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Biomedical subjects

D Bourbonnais

Publications and source records attributed to D Bourbonnais.

At least 19 recordsLinked to original sources
PubMed2001

Effect of seat cushion on dynamic stability in sitting during a reaching task in wheelchair users with paraplegia.

OBJECTIVES: To examine the effects of seat cushions on dynamic stability in sitting during a controlled reaching task by wheelchair users with paraplegia. DESIGN: A randomized, controlled test. SETTING: Rehabilitation center. PARTICIPANTS: Nine wheelchair users with paraplegia. INTERVENTIONS: Three types of cushions--an air flotation, a generic contoured, and a flat polyurethane foam--were tested during a controlled reaching task in ipsilateral and contralateral directions, at 45 degrees from the sagittal plane in the anterolateral direction. Center of pressure (COP) coordinates were monitored by using a pressure measurement system as well as a force platform under seat. MAIN OUTCOME MEASURES: Trajectory of COP, maximal distance covered by COP, maximal velocity of COP; and the index of asymmetry between right and left maximal pressure under ischial tuberosities. RESULTS: The generic contoured cushion allowed the COP to cover significantly (p <.02) a larger distance (81 +/- 28mm) when compared with the air flotation (63 +/- 25mm) or the flat foam (61 +/- 29mm) cushions. The COP velocity was significant (p <.05) for the generic contoured cushion (.14 +/-.05m/s) versus the air flotation (.10 +/-.04m/s) or the flat-foam (.10 +/-.03m/s) cushions. The index of asymmetry was higher for the generic contoured and the flat foam cushions. During reaching, maximal pressure under ipsilateral ischial tuberosity was significantly higher for the flat foam (275 +/- 70mmHg) and the generic contoured (235 +/- 81mmHg) cushions, when compared with the air flotation cushion (143 +/- 51mmHg). CONCLUSION: Seat cushions can significantly affect sitting balance during reaching tasks. This study provided an objective method to assess the dynamic stability of wheelchair users when they perform activities of daily living requiring reaching. These findings have implications for wheelchair seating recommendations, especially seat cushion selection.

Activities of Daily Living↗
PubMed2001

Effects of upper limb unilateral isometric efforts on postural stabilization in subjects with hemiparesis.

OBJECTIVE: To characterize postural stabilization during a progressive unilateral isometric abduction of the upper limb in a seated position in healthy subjects and subjects with hemiparesis. DESIGN: Convenience sample. SETTING: University secondary care rehabilitation center. PATIENTS: Twelve patients with hemiparesis and 12 subjects without neurologic disorder. INTERVENTIONS: Subjects were seated on a forceplate, with forearms fixed in cuffs mounted on a force transducer. Two trials per side of isometric abduction of arm were conducted. The orthogonal force and torque exerted was measured for each arm. MAIN OUTCOME MEASURES: Forces at the upper limbs and at the seat, global motor performance, spasticity of upper limb, grip force, and dexterity. RESULTS: Results of analyses of variance showed differences in the magnitude of the contralateral limb forces generated by subjects with hemiparesis and healthy subjects (p <.05). Normalized contralateral forces in the nonparetic upper limb associated with paretic isometric efforts were higher than those associated with nonparetic efforts and higher than those associated with efforts in healthy subjects. CONCLUSION: These results suggest that postural stabilization during isometric efforts is impaired in subjects with hemiparesis.

Adult↗
PubMed2000

Effects of upper and lower limb static exertions on global synkineses in hemiparetic subjects.

OBJECTIVES: Global synkineses are nonpurposive pathological involuntary muscle activities or movements elicited at several or all of the joints of the affected limb or limbs during voluntary forceful resisted contractions. The purpose of this study was to assess the effect of upper and lower limb exertions on manifestations of upper limb global synkineses in hemiparetic subjects. DESIGN: Involuntary muscle activities on the affected upper limb of 11 hemiparetic subjects and on the left or right upper limb of 10 control subjects were recorded using surface electromyography during successive bilateral maximal ankle exertions and during contralateral grips. RESULTS: Significant differences in the level of involuntary electromyography (EMG) activities were observed between experimental conditions (ANOVAs, p < 0.05). EMG levels in hemiparetic subjects were significantly higher during contralateral grip tasks than during the ankle exertions. CONCLUSION: These results suggest that upper limb global synkinases are more prevalent in specific tasks and that this task specificity may reflect the neurophysiological mechanisms involved in the generation of global synkinases.

Adult↗
PubMed1999

Plantarflexor weakness as a limiting factor of gait speed in stroke subjects and the compensating role of hip flexors.

OBJECTIVE: To determine, using the Muscular Utilization Ratio (MUR) method, whether plantarflexor weakness is among the factors preventing stroke subjects from walking at faster speeds. Potential compensations by the hip flexors were also examined. DESIGN: A convenience sample of 17 chronic stroke subjects in a context of a descriptive study. BACKGROUND: Gait speed is correlated with the residual strength of the muscles involved in gait in stroke subjects. However, it has not been established if this residual strength limits gait speed. METHODS: Kinetic and kinematic data for comfortable and maximal gait speeds were collected on the paretic side, and were used to determine the moments in plantarflexion (mechanical demand: MUR numerator) during the push-off phase. The maximal potential moment (MUR denominator) of the plantarflexors during gait was predicted using an equation derived from dynamometric data collected with a Biodex system. The MURs of the plantarflexors were then calculated at every 1% interval of the push-off phase. The pull-off phase of gait and the hip flexor strength were also examined. RESULTS: Ten subjects of the sample had a MUR value between 80 and 150% at maximal gait speed. These subjects produced the lowest peak torques in plantarflexion. Each of the four fastest subjects of this group had a large hip flexion moment during the pull-off phase of gait and produced high hip flexion torque values on the dynamometer. Each of the seven remaining subjects had a MUR value under 70% when they walked at maximal speed. CONCLUSIONS: Weakness of the plantarflexors should be considered as one factor limiting gait speed in 10 hemiparetic subjects. Some subjects with weak plantarflexors could walk rapidly because they compensated with the hip flexors. For the remaining stroke subjects, factors other than weakness of the plantarflexors have to be considered in order to explain the reduction in their gait speed.

Adolescent↗
PubMed1999

Description of a new motor re-education programme for the paretic lower limb aimed at improving the mobility of stroke patients.

OBJECTIVE: To describe and examine the feasibility of a new treatment approach for the paretic lower limb and to explore its effectiveness in one chronic hemiparetic stroke subject. DESIGN: Case report. The treatment was conducted three times per week over a period of six weeks. The mobility of the patient was assessed prior to the treatment, at the end of the treatment and at a six-week follow-up. SETTINGS: The study was carried out at the research centre of the Institut de réadaptation de Montréal. The treating therapist was an experienced rehabilitation professional as was the assessor, who worked at a different rehabilitation centre. INTERVENTIONS: The motor re-education programme was based on the use of a static dynamometer that measures the linear external forces produced at the ankle level. A computer program provided the subject with constant feedback on the direction and intensity of the applied force. In each treatment session, the subject was asked to produce several submaximal efforts in 16 specific directions. Both the intensity and the number of repetitions were gradually increased. OUTCOME MEASURES: In addition to force production measurements, three clinical assessments of mobility were used: the Timed 'Up and Go', the comfortable gait speed and a 2-minute walk test. RESULTS: The maximal static linear forces produced by the subject increased through the treatment for all directions of effort, but differences were observed amongst directions. During the treatment programme, the subject improved his performance at the three clinical assessments. Even if some of the functional gain was lost at the follow-up, the mobility was still considerably improved as compared to baseline values. CONCLUSION: This study demonstrated the applicability of the treatment programme to a stroke subject. The results seem very promising and encourage further investigation in order to assess more rigorously the effectiveness of this new approach.

Adult↗
PubMed1999

Maximal grip force in chronic stroke subjects and its relationship to global upper extremity function.

OBJECTIVES: Previous studies have shown that recovery of recordable grip strength in acute stroke subjects is one of the most sensitive assessments of initial upper limb recovery and a good prognostic factor for latter recovery. The objectives of this study were to test the reliability of maximal voluntary grip force (MVGF) measures and evaluate the relationship between paretic grip strength deficit and paretic upper extremity function in chronic stroke subjects. DESIGN: Over a three-week period, bilateral MVGF was assessed three times with a modified strain gauge dynamometer in 15 chronic stroke subjects and 10 control subjects. The paretic MVGF deficit was expressed in relation to the MVGF of the nonaffected hand. OUTCOME MEASURES: Upper extremity function in stroke subjects was measured using the Fugl-Meyer, the upper extremity performance test for the elderly (TEMPA), Box and Block and finger-to-nose tests. RESULTS: MVGF measures in both groups of subjects demonstrated good reliability (intraclass correlation, ICC >0.86) and low standard error measurements (SEM). The paretic MVGF of the stroke subjects was greatly impaired in comparison to the control subjects. Results of linear and quadratic regressions analyses show that this impairment was significantly correlated (p <0.01) with the performance of the stroke subjects on the four upper extremity function tests. The percentages of variances explained by the MVGF deficit on all four upper extremity tests varied from 62% to 78% for the linear regressions and from 72% to 93% for the quadratic regressions. CONCLUSIONS: These results suggest that the paretic maximal grip strength, normalized with the maximal grip strength on the nonaffected side, appears to be a valuable outcome measure of upper extremity function in chronic stroke subjects.

Adult↗
PubMed1998

The interrater reliability of force measurements using a modified sphygmomanometer in elderly subjects.

BACKGROUND AND PURPOSE: Physical therapists working with elderly people require an instrument that provides reliable force measurements and can be used in a clinical setting. The modified sphygmomanometer has been identified as potentially fulfilling these requirements, yet there is an absence of research on the reliability of measurements taken with this instrument on elderly patients. This study was undertaken to investigate the interrater reliability of force measurements, in a group of elderly subjects, using a modified sphygmomanometer. SUBJECTS: Thirty-six hospitalized subjects (mean age=75.28 years, SD=9.43, range=62-95) participated in the study. METHODS: With the modified sphygmomanometer, 3 examiners evaluated the isometric force of the elbow extensors and hip extensors using a break test and a make test, respectively. RESULTS: Intraclass correlation coefficients (2,1) reflecting reliability were .87 for the elbow extensors and .65 for the hip extensors. The estimation of the components of variance for hip extensors revealed that these results were due in part to the raters but that random error contributed to a much larger extent. CONCLUSION AND DISCUSSION: The modified sphygmomanometer appears to be practical to use, and the high correlations found in this study for the elbow extensors suggest that reliable measurements can be obtained with this instrument. Further research is needed, however, to specify the manner in which the modified sphygmomanometer can be used when assessing different muscle groups.

Aged↗
PubMed1998

A static dynamometer measuring simultaneous torques exerted at the upper limb.

The majority of available dynamometers are designed to measure force or torque in one specific direction, one joint at a time. For the quantification of motor incoordination in neurological patient populations, these dynamometers provide limited information about the global behavior of the limb under investigation. This report describes the potential use and function of a static dynamometer measuring torques exerted simultaneously at the shoulder (flexion-extension, abduction-adduction, internal-external rotation), elbow (flexion-extension), and forearm (pronation-supination). Orthogonal forces were measured at the arm and wrist using strain gauge transducers interfaced with a laboratory computer. The lever arms were specified to a software program and the joint torques were calculated in real time according to static equilibrium equations. The use of the dynamometer is illustrated by characterizing for one hemiparetic subject, the joints torques recorded at the shoulder, elbow, and forearm during isolated submaximal grip exertions at different force levels on both sides. The torques generated at the shoulder, elbow and forearm during the hand grip tasks on the affected side were significantly higher than those obtained on the nonaffected side and increased with the grip force level. These differences probably reflect the loss of movement selectivity observed following a lesion in the central nervous system. Further studies are currently being undertaken in neurological patient populations to characterize and quantify motor deficits using this dynamometer. As a long term goal, we hope that the method and technologies described here will contribute to the evaluation and rehabilitation of these populations.

Biofeedback, Psychology↗
PubMed1997

Characterization of global synkineses during hand grip in hemiparetic patients.

OBJECTIVE: Global synkineses are defined as nonpurposive associated movements on the involved side of hemiparetic subjects that are triggered during a voluntary movement. The purpose of this study was to characterize the intensity and pattern of upper limb global synkineses in hemiparetic subjects with a static biarticular dynamometer and electromyography during maximal progressive hand grip on the unaffected side. DESIGN: Survey, convenience sample. SETTINGS: University secondary care rehabilitation center. DATA SET: Global synkineses (ie, torques and electromyographic activities) in patients with severe (n = 8) and moderate (n = 7) deficits in motor performance, as evaluated by the Fugl-Meyer assessment, were compared with those obtained in a group of healthy subjects (n = 11). Clinically the subjects from the severe deficit group were more spastic and showed less strength at the elbow than the subjects from the moderate deficit group. RESULTS: Results of analyses of variance showed significant increases of shoulder torque in flexion and internal rotation, and elbow torque in flexion, with increasing force exertion during contralateral hand grip in subjects with severe deficits (p < .05). Furthermore, in these subjects increases of electromyographic activity were also observed in biceps brachii, brachioradialis, and triceps brachii muscles with increasing hand grip force levels. In contrast, no significant torques or electromyographic increases were observed in subjects with moderate deficits and in control subjects during contralateral hand grip exertions. CONCLUSION: These results provide a quantitative assessment of the kinematic and electromyographic patterns of global synkineses and their correlates with clinical observations. Within the limits of the experimental results presented in this study, it is suggested that global synkineses result from contralateral overflow of the voluntary command to hyperexcitable motoneuron pools.

Adult↗
PubMed1997

Dynamometric assessment of the plantarflexors in hemiparetic subjects: relations between muscular, gait and clinical parameters.

The aims of this study were to investigate, in 16 subjects with hemiparesis, the plantarflexor muscle performance of the paretic side and to determine the level of the relationships between muscular parameters, clinical measures and gait performance. A Biodex dynamometric system was used to evaluate static and dynamic torques, power and maximal rate of tension development of the plantarflexor muscles. The clinical measures included the Fugl-Meyer assessment (FMA), the "Up & Go" test and an evaluation of ankle muscle tone. Velocity, cadence, stride length and gait cycle duration were determined for each subject at both comfortable and maximal safe speeds using foot contacts and videographic data. Results indicated that dynamometric values produced by the hemiparetic subjects were reduced in comparison to those reported for healthy subjects. Their torque-angle curves had a curvilinear shape which indicated pronounced decrease of torque for plantarflexion efforts at the beginning of the movement. Torques produced at different velocities of testing did not demonstrate significant differences (MANOVAs: p > 0.05) but power values were significantly different. Results also showed that all the selected muscular parameters (torque, power and maximal rate of tension development) were moderately to highly interrelated (0.65 < r < 0.94; p < 0.01) suggesting that a common factor of muscular performance was assessed. Furthermore, the dynamometric data were significantly associated with some of the clinical measures (sensation and lower limb motor control scores of the FMA) but were not related to the gait variables (Pearson's r < 0.45; p > 0.05). This last finding suggests that the relationship between plantarflexor strength and the level of gait performance in adults with stroke is complex. The relationship may be influenced by other factors such as muscular compensations within and between limbs and motor control impairments.

Adolescent↗
PubMed1997

Effects of transcutaneous electrical nerve stimulation on the H-reflex of muscles of different fibre type composition.

Differential effects of repetitive stimulation of low threshold afferents on both the recruitment threshold and motoneuronal excitability of type I and type II motor units have been demonstrated. The present study was aimed at further investigating the differential effects of 30 minutes of transcutaneous electrical nerve stimulation (TENS) on the H-reflex amplitude (Hmax/2) of the Soleus (SO), gastrocnemius lateralis (GL) and medialis (GM) muscles. Eleven healthy subjects were tested in order to evaluate the effects of TENS on either the common peroneal (CPN), saphenous or sural nerve. The experimental session consisted of three consecutive 45 min periods. Within each of these periods, H-reflexes were recorded before, during and after the TENS was applied. It was hypothesized that repetitive low threshold afferent stimulation would either have inhibitory or facilitatory effects on the H-reflex amplitude of the SO or gastrocnemii muscles respectively. Non-parametric Friedman ANOVAs revealed a significant tendency (p < 0.05) toward inhibition of the H-reflex amplitude of the SO and GL muscle during TENS applied over either the CPN or sural nerve, as well as that of the GM during repetitive stimulation of the saphenous nerve. Although the present study failed to reveal any differential effects of TENS on the H-reflex amplitude of muscle on different fibre type content, the significant decrease in H-reflex observed on the triceps surae muscles during TENS applied over the CPN might have promising clinical outcomes for hyperreflexive subjects.

Adult↗
PubMed1996

A mechanical model to study the relationship between gait speed and muscular strength.

This study proposes a mechanical model to investigate the relationship between gait speed and strength of the ankle plantarflexor muscles. The model calculates the muscular utilization ratio (MUR) of the plantarflexor muscles during gait by comparing the plantarflexion moment used while walking to the maximal moment of the plantarflexors estimated from dynamometric measurements. To verify the model, MURs of the plantarflexor muscles were calculated for five healthy subjects and one hemiparetic subject walking at different speeds (slow, self-selected, and fast). Generally, the results of the healthy subjects revealed that MURs increase with an increasing gait speed: average (+/-SD) peak values of MUR reached 58.8% (+/-18.5), 65.6% (+/-17.2) and 71.0% (+/-17.8) for the slow, self-selected, and fast speeds, respectively. The average peak value of MURs at the self-selected speed corresponds to values reported in electromyographic studies of the plantarflexor muscles. At self-selected gait speed, the hemiparetic subject presented a higher peak MUR (80.5%) of the plantarflexors and a lower gait velocity when compared to healthy subjects. For the hemiparetic subject, peak values of MUR of the plantarflexor muscles at maximal walking speed reached 100% suggesting that full activation of the plantarflexors had been reached preventing him from walking faster. From these preliminary results, it appears that MURs calculated by the proposed model are sensitive to the mechanical demands imposed on a group of muscles during a task (eg., increase in gait speed) and to change in the maximal plantarflexor's strength (eg., weakness). The proposed model seems to have the potential to demonstrate whether muscle weakness limits maximal gait speed in hemiparetic subjects. However, considering the complexity of gait speed regulation in hemiparetic patients, the model should be tested on a large number of hemiparetic subjects.

Adolescent↗
PubMed1996

Performance of the 'unaffected' upper extremity of elderly stroke patients.

BACKGROUND AND PURPOSE: The main objective of this study was to compare the sensorimotor performance of the unaffected upper extremity (UE) of elderly stroke patients with that of healthy elderly people. METHODS: The group of stroke patients was composed of 43 hemiplegic/paretic subjects who had had a cerebrovascular accident at least 6 months earlier. They were > or = 60 years old, were right-handed before the stroke, had visual perception within normal limits, and showed no major cognitive impairments. A group of 43 healthy subjects matched for dominance, age, and sex was used for comparison. The main parameters of the performance of the unaffected UE of the stroke subjects and of the same side of the healthy subjects were measured with valid, reliable instruments. Some variables potentially related to the unaffected UE were also measured: affected UE motor function, functional independence, length of time since the stroke, self-perceived health status, activity level, and hand anthropometry. RESULTS: Statistical analyses showed significant deficits in the unaffected UE of hemiplegic/paretic subjects compared with normal subjects with regard to the following parameters: gross manual dexterity, fine manual dexterity, motor coordination, global performance, and kinesthesia (P < .01 to P < .0001). No significant clinical or statistical difference was found for grip strength (P < .81), static and moving two-point discrimination (P = .21 and P = .12), or touch/pressure threshold (P < .91). CONCLUSIONS: Many factors (frequency of use of the unaffected hand, sensorimotor interaction tasks, severity of the deficits in corticifugal projections, and deficits in postural stabilization) could interact to provide the clinical picture obtained in the present study.

Aged↗
PubMed1996

Effects of transcutaneous electrical nerve stimulation on H-reflex and spinal spasticity.

The purpose of this study was to investigate the short-term effects of transcutaneous electrical nerve stimulation (TENS; 99 Hz; 250 ms pulses) on H-reflex and spinal spasticity. Considering the reflex hyperexcitability commonly displayed in spinal cord-injured subjects, it was hypothesized that repetitive low threshold afferent stimulation would have an inhibitory effect on the triceps surae H-reflexes which could also be reflected by a decrease in plantarflexor spasticity. Clonus, Achilles tendon reflex and modified Ashworth evaluations were performed on 14 spinal cord-injured subjects prior to and after 30 minutes' application of TENS. Non-parametric statistical analyses (n = 14; alpha = 0.05) failed to reveal significant effects of TENS on H-reflex amplitude. However, there was a significant decrease in scores for the Achilles tendon reflex and the modified Ashworth test. The clonus score decreased in most subjects post-TENS, although not in a statistically significant manner. The present pilot results thus suggest that TENS appears to be effective in reducing spinal spasticity, as measured clinically.

Adult↗
PubMed1994

Absence of consistent effects of repetitive transcutaneous electrical stimulation on soleus H-reflex in normal subjects.

Our purpose was to determine the effects of transcutaneous electrical nerve stimulation (TENS) on the soleus H-reflex amplitude in normal subjects. Eleven subjects were tested in five experimental sessions, the purpose of which was to compare the effects of 30 minutes of TENS delivered at either 50 or 99Hz (250 microseconds pulses) on a mixed (common peroneal nerve or CPN) versus a sensory (sural) nerve. The soleus H-reflex was elicited according to the classic protocol of Hugon (1973). Control values (Hctrl) were measured for 5 minutes prior to and for 10 minutes after the TENS was administered at twice the sensory threshold. No statistically significant session (treatment) effects (two-way ANOVAs for repeated measures; alpha = 0.05) resulted from the stimulation of the CPN or the sural nerve at 50 or 99Hz. However, although no specific trends were shown across all subjects, there was a definite tendency towards inhibition (> or = 10% Hctrl) of the H-reflex in 63% of the subjects after 30 minutes of TENS at 99Hz over the CPN, and in 50% of the subjects when TENS was applied over the sural nerve at 99Hz. The inherent variability of the H-reflex amplitude in normal subjects as well as the use of different stimulation paradigms and TENS parameters could explain the controversial findings present in the literature.

Adult↗
PubMed1993

An ascending spinal pathway transmitting a central rhythmic pattern to the magnocellular red nucleus in the cat.

The activity of cells in the magnocellular red nucleus (RNm) was recorded extra- and intracellularly in the curarized thalamic cat performing fictive locomotion. The locomotor episodes were detected from the rhythmic activity recorded in the motor nerves of the contralateral hindlimb. It was confirmed that, during fictive locomotion, a large proportion of the rubrospinal cells (56% in our sample) exhibit a rhythmic pattern of activity which is synchronized with the efferent spinal motor nerve activity. On the basis of the intracellular recordings it was established that phases of intense synaptic activity with mixed excitatory postsynaptic potentials (EPSPs) and inhibitory postsynaptic potentials (IPSPs) are involved in this rhythmicity. After eliminating the cerebellar input to the RNm, it was observed that the cells still received intense excitatory and inhibitory inputs, resulting in a continuous modulation of their membrane potential, due to the occurrence of EPSPs and IPSPs. During fictive locomotor-like activity and after elimination of the cerebellar afferents to the RNm, it was observed that the spontaneous PSPs in RNm cells (in the case of 45% of the cells) were organized in repetitive subthreshold bursts occurring in phase relationships with the activity recorded in the motor nerves. Some extracellularly recorded cells (12%) showed a rhythmic firing pattern. It is generally recognized that, in the thalamic cat preparation, the locomotor pattern observed in efferent nerves originates from the central pattern generator (CPG) of the spinal cord. It therefore seems likely that the rhythmicity observed here in the RNm may originate from the spinal CPG and be transmitted through the spino-rubral pathway ascending in the ventral part of the cord. It is concluded that the spino-rubral pathway may transmit both somatosensory information and corollary discharges relating to the activity of the spinal CPG for locomotion.

Animals↗
PubMed1993

A static dynamometer measuring multidirectional torques exerted simultaneously at the hip and knee.

The function of a static dynamometer measuring torques exerted simultaneously in the different anatomical planes of the hip (flexion-extension, abduction-adduction and internal-external rotation) and knee (flexion-extension) is described. Muscular torques were calculated in real time using a desktop computer from measurements of orthogonal forces applied at two locations and the lever arm values measured in each subject. The reliability of the force transducers was explored by examining their output, using calibrated weights, on three different days. The results were identical over this period of time, indicating that the transducers are highly reliable. A mechanical simulator of a lower limb was constructed to generate specific or combined torques of known values at the hip and knee. The torques measured by the dynamometer were found to be highly concordant with the known torques applied by the simulator, indicating that the torque measurements were valid. The usefulness of the dynamometer is demonstrated by evaluating the activity of the rectus femoris and biceps femoris muscles during static efforts exerted in various directions at the hip. In addition, the mechanical action of biarticular muscles at the hip was evaluated by quantification of hip torques during efforts exerted at the knee. From these results, it has been concluded that the present biarticular and multidirectional dynamometer is a valid, reliable and precise instrument that may prove to be useful in evaluating the muscular function of the lower limb.

Biophysics↗