Neurological examination quiz Part 2

The nerve roots involved in the triceps reflex are C 7-8 (link)

The nerve roots involved in the finger reflex are C8. (link)

The nerve roots involved in the knee reflex are L 3-4. (link)

The nerve roots involved in the ankle reflex are L5 – S1. (link)

The nerve root involved in the plantar reflex is S1.

The cranial nerve involved in the jaw reflex is V (Trigeminal). (link)

Typical features of an upper motor neurone lesion include wasting which is usually  absent if acute and only mild when chronic. Tone is increased if chronic and decreased if acute. The weakness is usually greater in extensor and abductor muscles of the upper limb and greater in the flexors of the lower limb. (link)

Lower motor neurone lesions typically have wasting that is often profound when chronic, fasciculations, decreased tone and reflexes that are decreased or absent. (link)

Generalised symmetrical distal weakness is most likely due to a peripheral neuropathy. The weakness is usually mild. (link)

A generalised symmetrical proximal weakness is most likely due to a myopathy. (link)

Ipsilateral cranial nerve lesions and contralateral motor or sensory deficits are most likely due to a unilateral brainstem lesion. (link)

Weakness associated with visual field disturbance is most likely due to a cortical lesion. (link)

Pain and temperature sensation is transmitted via the spinothalamic pathway with the nerve fibres entering the spinal cord and crossing a few segments higher. It is less sensitive than 2 point discrimination in determining sensory loss in sensitive areas of the body (e.g. palm). The vibration and some proprioception pass through the nucleus gracilis and cuneatus in the medulla after ascending in the posterior columns of the spinal cord. (link)

A 256hz tuning fork is used to test hearing and bone conduction and is the same pitch as ‘middle C’ on a piano. (link)

Vibration testing in a limb should be performed from distal to proximal – if there is no distal loss, then proximal loss is highly unlikely and testing for it can usually be omitted.
The start of sensory loss at the same level around a limb suggests peripheral neuropathy.
When testing joint position sense, the joint should be flexed or extended at least 30 degrees – 10 degrees of movement is insufficient to test normal joint position sense. Light touch sensation is transmitted in the ipsilateral posterior columns and contralateral spinothalamic tracts. (link)