficulties have been reported in cases of coexisting vascular and neurogenic claudication. We report the case of a 66-year-old woman with concurrent musculoskeletal pain and hip claudication. Her arterial insufficiency was initially masked by her diffuse pain complaints and only became apparent to us after successful treatment of her soft tissue problems. We caution physicians to be aware of coexisting musculoskeletal pain that may mask significant underlying pathology.     

Reliability of lower extremity strength measures in persons with chronic stroke

OBJECTIVE: To determine the reliability of isokinetic concentric strength measures of both the hemiparetic and noninvolved limbs for flexion and extension motions of the hip, knee, and ankle joints in individuals who have had a stroke. DESIGN: Test-retest, repeated-measures intraobserver reliability design. SETTING: Tertiary rehabilitation center. PARTICIPANTS: Twenty community-dwelling individuals who have had a stroke, with motor deficits ranging from 3 to 6 on the Chedoke-McMaster Stroke Assessment; volunteer sample. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Peak torque and average torque (ie, mean over the range of motion tested) from an ensemble-averaged (3 trials) torque-angle curve during isokinetic concentric extension and flexion movements of the ankle, knee, and hip. RESULTS: Although peak and average torque were significantly less for the hemiparetic limb compared with the noninvolved limb, the intraclass correlation coefficients (ICCs) between the 2 test sessions were high (.95-.99 for peak torque,.88-.98 for average torque) for both limbs for all 3 joints. However, there was a learning effect, as observed by the slightly greater values attained from the second test session. CONCLUSIONS: Peak and average isokinetic torque can be used to assess reliably lower extremity strength in persons with chronic stroke. Practice sessions may be required before the actual test to reduce the effect of learning.     

Comparison of isocapnic hyperventilation and treadmill exercise in children with exercise-induced asthma

The degree of post-exercise airway obstruction (Exercise-Induced Asthma (EIA] in 14 children was compared to the degree of airway obstruction following isocapnic hyperventilation. EIA was provoked by 6 min of treadmill running. Isocapnic hyperventilation was performed sitting during 6 min. The total ventilation (Vtot) during the two provocations was identical. The temperature of the inspired air was also identical during the two provocations, and the relative humidity was 40% during treadmill-running and 15% during hyperventilation. The decrease in peak expiratory flow after treadmill-running was 29%. After hyperventilation a fall on 19% was seen. These figures are statistically different. It is concluded that although there is a significant difference in airway obstruction after the two provocations the ventilation is greater importance for EIA than is the work load.     

Wearing a safety harness during treadmill walking influences lower extremity kinematics mainly through changes in ankle regularity and local stability

Background  

Wearing a harness during treadmill walking ensures the subject's safety and is common practice in biomedical engineering research. However, the extent to which such practice influences gait is unknown. This study investigated harness-related changes in gait patterns, as evaluated from lower extremity kinematics during treadmill walking.     

Significance of ST depression during exercise treadmill stress and adenosine infusion myocardial perfusion imaging

Background: ST segment depression on the electrocardiogram during the exercise treadmill test (ETT) is used as a predictor of coronary artery disease (CAD), although it is recognised that both false-positive and false-negative results limit the value of this procedure. Although adenosine does not produce an inotropic or chronotropic effect upon the myocardium it may cause ST depression during infusion. Methods: The 12-lead ECG recordings obtained during 825 adenosine stress and 425 ETT procedures, performed as part of a 2-day Tc-MIBI protocol, were retained for examination and comparison with the appearances at subsequent myocardial perfusion imaging (MPI). Results: ST depression was associated with 44 (4.9%) of the adenosine stress and 44 (10.4%) of the ETT procedures. Both 1 and 2 mm ST depression during adenosine stress were significant predictors of reversible ischaemia (p < 0.01; p < 0.01). However, even though 2 mm ST depression on ETT was significant as a predictor of reversible ischaemia (p < 0.01), 1 mm ST depression on ETT was not (p = 0.4). There were more female cases with false positive ECG changes in both the adenosine stress (63.6%) group and the ETT (66.7%) group. There was no significant correlation between the territory of the ischaemic changes seen on the ECG with the location of defects developing on MPI in both the adenosine stress and ETT groups.Conclusions: ST depression of 1 mm occurring with adenosine stress, unlike with the ETT, is a significant predictor of ischaemia.     

Evaluation of quantitative measures of upper extremity speed and coordination in healthy persons and in three patient populations

Upper extremity tracking tests have been used extensively in clinical studies in patients with neurologic disorders. We evaluated several new measures of upper extremity performance derived from step-response and phase-plane analysis techniques; both techniques are founded in automatic control theory. Using a computer-based tracking test, a visual step function stimulus was applied in 15 healthy subjects and 45 patients from multiple sclerosis, myasthenia gravis, and Parkinson disease populations. The upper extremity response of the subject was analyzed to find the reliability and discriminating power measures that quantify speed, coordination, and steadiness of the upper extremity response during the tracking task. Results show that reliability of the measures, although variable across the populations tested, is generally high (greater than 0.7). The speed and coordination measures derived from phase-plane analysis are more discriminating than the measures of step-response analysis for the populations tested. Some of the measures may be useful for monitoring patient performance, the other measures can be potentially helpful in diagnosis of the disorders.     

Alterations in lower extremity movement and muscle activation patterns in individuals with knee osteoarthritis

OBJECTIVE: The purpose of this study was to investigate lower extremity movement and muscle activation patterns in individuals with knee osteoarthritis and healthy age- and gender-matched control subjects. DESIGN: This study utilized a non-randomized case-control design to compare 24 subjects with unilateral symptomatic knee osteoarthritis to 24 age- and gender-matched control subjects without knee osteoarthritis. BACKGROUND: It is hypothesized that knee osteoarthritis is associated with altered lower extremity movement and muscle activation patterns. METHODS: A gait analysis was performed to determine the lower extremity movement and muscle activation patterns when walking on a level surface at 1.12 to 1.34 m/s and while descending a 20 cm step. Paired t-tests were used to compare the average of five trials between the groups. RESULTS: Subjects with knee osteoarthritis demonstrated less excursion of the knee in the sagittal plane from heelstrike to peak flexion before midstance (i.e. during loading). Subjects with knee osteoarthritis also demonstrated reduced peak vertical ground reaction forces relative to body weight. The muscle activity patterns were also different between the groups. The vastus lateralis, medial hamstrings, tibialis anterior and medial gastrocnemius were on approximately 1.5 times longer than the same muscles in the control subjects. Additionally, significant increases in muscle co-activation were also observed in individuals with knee osteoarthritis during walking. Similar findings were observed when the subject descended a 20 cm step.     

烧伤科护士的职业危害分析与防护对策

为减少或消除烧伤科护士职业危害,通过对烧伤科护士最常面临的生物、化学、物理、运动功能、心理社会等方面的职业危害进行分类,分析原因并制订防护措施,包括提高烧伤科护士的自身防护意识和职业技能,优化护理工作流程,实施科学管理,降低护士体能消耗和心理压力,以减少烧伤科护士职业危害。     

Comparison of pulse oximetry measures in a healthy population

In this study finger and ear oximetry readings of 89 healthy persons were compared. The findings do not support the common nursing practice of using a finger sensor to obtain a pulse oximetry reading from an individual's ear if the finger is not usable.