Large motor units are selectively affected following a stroke.
Clin Neurophysiol
; 119(11): 2555-8, 2008 Nov.
Article
en En
| MEDLINE
| ID: mdl-18809353
ABSTRACT
OBJECTIVE:
Previous studies have revealed a loss of functioning motor units in stroke patients. However, it remained unclear whether the motor units are affected randomly or in some specific pattern. We assessed whether there is a selective loss of the large (high recruitment threshold) or the small (low recruitment threshold) motor units following a stroke.METHODS:
Forty-five stroke patients and 40 healthy controls participated in the study. Macro-EMG was recorded from the abductor digiti minimi muscle at two levels of force output (low and high). The median macro motor unit potential (macro-MUP) amplitude on the paretic side was compared with those on the unaffected side and in the controls.RESULTS:
In the control group and on the unaffected side, the macro-MUPs were significantly larger at the high force output than at the low one. However, on the paretic side the macro-MUPs at the high force output had the same amplitude as those recorded at the low force output. These changes correlated with the severity of the paresis.CONCLUSIONS:
Following a stroke, there is a selective functional loss of the large, high-threshold motor units. These changes are related to the severity of the symptoms.SIGNIFICANCE:
Our findings furnish further insight into the pathophysiology of the motor deficit following a stroke.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Potenciales de Acción
/
Músculo Esquelético
/
Accidente Cerebrovascular
/
Neuronas Motoras
Tipo de estudio:
Observational_studies
Límite:
Adult
/
Aged
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Clin Neurophysiol
Asunto de la revista:
NEUROLOGIA
/
PSICOFISIOLOGIA
Año:
2008
Tipo del documento:
Article
País de afiliación:
Hungria