A 50yo woman presents following a fall. She reports pain and weakness in her hands for several
months, stiff legs, swallowing difficulties, and has bilateral wasting of the small muscles of her
hands. Reflexes in the upper limbs are absent. Tongue fasciculations are present and both legs
show increased tone, pyramidal weakness and hyper-reflexia with extensor plantars. Pain and
temp sensation are impaired in the upper limbs. What is the most likely dx?
a. MS
b. MND
c. Syringobulbia
d. Syringomyelia
e. Myasthenia gravis
answer: C ,
Pain and temper sensation loss in upper limb, weakness, wasting, all characteristic of syringomyelia but since there is cranial nerve involvement (e.g. tongue wasting and fasciculations), this means it is a case of syringobulbia due to involvement of the medulla.
MS
Pseudo-bulbar e.g. No fasciulations
MND
• limb motor symptoms: segmental and asymmetrical UMN and LMN symptoms
• bulbar findings: dysarthria (flaccid or spastic), dysphagia, tongue atrophy and fasciculations, facial weakness and atrophy
• pseudobulbar affect, frontotemporal dementia (up to 10%)
• sparing of sensation, ocular muscles, and sphincters
Syringomyelia
nonspecific features for any intramedullary spinal cord pathology
initially pain, weakness, atrophy, loss of pain and temperature in upper extremities (central syrinx) with progressive myelopathy over years
sensory loss with preserved touch and proprioception in a band-like distribution at the level of cervical syrinx
dysesthetic pain often occurs in the distribution of the sensory loss
LMN arm/hand weakness or wasting
painless neuropathic arthropathies (Charcot’s joints), especially in the shoulder and neck due to loss of pain and temperature sensation
Syringobulbia
This occurs if the syrinx extends into the medulla of the brainstem. The cranial nerves become affected:
Facial sensory loss can occur as the trigeminal nerve becomes involved.
Vestibulocochlear nerve involvement causes vertigo and nystagmus.
Facial, palatal and laryngeal nerve palsy can occur as the VIIth, IXth, Xth and XIth cranial nerves become involved.
Weakness and atrophy of the tongue is caused by XIIth nerve involvement.
Myasthenia Gravis
• ocular (diplopia/ptosis), bulbar (dysarthria/dysphagia), and/or proximal limb weakness
• fatiguable, symmetric or asymmetric weakness without reflex changes, sensory changes, or
coordination abnormalities