How would damage to the left posterior column affect you?

Posterior column mediates a pathway called as posterior column medial lemniscus pathway in central nervous which is responsible for mediating certain sensations like touch, vibration etc. Damage to the left posterior column unable to transmit signals to the primary somatosensory cortex in the gyrus and parietal  lobe of the brain.

Explanation:

The spinal cord and cerebrum is connected by some specialized tract called as white matter tract. These tracts are either ascending or descending.The another name of ascending pathway is known as medial lemniscus pathway.The origin of this pathway takes place within posterior column of the spinal cord.Posterior column medial lemniscus pathway is important as it transmit signals to the cerebrum which is responsible for generating impulse like vibration, touch etc.Thus damage to this column can't be able to transmit signals to different parts of cerebrum and thus impulse like touch, vibration,pressure etc will not generate.