Evaluation of reflex- and nonreflex-induced muscle resistance to stretch in adults with spinal cord injury using hand-held and isokinetic dynamometry (original) (raw)
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Assessment of spasticity using isokinetic dynamometry in patients with spinal cord injury
Spinal Cord, 1999
Objectives: To determine the value of isokinetic dynamometric measurement of passive resistance in quantifying spasticity. Setting: Turkey. Methods: Thirty-three spastic spinal cord-injured patients and 14 age-matched normal individuals were studied. Five consecutive¯exion-extensions of the knee, abductionadductions of the hip, and dorsal-plantar¯exions of the ankle were performed at speci®c velocities (15, 30, 60, 90 and 1208/s) using a computerized isokinetic dynamometer set at the continuous passive motion mode. We recorded maximum torque and the sum of torque amplitudes for ®ve repetitions of each type of joint motion at all velocities. Results: Maximum torque values and the sum of torque amplitudes were both signi®cantly higher in spastic patients than in controls, and there was a positive correlation between torque values and Ashworth scores. There was no signi®cant linear increase in torque values associated with increasing velocity for any of the motions in either controls or patients. Conclusion: Isokinetic dynamometric measurement of passive resistance appeared to be a valuable tool for assessing and quantifying spasticity, as well as other types of hypertonus.
Quantifying muscle tone in spinal cord injury patients using isokinetic dynamometric techniques
Spinal Cord, 1996
The torque generated during a passive movement of the knee joint was used to quantify muscle tone in normal able-bodied subjects and spastic and flaccid spinal cord injury (SCI) subjects using a computerized isokinetic dynamometer. Maximum peak (Tmax) and the sum of four consecutive peaks (Tsum) were calculated for each velocity (30, 60, 120° Is) and for each phase (flexing or extending) separately and compared statistically using a one-way ANOV A. Statistical significance between groups was found in T max FLEXION (FLX) at 60 and 1200/s. Scheffe's tests revealed that the spastic group was significantly less than both the flaccid and normal groups, although the flaccid and normal groups were not significantly different from each other. The slopes of the linear regression curve of the torque-velocity data were found and compared statistically using a t-test for parallelism. In all parameters, the data increased in a linear fashion with increasing velocity of knee motion. The slope of the regression curve for the spastic group was significantly lower than that of the normal group for T max and was significantly lower than that of the flaccid group for Tsum while the slopes for the flaccid and normal groups were not significantly different. The ability of the entire set of variables to classify subjects into three groups (normal, spastic, and flaccid) was tested using discriminant analysis. By taking into account 7 of the 12 original variables, this multivariate technique correctly classified 100% of the spastic, 90% of the normal, but only 67% of the flaccid subjects. Separation of observations was between spastic and normal subjects was good, except for only one case. This feature could be useful when dealing with assessment of individual responses to therapeutic interventions aimed at modification of spasticity.
Spinal Cord, 2011
Study design: Between-groups design with repeated measures. Objective: To quantify spastic hypertonia in spinal cord-injured (SCI) individuals. Setting: Rehabilitative Center, Italy. Subjects: 29 individuals with a motor complete SCI (American Spinal Injury Association impairment scale grade A or B) and 22 controls. Methods: According to the modified Ashworth scale (MAS), patients were subgrouped as SCI-1 (MAS ¼ 1, 1 þ ) and SCI-2 (MAS ¼ 2, 3). Passive flexo-extensions of the knee were applied using an isokinetic device (LIDO Active) at 301, 601, 901 and 1201 s À1 . We measured the peak torque, mean torque (MT) and work. Simultaneous electromyography (EMG) was recorded from leg muscles. Results: At the speed of 1201 s À1 all SCI-2 patients presented EMG reflex activities in the hamstring muscle. All biomechanical parameter values increased significantly according to speed, but analysis of variance revealed a significant interaction between the angular velocity and group (F(d.f. 6, 138) ¼ 8.89, Po0.0001); post hoc analysis showed significantly greater torque parameter values in the SCI-2 group compared with the SCI-1 group and the control group at 901 and 1201 s À1 . Receiver operating characteristic curves showed that using peak torque values the probability of correctly classifying a patient into SCI-1 and SCI-2 was 95%, compared with 70% for MT and 68% for work. Conclusions: The isokinetic device is useful for distinguishing individuals with a high level of spastic hypertonus. Examination of EMG activity may help ascertain whether increased muscle tone is caused by reflex hyper excitability and to determine whether muscle spasm is present. Peak torque and simultaneous EMG assessment should be considered for the evaluation of individuals with SCI in the rehabilitative context, that is, in measuring therapeutic interventions.
The journal of spinal cord medicine, 2008
To examine the role of reflex activity in spasticity and the relationship between peak passive torque, Ashworth Scale (AS), and Spasm Frequency Scale (SFS) of the knee flexors and extensors during the measurement of spasticity using an isokinetic dynamometer in children with spinal cord injury (SCI). Eighteen children with chronic SCI and 10 children of typical development (TD) participated. One set of 10 passive movements was completed using an isokinetic dynamometer at 15, 90, and 180 degrees per second (deg/s) while surface electromyographic data were collected from the vastus lateralis (VL) and medial hamstrings (MH). Spasticity was clinically assessed using the AS and SFS. There were no significant differences in peak passive torque of the knee flexors and extensors at any velocity for children with SCI compared to children with TD. Children with TD demonstrated significantly more reflex activity of the MH during the assessment of knee flexor spasticity at all movement velociti...
2007
To examine the effects of purported fiber-type transformation following spinal cord injury (SCI), twitch contractile properties of the soleus, tibialis anterior (TA) and thenar muscles were examined in individuals with chronic (> 4 years) SCI. Furthermore, the force-frequency relationship, fatigue and posttetanic potentiation (PTP) of the paralyzed TA muscle were also evaluated. Nine adults with SCI (22-59 yrs; lesion level C3-T2) and 9 ageand gender-matched able-bodied controls (AB) participated in this study. On the first visit to the laboratory, the maximum twitch response for all three muscles was determined by delivering a series of single stimuli with gradually increasing intensity. For evaluation ofPTP, tetanic stimulation (100Hz) was applied to theTA for 5 seconds followed by single twitches delivered at 5 seconds after tetanus and then at 30 second intervals for 4 minutes posttetanus. On a second visit, the force-frequency relationship (FFR) and 15Hz fatigue of the T A ...
Medical engineering & physics, 2016
The interaction between muscle contractions and joint loading produces torques necessary for movements during activities of daily living. However, during neuromuscular electrical stimulation (NMES)-evoked contractions in persons with spinal cord injury (SCI), a simple and reliable proxy of torque at the muscle level has been minimally investigated. Thus, the purpose of this study was to investigate the relationships between muscle mechanomyographic (MMG) characteristics and NMES-evoked isometric quadriceps torques in persons with motor complete SCI. Six SCI participants with lesion levels below C4 [(mean (SD) age, 39.2 (7.9) year; stature, 1.71 (0.05) m; and body mass, 69.3 (12.9) kg)] performed randomly ordered NMES-evoked isometric leg muscle contractions at 30°, 60° and 90° knee flexion angles on an isokinetic dynamometer. MMG signals were detected by an accelerometer-based vibromyographic sensor placed over the belly of rectus femoris muscle. The relationship between MMG root me...
Annals of Biomedical Engineering, 2000
Frequency response characteristics of the ankle plantar flexors were studied in adults both with and without spinal cord injury ͑SCI͒ to determine how the muscle contractile properties change after SCI, and to see if there is a relation between the severity of spasticity and how the properties change. Ten controls and ten complete, chronic spinal cord injured subjects were tested, where the tibial nerve was stimulated electrically in a stochastic manner with the ankle fixed isometrically at various joint angles. A nonparametric linear frequency response function was derived, from which a secondorder transfer function was calculated. The contractile dynamics were then characterized by the three classic second-order parameters: gain, damping ratio, and natural frequency. We found that in subjects with low degrees of spasticity ͑as determined by clinical evaluation͒, the contractile dynamics presented the largest changes, in which the speed of contraction increased significantly while there were no statistical differences in the gains between the two groups. This similarity emerged even though there was noticeable atrophy in the SCI patient group. Differences between the controls and subjects with high levels of spasticity were markedly different, in that these SCI subjects had slower contractile speeds than the controls, but significantly lower gains. Moderately spastic subjects fell somewhere in between, where the speed of muscle contraction increased modestly yet the gain was significantly smaller than that of the control subjects. These findings indicate that in subjects with chronic spinal cord injury, the severity of spasticity can significantly influence the degree of change in muscle contractile properties. It appears that high degrees of spasticity tend to preserve contractile dynamics, while in less spastic subjects, muscle contractile properties may display faster response characteristics. © 2002 Biomedical Engineering Society.
Reduced Muscle Activity of the Upper Extremity in Individuals with Spinal Cord Injuries
International Journal of Environmental Research and Public Health
Compromised physical ability due to musculoskeletal impairment among spinal cord injury (SCI) patients is known to negatively affect their quality of life. It is essential to comprehensively understand the muscle strength of the upper extremity among patients with SCI to enhance muscle function and capacity to engage in an active lifestyle. The objective of this study was to evaluate the muscle strength of 15 upper extremity muscles among patients with SCI and compare the relative weakness of individual muscles to the control group. Seven male patients with SCI with ASIA impairment scale D and E and 33 males in the control group participated in this study. Each participant performed maximal voluntary contraction of individual muscles, and the electromyography data were recorded. The results showed that the majority of the upper extremity muscles (12 out of 15) showed considerable weakness (24 to 53%) relative to the control group. Furthermore, the relative strength (ranking) of indi...