Biomedical subjects

B J de Lateur

Publications and source records attributed to B J de Lateur.

At least 19 recordsLinked to original sources

PubMed1999

Continuous passive motion for osteoarthritis of the hip: a pilot study.

OBJECTIVE: To evaluate whether extended use of continuous passive motion (CPM) may allay the pain of walking, diminish disease effect, and increase the usual walking speed in patients with osteoarthritis (OA) of the hip. METHODS: This pilot study comprised 21 patients with Kellgren-Lawrence grade 2-4 OA of the hip who used CPM for periods of 1.2 to 7.6 h daily throughout a 12 week trial. RESULTS: Significant improvements were found in the patients' assessment of pain on visual analog scale, Sickness Impact Profile, self-selected walking speed, and the number of subjects who decreased their medication usage. None of these improvements was related to the radiographic grade of the patients' OA or the daily duration of CPM. CONCLUSION: Although regular exercise is now routinely recommended to patients with OA, there has been relatively little study of specific exercise programs. As such investigations are undertaken, we believe CPM should be included among the options that are studied.

Adult↗

PubMed1998

Mass and mass distribution of below-knee prostheses: effect on gait efficacy and self-selected walking speed.

OBJECTIVE: To study mass and mass distribution effect on function of below-knee prostheses. DESIGN: Design modifications were done to produce proximal center of mass location versus distal center of mass location variations, and prosthesis weight was modified from 42% to 70% of normal limb weight. Work across joints of affected and unaffected extremities was compared to assess the ability of the prosthesis to substitute for function loss. SETTING: University biomechanics laboratory. PARTICIPANTS: Fifteen volunteers with below-knee amputations, residual limb length greater than 8.3 cm, but excluding Syme amputations. INTERVENTIONS: Patients walked with all configurations at self-selected walking speeds and 120 m/min. MAIN OUTCOME MEASURES: Self-selected walking speed and metabolic efficiency. Work across the joints of affected and unaffected sides was compared. RESULTS: Proximal center of mass location produced a more efficient gait. Weight change from 42% to 70% of normal had no significant effect. Mechanical studies show that the prosthesis is a relatively poor substitute for the normal limb; most work is done by the nonamputated side. Particularly, the prosthesis failed to produce effective forward impulses on the body, resulting from push-off and deceleration of the swing leg. CONCLUSIONS: For a proximal center of mass, lightweight distal components (e.g., feet) should be used; it is questionable whether further expenditure to develop ultralightweight prostheses would be cost effective for level walking.

Adolescent↗

PubMed1997

The effect of strength and endurance training on gait, balance, fall risk, and health services use in community-living older adults.

BACKGROUND: The study tested the effect of strength and endurance training on gait, balance, physical health status, fall risk, and health services use in older adults. METHODS: The study was a single-blinded, randomized controlled trial with intention-to-treat analysis. Adults (n = 105) age 68-85 with at least mild deficits in strength and balance were selected from a random sample of enrollees in a health maintenance organization. The intervention was supervised exercise (1-h sessions, three per week, for 24-26 weeks), followed by self-supervised exercise. Exercise groups included strength training using weight machines (n = 25), endurance training using bicycles (n = 25), and strength and endurance training (n = 25). Study outcomes included gait tests, balance tests, physical health status measures, self-reported falls (up to 25 months of follow-up), and inpatient and outpatient use and costs. RESULTS: There were no effects of exercise on gait, balance, or physical health status. Exercise had a protective effect on risk of falling (relative hazard = .53, 95% CI = .30-.91). Between 7 and 18 months after randomization, control subjects had more outpatient clinic visits (p < .06) and were more likely to sustain hospital costs over $5000 (p < .05). CONCLUSIONS: Exercise may have beneficial effects on fall rates and health care use in some subgroups of older adults. In community-living adults with mainly mild impairments in gait, balance, and physical health status, short-term exercise may not have a restorative effect on these impairments.

Accidental Falls↗

PubMed1996

Evidence for a non-linear relationship between leg strength and gait speed.

Although the relationship between strength and physical performance in older adults is probably non-linear, few empirical studies have demonstrated that this is so. In a population-based sample of adults aged 60-96 years (n = 409), leg strength was measured in four muscle groups (knee extensor, knee flexor, ankle plantar flexor, ankle dorsiflexor) of both legs using an isokinetic dynamometer. A leg strength score was calculated as the sum of the four strength measurements in the right leg. Usual gait speed was measured over a 15.2 metre course. With a linear model, leg strength explained 17% of the variance in gait speed. Non-linear models (quadratic and inverse) explained significantly more variance (22%). The nature of the non-linear relationship was that, in stronger subjects, there was no association between strength and gait speed, while in weaker subjects, there was an association. Body weight and age also explained significant amounts of variance in gait speed, while sex and height did not. The results supported the hypothesis of a non-linear relationship between leg strength and gait speed that is similar for older men and women. This finding represents a mechanism for how small changes in physiological capacity may have substantial effects on performance in frail adults, while large changes in capacity have little or no effect in healthy adults.

Adult↗

PubMed1996

Factors associated with changes in gait speed in older adults.

BACKGROUND: The study addressed whether changes in gait speed in community-dwelling older adults were associated with changes in fitness (strength and aerobic capacity), physical health status, and/or depressive symptoms. METHODS: The study sample comprised 152 community-dwelling adults aged 68-85 who had participated in an exercise study. Study measures at baseline and 6-month follow-up included gait speed, a leg strength score, maximal aerobic capacity (VO2max), CES-Depression scale, and physical health status (SIP Physical Dimension). RESULTS: In cross-sectional regression analyses, leg strength, VO2max, weight, and the strength by VO2max interaction term were significant independent predictors of gait speed (R2 = 26%). Based upon the observed 7% increase in VO2max and 8% increase in strength in the exercise groups, the regression model predicted only a 2% (1.5 m/min) increase in gait speed, which did not differ significantly from the observed increase of 0% (.32 m/min). The strongest correlate of change in gait speed was change in CES-D scores (partial R = -.37). Change in physical health status also correlated with change in gait speed (partial R = -.28), while change in fitness did not. CONCLUSIONS: The results suggest, in the range of fitness of the study sample, that changes in gait speed are related to changes in depressive symptoms and physical health status, but not to modest changes in fitness. A model assuming nonlinear relationships may be appropriate for understanding how strength and aerobic capacity affect gait speed.

Aged↗

PubMed1996

The relationship of joint symptoms with exercise performance in older adults.

OBJECTIVES: The objective of this study is to determine if exercise increases joint symptoms in older adults with a history of arthritis or produces symptoms in older adults without such history. In addition, we examine whether joint symptoms explain the large observed variation in strength gain in older adults undergoing vigorous strength training exercise, and report the incidence of musculoskeletal injuries upon initiation of an exercise program. DESIGN: A population-based, single blinded, randomized controlled trial with three exercise groups and one control group. SETTING: A large urban health maintenance organization. PARTICIPANTS: Older men and women (N = 105) aged 68 to 85, with leg strength below the 50th percentile for their age, sex, height, and weight and without neuromuscular disease or active cardiovascular disease. INTERVENTIONS: Supervised exercise in 1-hour sessions, three times each week, for 24 to 26 weeks. One exercise group did strength training (ST) using weight machines (n = 25); another group did endurance training (ET) using stationary cycles (n = 25); and the third group did combined strength training and endurance training (ST+ET) (n = 25). The control group (n = 30) received no intervention. MEASUREMENTS: Strength was measured at the ankle, knee, hip, and elbow using an isokinetic dynamometer. Joint symptoms were rated on a 6-point scale (0 = none, 5 = severe). Arthritis severity was based on self-reported use of arthritis medication. Health status was measured with subscales of the SF-36 and Sickness Impact Profile (SIP). RESULTS: Joint symptoms fluctuated over time in all exercise groups, but they did not improve or worsen significantly in any group. The physical dimension of the SIP and SF-36 subscale scores, including Bodily Pain Scores, did not change over time in any group. Subjects with arthritis and joint symptoms gained as much strength with strength training as did subjects without joint symptoms. Adjustment for age, gender, baseline strength, adherence, and exercise group did not affect this finding. The rate of minor musculoskeletal injuries was 2.2 injuries per 1000 exercise hours. CONCLUSIONS: Moderate intensity stationary cycle exercise and vigorous intensity strength training do not appear to produce or exacerbate joint symptoms in older adults. Joint symptoms did not explain the large variation in gains in strength in older adults participating in a standardized strength training exercise program. Musculoskeletal injuries occurred relatively infrequently, and no major injuries occurred. In evaluating joint pain that occurs in older adults in well regulated exercise programs, clinicians should consider other etiologies before attributing pain to exercise per se.

Aged↗

PubMed1994

Isokinetic testing of ankle strength in older adults: assessment of inter-rater reliability and stability of strength over six months.

The study purposes were (1) to estimate the inter-rater reliability of isokinetic strength tests at the ankle in older adults (test-retest interval of three to 7 days), and to determine whether more experienced examiners were more reliable; and (2) to estimate 6 month stability of strength tests. Inter-rater reliability was high for plantar flexion and dorsiflexion tests where average strength was more than about 10 Newton-meters (Nm) (Pearson R = 0.87-0.95). When average strength was less than 10Nm, reliability was less (R = 0.42-0.75). Experienced examiners (physical therapists) and less experienced examiners (research assistants) were equally reliable. Variability in strength over 6 months was no greater than variability over a few days. We conclude that isokinetic tests of ankle strength in older adults are highly reliable and stable when examiners are adequately trained and subjects maintain usual physical activity levels.

Aged↗

PubMed1993

The Seattle FICSIT/MoveIt study: the effect of exercise on gait and balance in older adults.

While exercise is generally recommended for older adults, the specific role of exercise in preventing falls and frail health is unclear. The Seattle FICSIT/MoveIt study is a population-based, randomized, controlled trial comparing the effects of three 6-month exercise interventions (endurance training, strength training, or combined endurance and strength training), and three 3-month endurance training interventions (stationary cycle, walking, or aerobic movement). Primary study outcomes are aerobic capacity, strength, gait, balance, and physical functional status. The study enrolls adults age 68-85 who have leg weakness and impaired gait. It differs from most previous community-based exercise studies in several respects: recruitment of subjects from a defined population; eligibility criteria based upon physiologic and functional status deficits; random assignment to exercise groups; assessment of both physiologic and functional status outcomes; follow-up beyond the completion of supervised exercise; and a large sample size (Total N = 180).

Accidental Falls↗

PubMed1991

Torque development in isokinetic training.

Twenty men were randomized into three groups that performed maximal isokinetic knee extensions five days a week for 12 weeks; a fourth group was a control group. The training protocol was different for the opposite lower extremity of each subject, such that subjects in group I trained at 36 degrees/sec with 20 or 60 repetitions, group II did 20 repetitions at 36 degrees/sec with one limb and 60 repetitions at 108 degrees/sec contralaterally, and group III trained at 108 degrees/sec with 20 or 60 repetitions. Group IV did no training. Bilateral pretraining and posttraining vastus lateralis muscle biopsies were done, and maximal torque-velocity tests (0 degrees to 234 degrees/sec at 18 degrees/sec steps) were performed every two weeks. The muscle biopsies were examined for muscle-fiber area and enzyme activity. Statistical analysis of the torque-velocity curves showed that subjects who trained at 36 degrees/sec made significant overall gains in torque and significantly greater torque gains than those training at 108 degrees/sec. Torque gains were not made uniformly during the 12 weeks of training; they occurred primarily during the initial 4 to 8 weeks. There were no significant increases in muscle-fiber areas in response to training, but there were increases in glycolytic and mitochondrial enzyme activities. These findings suggest that the critical variable for developing strength (maximal torque), at least within the context of isokinetic training, is the amount of torque developed during training.

Adenosine Triphosphatases↗

PubMed1991

Heterotopic ossification and peripheral nerve entrapment: early diagnosis and excision.

Heterotopic ossification can occur in neurologic disorders, burns, musculoskeletal trauma, and metabolic disorders. In addition to producing the complications of contracture, skin breakdown, and pain, it can cause peripheral nerve entrapment. Nerve entrapment due to heterotopic ossification may be misdiagnosed, and it is difficult to evaluate and treat without recurrence. Computed tomography is especially useful in localization before surgical release of the entrapped nerve. Resection of heterotopic ossification can be successful using disodium etidronate to decrease the risk of recurrence, and resection can improve range of motion and nerve function. Two case studies of nerve entrapment due to heterotopic ossification are presented with the results of computed tomography localization, successful resection, and long-term follow-up. Clinicians should be aware of this complication and the potential for rapid nerve injury. If heterotopic ossification is causing clinically significant peripheral nerve entrapment, early surgical treatment may be indicated, and may be successful.

Adult↗

PubMed1991

Footwear and posture. Compensatory strategies for heel height.

The belief that wearing high-heeled shoes increases lumbar lordosis is firmly ingrained in clinical folklore. Proponents of negative heel footwear argue that because high positive heels increase the lumbar lordosis, negative heels will decrease the lumbar lordosis. Quantitative documentation of the assumption regarding high heels is not to be found in the literature, although sporadic attempts to prove this assumption have been made throughout the 20th Century. Although other effects, such as decreased gait speed and step length, and increased knee flexion at heel strike have been found in more than one study, no increase in lumbar lordosis has been found. Where an actual decrease in lordosis has been found, authors tend to explain it away as inconsistent with what every clinician feels that he or she has observed. We felt it appropriate, then, to conduct both a static and a dynamic study to assess the effects of heel height on lumbar spine and lower limb joint kinematics in the sagittal plane, as well as other strategies to compensate for heel height. The results indicate that the greatest compensation is at the ankle and knee. Where a significant effect occurred in the lumbar spine (males, dynamic study), high heels decreased the lumbar lordosis, i.e., resulted in less swayback rather than more.

Adolescent↗

PubMed1991

Shoulder subluxation in hemiplegia: effects of three different supports.

Shoulder subluxation in hemiplegia is a difficult problem to manage and it may be associated with pain and other complications. Measurements taken from x-rays have been used to obtain objective measures of shoulder subluxation, but have not been used to compare the effects of different shoulder supports. This study used x-ray measurements to evaluate different shoulder supports for subluxation in hemiplegia and to see if there was a significant difference between the Harris hemisling and the Bobath sling. The Harris hemisling gave good vertical correction of subluxation and compared closely to the uninvolved shoulder. The Bobath sling did not correct the subluxation as well, and the mean difference between the two slings was significant. The arm trough or lap board was less effective and tended to overcorrect. The Harris hemisling and arm trough or lap board had horizontal measurements similar to the uninvolved shoulders. The Bobath sling, however, distracted the glenohumeral joint horizontally and was more variable. The mean horizontal difference between the Harris hemisling and the Bobath sling was significant. These results support the effectiveness and specificity of shoulder support to decrease subluxation after hemiplegia.

Aged↗

PubMed1989

Hypnotherapy as an adjunct to narcotic analgesia for the treatment of pain for burn debridement.

This paper presents a hypnotherapeutic intervention for controlling pain in severely burned patients while they go through dressing changes and wound debridement. The technique is based on Barber's (1977) Rapid Induction Analgesia (RIA) and involves hypnotizing patients in their rooms and having their nurses provide posthypnotic cues for analgesia during wound cleaning. Five subjects who underwent hypnotherapy showed reductions on their pain rating scores (Visual Analogue Scale) relative to their own baselines and to the pain curves of a historical control group (N = 8) matched for initial pain rating scores. Although the lack of randomized assignment to experimental and control groups limited the validity of the results, the findings provide encouraging preliminary evidence that RIA offers an efficient and effective method for controlling severe pain from burns.

Adult↗

PubMed1987

The role of the biomechanics laboratory in the analysis of the gait of individuals with arthritis.

The function of a biomechanics laboratory is to measure those aspects of an individual patient's performance that cannot be quantitatively assessed in the clinical setting. Essential equipment provides the ability to measure gait events, ground reactive forces, kinematics (movement of the body and its segments in 3 dimensions), electromyographic activity, and oxygen consumption. A minicomputer with video screen is required to process the data and allow visual checks of the functioning of the system. Such things as moments around joints and deforming forces may be calculated from the measured variables. Illustrations are given of a schematic laboratory system, computer generated stick diagrams, real-time changes in forces, moment-arms, moments, and excursions, in addition to the alteration of these variables in tibial nerve paralysis and degenerative arthritis of the knee.

Arthritis↗

PubMed1986

Gait abnormalities in peroneal nerve paralysis and their corrections by orthoses: a biomechanical study.

Stroke, brain injury, incomplete spinal cord injuries, and peripheral neuropathies frequently result in dysfunction of the foot dorsiflexors and evertors. A controlled examination of aspects of these disabilities was conducted with normal volunteers who underwent a temporary peroneal nerve block. The effects of peroneal nerve paralysis were analyzed to quantitatively describe the resulting gait abnormalities and to assess the effectiveness of orthoses in restoring a normal gait pattern. Kinematic and kinetic measurements were made during normal ambulation, ambulation with a right peroneal nerve paralysis, and ambulation with a paralysis and an ankle-foot orthosis (AFO) with three different adjustments: a posterior stop set in 5 degrees plantarflexion, a posterior stop set in 5 degrees dorsiflexion, and spring-assisted dorsiflexion. The peroneal paralysis produced abnormalities during both the stance and swing phases of gait. During early stance there was a decrease in the length of the heelstrike phase and a reduction in the peak plantarflexion moment (p less than 0.01). During midstance there was an increase in the range of inversion-eversion achieved suggesting medial-lateral instability (p less than 0.01). The second vertical force peak and the aft-shear force peak were reduced (p less than 0.05) as were the peak dorsiflexion moment and the opposite steplength (p less than 0.01). These reductions are believed to be due to medial-lateral instability during pushoff. Subjects demonstrated a steppage gait during swing phase and increased inversion just prior to heelstrike (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1985

Ankle-foot orthoses: effect on gait abnormalities in tibial nerve paralysis.

To study the biomechanical effects of gastrocnemius-soleus dysfunction and its potential remediation, the gait patterns of six able-bodied young adults were analyzed before and after induced temporary tibial nerve paralysis. Ambulation with the tibial nerve block was performed with and without the assistance of an ankle-foot orthosis (AFO) with a rigid anterior stop adjusted to either 5 degrees plantarflexion or 5 degrees dorsiflexion. The gait abnormalities resulting from tibial nerve paralysis include delayed advancement of the center of pressure, delayed ipsilateral heeloff and early contralateral heelstrike, decreased steplength, decreased ankle dorsiflexion moment, and increased knee flexion moment. This study provides quantitative information on the degree to which these abnormalities were corrected by appropriately adjusted AFOs. When using an AFO with an anterior stop, subjects with tibial nerve paralysis had improved advancement of the center of pressure (p less than 0.01). The body's ground reactive force line moved forward more normally, pivoting over the metatarsal head area and raising the heel earlier than observed with uncorrected tibial nerve paralysis, thus approximating the normal ankle dorsiflexion moment, normal timing of gait events, normal advancement of the hip, and normal steplength. The AFO with the anterior stop set at 5 degrees plantarflexion was more effective in restoring the values to normal than the AFO with the anterior stop set at 5 degrees dorsiflexion, but still did not consistently achieve the normal values. Only by using the AFO with the anterior stop set at 5 degrees plantarflexion was the increased knee flexion moment observed during the block reduced to normal levels (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1985

Gait abnormalities in tibial nerve paralysis: a biomechanical study.

Gastrocnemius-soleus dysfunction is a frequent result of cauda equina lesions and peripheral neurophathies and of stroke and brain injury. Temporary tibial nerve paralysis constitutes a comparable laboratory condition which allows the controlled examination of aspects of these disabilities. The biomechanical effects of temporary tibial nerve paralysis in six normal young adult volunteers were examined to quantitatively define the gait abnormalities resulting from gastrocnemius-soleus paralysis and to provide a basis for the assessment of the effectiveness of different orthotic designs in restoring a normal gait pattern. The motion of the right lower extremity, ground reactive forces acting on the right lower extremity, timing of gait events and step length were recorded, first during normal ambulation and then during ambulation after a right tibial nerve block. Step length was reduced bilaterally after the nerve block (p less than 0.005); the reduction was greater for the left (unblocked) step than for the right (blocked) step (p less than 0.005). Right heeloff was delayed until the time of left heelstrike in all subjects after the right tibial block. Right heeloff occurred later (p less than 0.005) while left heelstrike occurred earlier than normal (p less than 0.005). The shorter left step length and earlier left heelstrike resulted from a reduction in the forward progression of the right hip (p less than 0.001). When subjects were deprived of the plantarflexion activity necessary to counteract dorsiflexion moments at the ankle, they delayed the forward progression of the center of pressure (p less than 0.001) to avoid the unstable collapse of the foot into dorsiflexion.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1979

Effect on maximal strength of submaximal exercise in Duchenne muscular dystrophy.

Four Duchenne muscular dystrophy patients, with quadriceps of at least antigravity strength, exercised one quadriceps submaximally 4 or 5 days per week for six months. The exercise was done under supervision and consisted of extending one knee from 90 degrees to full extension using the Cybex isokinetic exerciser. The other side was not exercised at all. The two sides were tested for maximal isokinetic strength monthly for twelve months and at 18 and 24 months after the beginning of the study. On the average, the exercised leg had a greater maximal torque both during and after the exercise period until the torques on both sides decreased to zero. The results indicate that submaximal exercise has no negative effect and may be of limited value in increasing strength in Duchenne muscular dystrophy.

Child, Preschool↗