What Is Bulbar Muscle Weakness
The causes of this are broadly divided into.
What is bulbar muscle weakness. Spinal and bulbar muscular atrophy sbma or kennedy s disease is an x linked motor neuron disease typically presenting in adult men in the 3rd to 5th decades. Muscles of the mouth and throat responsible for speech and swallowing. In contrast pseudobulbar palsy is a clinical syndrome similar to bulbar palsy but in which the damage is located in upper motor neurons of the corticobulbar tracts in the mid pons i e in the cranial nerves ix xii that is the nerve cells coming down from the cerebral cortex innervating the motor nuclei in the medulla. Bulbar palsy is the result of diseases affecting the lower cranial nerves vii xii.
A speech deficit occurs due to paralysis or weakness of the muscles of articulation which are supplied by these cranial nerves. About 15 of patients present with bulbar symptoms. The bulbar als or bulbar onset is seen in about 25 of patients who are to develop als. There are differences between bulbar palsy and pseudobulbar palsy.
Bulbar palsy vs pseudobulbar palsy. Spinal and bulbar muscular atrophy sbma popularly known as kennedy s disease is a progressive debilitating neurodegenerative disorder resulting in muscle cramps and progressive weakness due to degeneration of motor neurons in the brainstem and spinal cord. Bulbar als symptoms are seen in 75 to 80 of the patients with classic als symptoms. Gradually almost all the muscles under voluntary control are affected and individuals lose their strength and the ability to speak eat move and even breathe.
Bulbar weakness is often associated with difficulty in chewing weakness of the facial muscles. Weakness and fatigue in the neck and jaw also can occur early in mg. The condition is associated with mutation of the androgen receptor ar gene and is inherited in an x linked recessive manner. The classic presentation is of slow progression of proximal weakness bulbar weakness including asymmetric or symmetric facial weakness and gynecomastia.
Bulbar relates to the medulla. This bulbar weakness named for the nerves that originate from the bulblike part of the brainstem can cause difficulty with talking dysarthria chewing swallowing dysphagia and holding up the head. The former is a lower motor neuron lesion of the cranial nerves ix x xi and xii while the latter is an upper motor neuron lesion affecting ix x xi and xii cranial nerves. Early symptoms of als usually include muscle weakness or stiffness in a limb or muscles of the mouth or throat so called bulbar muscles.
This is because the motor neuron cells in the spinal cord degenerate leading to their death due to als.