Musculus sacrocaudalis ventralis medialis
The sacrocaudalis muscles are the primary muscles controlling the equine tail. The sacrocaudalis dorsalis lateralis elevates and laterally deviates the tail. The sacrocaudalis dorsalis medialis elevates the tail dorsally (lifts it straight up). The sacrocaudalis ventralis lateralis depresses the tail and assists in lateral movement. The sacrocaudalis ventralis medialis depresses the tail ventrally (pulls it down). They originate from the sacral and caudal vertebrae and insert on the corresponding caudal vertebrae. All are innervated by the caudal (coccygeal) spinal nerves.
Origin: Ventral surfaces of sacral and caudal vertebrae
Insertion: Ventral caudal vertebrae
Action: Depresses the tail ventrally
Innervation: Caudal (coccygeal) spinal nerves
Isolated injury is uncommon. Tail tone and movement are assessed in neurologic examinations. Trauma to the tail or sacrocaudal region can affect these muscles and associated nerves. Relevant in evaluations of cauda equina or sacral nerve dysfunction.
## Overview Asymmetric tail carriage or inability to move the tail normally can indicate unilateral nerve damage, sacral fracture, nerve-root compression, or localized muscle injury. Deviation to one
Persistent abnormal tail carriage, weakness, or asymmetry after trauma should be evaluated. Protect the tail from injury during transport and handling.
## Overview Asymmetric tail carriage or inability to move the tail normally can indicate unilateral nerve damage, sacral fracture, nerve-root compression, or localized muscle injury. Deviation to one side at rest or asymmetric swishing warrants neurologic evaluation. ## Causes Nerve damage, fracture, or muscle injury. ## Diagnosis Neurologic examination of tail tone and movement, plus imaging if trauma is suspected. ## Treatment Directed at the underlying cause. ## Recovery and Prognosis Depends on the lesion. Mild muscle injuries improve. Nerve damage may be permanent. ## Prevention Trauma avoidance. Signs include: tail deviates to one side at rest; asymmetric tail swishing; may indicate sacral fracture, nerve-root compression, or muscle damage
Isolated injury is uncommon. Tail tone and movement are assessed in neurologic examinations. Trauma to the tail or sacrocaudal region can affect these muscles and associated nerves. Relevant in evaluations of cauda equina or sacral nerve dysfunction.
Persistent abnormal tail carriage, weakness, or asymmetry after trauma should be evaluated. Protect the tail from injury during transport and handling.
See the Sacrocaudalis Ventralis Medialis on our interactive 3D horse model. Open 3D Model