CorpusHuman Anatomy
NervousNeural pathway

Spinocerebellar tracts

Also known as: dorsal spinocerebellar tract, ventral spinocerebellar tract, posterior spinocerebellar tract, anterior spinocerebellar tract, cuneocerebellar tract

Ascending pathways that carry unconscious proprioception from muscle spindles, Golgi tendon organs and spinal interneurons to the cerebellum. Each one ultimately reaches the cerebellar hemisphere on the same side as its origin.

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Overview

These two-neuron pathways inform the cerebellum about limb position, muscle length and tension, and the activity of spinal motor circuits. The cerebellum uses this to coordinate movement and posture. The information does not reach consciousness. All of them end as mossy fibres in the ipsilateral cerebellar cortex. This is why cerebellar lesions produce ipsilateral signs.

• Dorsal (posterior) spinocerebellar tract: carries lower limb and lower trunk input. Proprioceptive afferents synapse in Clarke's nucleus (C8–L3). Afferents from below L3 first ascend in the fasciculus gracilis to reach it. The second-order axons ascend uncrossed in the superficial lateral funiculus and enter the cerebellum via the inferior cerebellar peduncle.
• Cuneocerebellar tract: the upper-limb equivalent. Fibres relay in the accessory (lateral) cuneate nucleus of the medulla and enter via the inferior cerebellar peduncle.
• Ventral (anterior) spinocerebellar tract: lower limb. Second-order neurons in laminae V–VII receive input about spinal interneuron activity (an internal copy of motor commands). Their axons cross in the anterior white commissure, ascend to the upper pons and enter via the superior cerebellar peduncle, where they cross back. The double crossing ends ipsilateral.
• Rostral spinocerebellar tract: the upper-limb equivalent of the ventral tract. It is uncrossed.

Parts & subdivisions

  1. Dorsal spinocerebellar tract
    Origin Clarke's nucleus (C8–L3). Ipsilateral throughout. Enters via the inferior cerebellar peduncle. Carries lower-limb proprioception.
  2. Ventral spinocerebellar tract
    Origin laminae V–VII of the lumbosacral cord. Crosses twice, in the cord and in the superior cerebellar peduncle. Carries internal feedback on spinal motor circuits.
  3. Cuneocerebellar tract
    Upper-limb proprioception via the accessory cuneate nucleus. Enters via the inferior cerebellar peduncle.

Anatomy

Course

Muscle spindles and Golgi tendon organs → DRG → Clarke's nucleus (dorsal tract) or accessory cuneate nucleus (cuneocerebellar), or laminae V–VII (ventral tract) → lateral funiculus → inferior or superior cerebellar peduncle → ipsilateral cerebellar cortex (spinocerebellum: vermis and paravermis).

Function

  • Supplies the cerebellum with continuous unconscious proprioceptive feedback for coordination and muscle tone.
  • Provides the cerebellum with an efference copy of spinal motor activity, through the ventral tract, so it can correct movements.

Clinical significance

Friedreich ataxia

An autosomal recessive GAA trinucleotide expansion in FXN (frataxin), on chromosome 9. It causes degeneration of the spinocerebellar tracts, dorsal columns, corticospinal tracts and DRG. Onset is in adolescence, with progressive gait and limb ataxia, areflexia with extensor plantars, loss of vibration sense, dysarthria, pes cavus and kyphoscoliosis. Hypertrophic cardiomyopathy is the usual cause of death, and diabetes is common.

Compiled from standard anatomy and physiology references — see the Nervous System sources. For education only; not medical advice.