Musculus multifidus dorsi
The multifidus is a deep segmental muscle that spans 2–4 vertebral segments. It originates from the articular and transverse processes of vertebrae and inserts on the spinous processes of vertebrae 2–4 segments cranially. Its actions include fine segmental stabilization of the spine, proprioceptive feedback, and extension of individual segments. The cervical portion (multifidus cervicis) performs the same function in the neck. It is innervated by the medial branches of the dorsal rami of the spinal nerves (segmental). Research has shown that multifidus atrophy is closely correlated with back pain and osseous spinal pathology. The atrophy can be ipsilateral to the site of pathology and can persist after the original pain resolves. Targeted rehabilitation (dynamic mobilization exercises, belly lifts, and other core work) can increase multifidus cross-sectional area. Ultrasound is used to assess size and symmetry.
Origin: Articular and transverse processes of lumbar, thoracic, and cervical vertebrae
Insertion: Spinous processes 2-4 segments cranially
Action: Stabilizes individual vertebral segments; provides proprioceptive feedback for posture
Innervation: Medial branches of dorsal rami of spinal nerves (segmental)
Multifidus atrophy and asymmetry are common findings in horses with back pain, kissing spines, or chronic lameness. Ultrasound can measure cross-sectional area and compare left and right sides. Rehabilitation focused on core stabilization is often recommended.
## Overview The multifidus muscles stabilize individual vertebral segments. Back pain causes rapid, segmental atrophy of these muscles that can persist even after the pain resolves, creating a cycle
## Overview Post-surgical weakness refers to reduced core stability after back surgery, particularly for kissing spines. Even when the surgery is successful, the deep stabilizing muscles (multifidus)
Reluctance to bend, hollow back, or poor engagement under saddle can involve the multifidus and other deep stabilizers. Have persistent back issues evaluated. Core exercises can help restore function.
## Overview The multifidus muscles stabilize individual vertebral segments. Back pain causes rapid, segmental atrophy of these muscles that can persist even after the pain resolves, creating a cycle of instability and re-injury. Visible asymmetry or poor topline that does not respond to general exercise may be noted. ## What It Indicates Chronic or recent back pain leading to disuse of the deep spinal stabilizers. ## Diagnosis Ultrasound measurement of multifidus cross-sectional area, often asymmetric next to specific spinous processes. ## Treatment Targeted rehabilitation exercises that activate the multifidus, along with treatment of the original pain source. ## Recovery and Prognosis Muscle can be rebuilt with specific exercises, but recovery is slower than with general conditioning. ## Prevention Early treatment of back pain and inclusion of core-stability work. Signs include: visible or ultrasound-detected atrophy alongside specific spinous processes; poor topline unresponsive to general exercise; chronic back pain
## Overview Post-surgical weakness refers to reduced core stability after back surgery, particularly for kissing spines. Even when the surgery is successful, the deep stabilizing muscles (multifidus) are often atrophied and need targeted rehabilitation. Return to work is slower without specific core-strengthening exercises. ## Causes Pre-existing muscle atrophy plus surgical recovery. ## Diagnosis Clinical assessment of topline and movement after surgery. ## Treatment Structured rehabilitation emphasizing multifidus activation, gradual increase in work, and monitoring for residual pain. ## Recovery and Prognosis Improved with specific exercises. Horses that skip rehabilitation have higher rates of ongoing sensitivity. ## Prevention Inclusion of core work in the post-operative plan. Signs include: slow return to work after back surgery; ongoing sensitivity; improved with core-strengthening exercises
Multifidus atrophy and asymmetry are common findings in horses with back pain, kissing spines, or chronic lameness. Ultrasound can measure cross-sectional area and compare left and right sides. Rehabilitation focused on core stabilization is often recommended.
Reluctance to bend, hollow back, or poor engagement under saddle can involve the multifidus and other deep stabilizers. Have persistent back issues evaluated. Core exercises can help restore function.
See the Multifidus Dorsi on our interactive 3D horse model. Open 3D Model