Velocity Determinants in Spastic Patients after Stroke-A Gait Analysis Study

INTRODUCTION

Gait velocity in spastic patients after stroke is both a life quality and mortality predictor. However, the precise biomechanical events that impair a faster velocity in this population are not defined. This study goal is to find out which are the gait parameters associated with a higher velocity in stroke patients with spastic paresis.

METHODS

The registries of a Gait analysis laboratory were retrospectively analyzed. The inclusion criteria were: trials of adult stroke patients with unilateral deficits. The exclusion criteria were: trials when patients used an external walking device, an orthosis, or support by a third person. Of the 116 initial patients, after the application of the exclusion criteria, 34 patients were included in the cohort, all with spatiotemporal, static and dynamic kinematic and dynamometric studies.

RESULTS

There was a correlation of velocity with cadence, stride length of the paretic (P) limb, stride length, and time of the P and non-paretic (NP) limb, double support time, all the parameters related to hip extension during stance phase, knee flexion during swing phase, and parameters related to ankle plantarflexion during stance phase.

CONCLUSIONS

The main gait analysis outcomes that have a correlation with speed are related to the formula velocity = step length × cadence or are related to stance phase events that allow the anterior projection of the body. The only swing phase outcome that has a correlation with speed is knee flexion. More studies are needed from gait analysis laboratories in order to point out the most relevant goals to achieve with gait training in spastic stroke patients.

An excitatory action of adrenaline, noradrenaline, and 5-hydroxytryptamine on the spinal cord

1. Fasciculation was produced in the trapezius and sternomastoid muscles of anaesthetized cats by adrenaline, noradrenaline and 5-hydroxytryptamine (5-HT) put into the cisterna magna. Isoprenaline, similarly applied, was ineffective.2. Each of the three active amines was without effect when applied for a second time after the fasciculation in response to the first application had passed off, but 5-HT was effective after adrenaline and, similarly, adrenaline after 5-HT.3. Fasciculation produced by adrenaline, but not by 5-HT, was inhibited by ergotamine or phenoxybenzamine, given intravenously.4. In producing fasciculation, the adrenaline appeared to be acting on or through the lateral aspect of the upper cervical cord, about the line of emergence of the roots of the spinal accessory nerve, mainly in C1 and C2.5. The electromyograms of the fasciculation due to adrenaline and 5-HT showed intermittent bursts of activity. After adrenaline, the bursts consisted of fewer spikes than after 5-HT. The intervals between consecutive spikes were 3.75-5 msec after either amine, and the bursts occurred irregularly, at frequencies between 7 and 12/sec.6. It is suggested that adrenaline and 5-HT have excitatory actions on the dendrites or somata of the spinal accessory motor neurones, and the possible role of these amines as synaptic transmitters in the spinal nucleus of the accessory nerve is discussed.