Neurological examination Flashcards
What is a Brown-Sequard lesion?
How does it present?
Incomplete spinal cord lesion characterized by a clinical picture reflecting hemisection injury of the spinal cord, often in the cervical cord region.
Patients with Brown-Séquard syndrome suffer from ipsilateral upper motor neuron paralysis and loss of proprioception, as well as contralateral loss of pain and temperature sensation. A zone of partial preservation or segmental ipsilateral lower motor neuron weakness and analgesia may be noted. Loss of ipsilateral autonomic function can result in Horner syndrome.
What is a sensory level? Lesions of what structure is this important for?
sensory level is defined as the most caudal dermatome with normal sensation
Spinal cord lesions
What are fasciculations? Are they an UMN sign or LMN sign?
LMN sign
Irregular contractions of small areas of muscles with no rythmic pattern.
Fasciculations arise as a result of spontaneous depolarization of a lower motor neuron
What us the difference between spasticity and rigidity?
Spasticity= increased tone depending on position and speed of movement. eg ‘clasp knife’ motion.
Rigidity= increased tone no matter where you are in the movement. ‘ lead pipe’. Indicates ‘extra-pyramidal’ pathway–> ‘cogwheel’ rigidity (cogwheeling is due to tremor)
How can you increase cogwheel rigidity in Parkinson’s disease?
circle the opposite arm
What is spasticity caused by?
UMN lesion of corticospinal pathways
What are the 3 different types of tremor?
Coarse, resting tremor- Parkinson’s disease (usually assymetric, made worse when the patient is distracted)
Fine tremor- essential tremor (bilateral, wose when the patient is asked to perform a task eg writing)
Intention tremor- most pronounced during voluntary movement towards a target
What could a positive Romberg’s test mean?
Likely to indicate a cerebellar lesion or reduced LL sensation/ proprioception- peripheral neuropathy
What is the classical 4 characteristics of Parkinsonism?
rigidity, tremor, bradykinesia, postural instability
What is loss of smell an early sign of?
Parkinson’s disease
What is Rinne’s test?
The Rinne test is performed by placing a low frequency (512 Hz) vibrating tuning fork against the patient’s mastoid bone and asking the patient to tell you when the sound is no longer heard. Once they signal they can’t hear it, quickly position the still vibrating tuning fork 1–2 cm from the auditory canal, and again ask the patient to tell you if they are able to hear the tuning fork.
Normal Hearing: Air conduction should be greater than bone conduction and so the patient should be able to hear the tuning fork next to the pinna (outer ear) after they can no longer hear it when held against the mastoid.
Abnormal Hearing:
If they are not able to hear the tuning fork after the mastoid test, it means that their bone conduction is greater than their air conduction. This indicates there is something inhibiting the passage of sound waves from the ear canal, through the middle ear apparatus and into the cochlea (i.e., there is a conductive hearing loss).
What is Weber’s test?
top of the head equi-distant from the patient’s ears on top of thin skin in contact with the bone. The patient is asked to report in which ear the sound is heard louder. A normal weber test has a patient reporting the sound heard equally in both sides. In an affected patient, if the defective ear hears the Weber tuning fork louder, the finding indicates a conductive hearing loss in the defective ear. In an affected patient, if the normal ear hears the tuning fork sound better, there is sensorineural hearing loss on the other (defective) ear.
What 3 characteristics of tremor can be used to characterise it?
Distribution
Rate
Amplitude
Describe the features of a Parkinsonian gait
Flexed posture Reduced arm swing Enhanced resting tremor Shiffling/ festinating En bloc turning
