Spinocerebellar tract

The spinocerebellar tracts are afferent neurons that convey proprioceptive data from the spinal cord to the cerebellum. There are anterior (or Gowers' tract) and posterior spinocerebellar tracts, also eponymously named the latter also referred to asGowers tract and Flechsig's tract respectively. Both the anterior and posterior spinocerebellar tracts lie in the periphery of the lateral funiculus of the spinal cord's lateral funiculus.

These tracts play a critical role in cerebellar-cortical-spinal feedback loops necessary for balance and coordination.

Gross anatomy

Central connections

Anterior spinocerebellar fibres connect to the superior cerebellar peduncle. Posterior spinocerebellar fibres connect to the inferior cerebellar peduncle.

Course

Both tracts are supplied by Golgi tendon organs and cutaneous touch and pressure receptors peripherally. Relevant nerve fibres enter at the dorsal nerve roots.

Anterior spinocerebellar tract

Fibres destined for the anterior spinocerebellar tract synapse with posterior horn cells in lumbar and sacral segments. From here, fibres cross to the opposite side of the cord, forming the anterior spinocerebellar tract which then ascends to the midbrain along the ventral aspect of the lateral funiculus. It then descends back into the superior cerebellar peduncle. The fibres then cross to the contralateral side. Therefore, the anterior spinocerebellar tract crosses over twice and terminates ipsilateral to its origin.

Posterior spinocerebellar tract

Fibres for the posterior spinocerebellar tract (or Flechsig's tract) enter the spinal cord from the posterior root ganglion and synapse with cells in the thoracic nucleus, also known as the Clarke's column. This occurs at the posterior horn of all 12 thoracic and the first 2 lumbar segments. The posterior spinocerebellar tract then ascends up to the medulla along the dorsal lateral funiculus, adjacent to the lateral corticospinal tract. It finally connects to the cerebellum at the ipsilateral inferior cerebellar peduncle. Fibres in the posterior spinocerebellar tract terminate ipsilateral to their origin, and do not decussate at all and also terminates ipsilateral to its origin. 

History and etymology

The spinocerebellar tracts were named after the two scientists who studied them: Paul Emil Flechsig, German psychiatrist and William Richard Gowers, English neurologist.

Related pathology 

• Spinal cord injury
• Multiple sclerosis
• Brown-Séquard syndrome