Vibration Sense

Use a tuning fork that vibrates at 128 per second. A normal adult can feel a vigorously vibrating tuning fork for 12-15 s at the ankle and for 15-20 s on the distal phalanx of the index finger. Instruct the patient as you place the handle of the vibrating fork on his sternum or jaw. Tell him you want to know when the vibration stops. Demonstrate this by grasping the vibrating tines of the fork with your other hand while the handle is firmly against his sternum. This will stop the vibration....

Biceps Reflex

Biceps Reflex

Musculocutaneous Nerve Sixth Cervical Root, Biceps and Brachialis Muscles The patient should be supine with his arms at his sides and his elbows flexed to 30-45 degrees. His arms are supine. Stand on the right side of the examining table to examine the right biceps reflex. Put your left index and middle fingers on the biceps tendon as shown in Figure 13-2A. Push your lingers into the antecubital fossa and partially supinate your hand, stretching the skin in the antecubital fossa. This lengthens...

Cochlear Nerve

Lesions of this special sensory nerve cause deafness. Nerve cells are in the spiral ganglion of the cochlea. Their peripheral connections are to the auditory cells of the organ of Corti, and their central connections are to the cochlear nucleus. The next-order neuron is the lateral lemniscus. When impulses concerned with sound have reached the cochlear nucleus, their further passage is bilateral (ie, a unilateral lesion above the level of the nucleus cannot cause deafness). Deafness Does the...

Some Diseases Of The Visual System Retina and Optic Nerve Lesions

Retrobulbar Neuritis Retrobulbar neuritis typically presents in young adults, with onset over 24-48 hr, a large central scotoma, and a painful eye on palpation and movement. There may be a past history of episodes of multiple sclerosis or this illness may be the first manifestation of it. The fundus is usually normal. Afferent pupillary defect is commonly present. Optic Neuritis The presentation of optic neuritis is like that of retrobulbar neuritis, except that it may be painless. The terms...