A 47-year-old man complained to his physician that he had recently begun to experience some difficulty in maintaining his balance while attempting to walk and loss of ability to recognize objects placed in his hand when his eyes were closed. His internist referred him to a local neurology clinic where a battery of tests revealed the presence of a growing tumor. The tumor was most likely affecting the:
- Anterior spinocerebellar tract
- Posterior spinocerebellar tract
- Dorsolateral tract of Lissauer
- Dorsal columns
- Neospinothalamic tract
The dorsal columns of the spinal cord contain the fasciculus gracilis and fasciculus cuneatus. Patients with lesions in the dorsal columns have loss of kinesthetic sensation and, thus, are unable to identify the position of their limbs in space when their eyes are closed, and these patients also do not know if one of their joints is in flexion or extension. In addition, they cannot identify the shape, size, or texture of objects in their hands by means of touch (astereognosis). These patients are unable to perceive vibration when it is applied to their bodies and, therefore, cannot maintain steady posture when their eyes are closed. The posterior and anterior spinocerebellar tracts are involved in nonconscious sensation of limb proprioception. The lateral neospinothalamic tract and dorsolateral tract of Lissauer are involved in mediating pain sensation.
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