Posterior spinocerebellar tract

The posterior spinocerebellar tract is an example of an ascending sensory tract. It serves to transmit unconscious proprioceptive information from the muscle spindles, golgi tendon organs and joint receptors, to the cerebellum. The information about the movements of the muscles and joints and the associated tension in the tendons is computed by the cerebellum to coordinate muscle movements and maintain posture and gait.

The axons of first order neurons arise from the dorsal root ganglion and enter the posterior gray horn of spinal cord via the posterior nerve rootlets. These synapse with the cell bodies of the second order sensory neurons in the nucleus dorsalis (or Clarke’s column). The nucleus is situated in the lateral intermediate substance in the base of posterior horn (lamina VII). It is to be noted that the nucleus dorsalis resides in the C8-L3 spinal segments only, and hence axons entering spinal cord via upper cervical or lower lumbar and sacral spinal nerves must descend or ascend a few segments before they are able to synapse with the nucleus dorsalis.

The second order sensory axons from the nucleus dorsalis, ascend in the posterolateral part of the lateral funiculus (or lateral white column), on the same side, as the posterior spinocerebellar tract. The tract reaches the medulla oblongata, where it passes through the inferior cerebellar peduncle to terminate in the cerebellar cortex.

A lesion in lateral spinal cord that effects the spinocerebellar tracts, can lead to problems with muscle coordination. The motor deficits could manifest as nystagmus, dysmetria, dysdiadochokinesia and gait imbalance, all on the same side of the lesion.