PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Reflex, Stretch”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources
PubMed1982

Study of propriospinal interneuron system in man. Cutaneous exteroceptive conditioning of stretch reflexes.

Functional characteristics of the propriospinal interneuron system have been studied in 20 patients with clinically complete chronic transverse spinal cord injury by conditioning repetitively elicited Achilles tendon jerks with noxious electrical stimuli applied to the thoracic, lumbar, and sacral dermatomes. Such conditioning stimuli caused an increase of ipsilateral and contralateral Achilles tendon jerks except when they were applied to the ipsilateral plantar surface when they caused suppression. This effect is due to inhibition of the tested extensor motoneurons by the conditioning stimuli applied to the plantar surface. More generally the observed increase of Achilles tendon jerks can be explained by excitation spread from distant ipsilateral and contralateral thoracic, lumbar and sacral segments. It is likely that this effect is mediated by the fibers of the fasciculi proprii of the spinal cord as this system survives complete transection of the spinal cord.

Adolescent↗
PubMed1979

Coding process in human stretch reflex analysed by phase-locked spikes.

The Achilles tendon of man was tapped by triangular pulsatory waves with stimulus intervals from 10 to 100 Hz, while single motor unit spikes were recorded from the soleus muscle. The discharge probability of the motor unit spikes in relation to the triangular taps was analysed by means of cross-correlograms. A summation of the results of cross-correlograms of motor unit spikes with 10--100 Hz taps revealed one prominnet kernel, the primary correlation kernel. From the summated correlograms, it became clear that the mean width of the primary correlation kernel, the correlation time, was 8.3 +/- 2.5 msec. The correlation time is interpreted as representing the time-to-peak of the excitatory postsynaptic potential of an alpha-motoneuron.

Humans↗
PubMed2005

Reliability of elbow stretch reflex assessment in chronic post-stroke hemiparesis.

OBJECTIVE: To establish reliability of quantitative measures of elbow joint spastic hypertonia in post-stroke hemiparesis. METHODS: Nine subjects with post-stroke hemiparesis (mn duration: 42 months) were tested on three separate days. Biceps brachii and brachioradialis EMG were recorded during passive ramp-and-hold extensions applied at seven speeds between 30 and 210 degrees /s. EMG burst duration, onset position threshold, and burst intensity were used to evaluate reflex activity. Torque at 40 degrees of elbow flexion was used as a mechanical indicator of spastic hypertonia. RESULTS: Across speeds ICCs were consistent, means ranged between 0.63 and 0.85. Thus, relative reliability was fair to excellent for all parameters. Absolute reliability, determined using standard error of measurement expressed as a percentage of the mean score (%SEM), improved at higher speeds (> or = 120 degrees/s). CONCLUSIONS: These results establish reliability of reflex and mechanical measures of elbow spastic hypertonia post-stroke. The data demonstrate greater reflex detection at high speeds, indicating greater potential to document meaningful changes in these distinct aspects of spastic hypertonia following intervention. SIGNIFICANCE: Based on findings of this study, reliability was demonstrated using four parameters of reflex EMG and torque indicating measurement consistency across sessions. These observations motivate determination of requisite effect sizes for clinical trials that evaluate treatment outcome.

Aged↗