[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Spine](https://durgical.com/en/anatomy/region/spine/) › Spinal cord [Nervous system](https://durgical.com/en/anatomy/system/nervous-system/) · [Spine](https://durgical.com/en/anatomy/region/spine/) # Spinal cord The spinal cord is the main nerve cable joining the brain to the body; it runs inside the spinal canal from the skull to about [L1-L2](https://durgical.com/en/anatomy/l1-l2/). [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=spine&select=spinal_cord&side=r) Opens in the Durgical app, no sign-up needed. ## What it is The main nerve cable joining the brain to the body, running inside the spinal canal from the skull to about the L1-L2 level. ## What it does Carries movement signals from the brain and sensation back to it, and handles reflexes on its own. ## Key points - Cord segments lie higher than the vertebrae of the same number: about one level in the neck, two in the upper thoracic [spine](https://durgical.com/en/anatomy/region/spine/), and the lumbar, sacral and coccygeal segments sit behind T10–L1 - Dorsal columns (vibration, position) and the lateral corticospinal tract cross in the medulla, so a cord lesion affects them on the same side; the spinothalamic tract (pain, temperature) crosses at entry: opposite side - Blood supply: one anterior spinal artery for about the front two-thirds, two [posterior spinal arteries](https://durgical.com/en/anatomy/posterior-spinal-arteries/) for the dorsal columns; the [artery of Adamkiewicz](https://durgical.com/en/anatomy/great-radicular-artery/) (usually left, T9–T12) feeds the lower cord - Cord damage gives lower motor neuron signs at the level and upper motor neuron signs below it; right after an injury, spinal shock first leaves the limbs flaccid and areflexic ## Key facts **Where** Vertebral canal from foramen magnum (continuous with medulla) to about L1–L2 in adults; about 42–45 cm long; cervical (C4–T1) and lumbosacral (L1–S3) enlargements **Attaches** Denticulate ligaments (pia to dura) on each side; [filum terminale](https://durgical.com/en/anatomy/filum-terminale-internum/) to [coccyx](https://durgical.com/en/anatomy/coccyx/) **Function** Ascending sensory and descending motor tracts; 31 pairs of spinal nerves; spinal reflexes; lateral horn: sympathetic preganglionic neurons T1–L2 (ciliospinal centre C8–T2), sacral parasympathetic S2–S4 ## Relations **Course** From the [foramen magnum](https://durgical.com/en/anatomy/foramen-magnum/), where it continues from the [medulla oblongata](https://durgical.com/en/anatomy/medulla-oblongata/), down the vertebral canal to the [conus medullaris](https://durgical.com/en/anatomy/conus-medullaris/) at about L1–L2; the lower its roots arise, the longer and steeper their path down to their foramina, ending as the [cauda equina](https://durgical.com/en/anatomy/cauda-equina/) **In front** Across the epidural space, the [posterior longitudinal ligament](https://durgical.com/en/anatomy/posterior-longitudinal-ligament/) over the vertebral bodies and discs; the [anterior spinal artery](https://durgical.com/en/anatomy/anterior-spinal-artery/) runs in the anterior median fissure **Behind** Epidural fat and veins, then the laminae and [ligamenta flava](https://durgical.com/en/anatomy/ligamenta-flava/) **Lateral** Denticulate ligaments to the dura, between the anterior and posterior roots, and the roots heading to the intervertebral foramina **Superficial** From inside out: pia mater, the subarachnoid space with CSF, arachnoid and [dura mater](https://durgical.com/en/anatomy/cranial-dura/), then the epidural space with the internal vertebral venous plexus **Contents** [White matter](https://durgical.com/en/anatomy/white-matter-of-telencephalon/) in three funiculi around the grey H: posterior (fasciculus [gracilis](https://durgical.com/en/anatomy/gracilis-muscle/) medially for the leg, cuneatus laterally for the arm, above T6), lateral (lateral corticospinal, dorsal and ventral spinocerebellar, rubrospinal; spinothalamic fibres anterolaterally) and anterior (anterior corticospinal, vestibulo-, tecto- and reticulospinal) ## How to find it It cannot be felt. Its levels are estimated from surface landmarks: [vertebra prominens](https://durgical.com/en/anatomy/vertebra-prominens/) (C7), inferior angle of the [scapula](https://durgical.com/en/anatomy/scapula/) (about T7) and the line across the iliac crests (about L4, Tuffier line), well below the end of the cord. Segment under a spinous process: add about 1 in the neck, 2 at T1–T6, 3 at T7–T9; T10–T12 spines overlie the lumbar segments, L1 the sacral ones. ## Examination - ISNCSCI (ASIA) examination: 10 key muscles and 28 key sensory points per side plus an anal exam; the neurological level is the lowest segment with normal strength and sensation on both sides - Babinski sign: stroking the outer sole makes the [big toe](https://durgical.com/en/anatomy/great-toe/) extend and the other toes fan; an upper motor neuron sign (normal in infants) - Hoffmann sign: flicking the nail of the middle finger makes the thumb and index flex; it suggests an upper motor neuron lesion, often cervical myelopathy - Lhermitte sign: bending the neck forward sends an electric feeling down the spine or limbs; it points to a cervical dorsal column lesion (multiple sclerosis, myelopathy) - Romberg test: steady with eyes open, swaying or falling with eyes closed; loss of position sense, as in dorsal column disease - Reflexes map the segment: biceps C5–C6, [brachioradialis](https://durgical.com/en/anatomy/brachioradialis/) C6, triceps C7, patellar L3–L4, Achilles S1; superficial abdominal T8–T12, cremasteric L1–L2, anal wink and bulbocavernosus S2–S4; a lost reflex marks the level, brisk reflexes lie below it ## On imaging MRI is the study of choice: T2 shows compression by disc, bone or ligament and bright signal inside the cord (oedema, myelomalacia, syrinx). CT shows fractures and the bony canal better; CT myelography is used when MRI is not possible. ## Common problems - Cervical myelopathy: slow squeezing by discs, spurs or a thick ligament, causing clumsy hands, numbness and unsteady walking. - Spinal cord injury from fractures or dislocations, which can cause paralysis below the level. - Inflammation (myelitis), tumours or problems with its blood supply. ## How it is diagnosed Neurological exam (strength, feeling, reflexes, balance) and MRI. ## Treatment - Cord compression with symptoms: surgery to take pressure off, such as ACDF in the neck. - Acute injury: emergency care to stabilise the spine, then rehabilitation. ## Clinical notes - Complete vs incomplete injury: in a complete injury (ASIA A) no motor or sensory function remains in S4–S5; any sacral sparing (perianal feeling, voluntary anal squeeze) makes it incomplete, with a better outlook - Central cord syndrome, the commonest incomplete pattern: an older person with a narrowed, stiff cervical spine falls and hyperextends the neck; arms weaker than legs, hands worst, variable sensory and bladder loss - Brown-Séquard syndrome (hemisection, e.g. a stab wound): same-side weakness and loss of vibration and position sense, opposite-side loss of pain and temperature starting one or two segments below the lesion; anterior cord syndrome (anterior spinal artery): paralysis and pain loss with dorsal columns spared - Cervical spondylotic myelopathy, the commonest cord disorder in older adults: the clumsy hand, broad-based gait, Hoffmann sign and brisk reflexes build up slowly, often with little neck pain - Conus vs cauda equina: a conus lesion starts suddenly and symmetrically, with early sphincter failure, little pain and mixed upper and lower motor neuron signs; cauda equina compression is often asymmetric, painful and purely lower motor neuron ## Development In the third fetal month the cord fills the whole canal; the column then outgrows it, so the conus lies at about L3 at birth and reaches the adult level in infancy. A tight filum that holds it low (tethered cord) stretches the cord as the child grows. ## Related conditions - [Morquio syndrome (mucopolysaccharidosis type IV)](https://durgical.com/en/conditions/morquio-syndrome/) - [Multiple sclerosis](https://durgical.com/en/conditions/multiple-sclerosis/) - [Spinal cord injury](https://durgical.com/en/conditions/spinal-cord-injury/) - [Degenerative cervical myelopathy](https://durgical.com/en/conditions/degenerative-cervical-myelopathy/) - [Spinal epidural abscess](https://durgical.com/en/conditions/spinal-epidural-abscess/) - [Spina bifida (myelomeningocele)](https://durgical.com/en/conditions/spina-bifida/) - [Neurogenic shock](https://durgical.com/en/conditions/neurogenic-shock/) - [Decompression sickness and diving injuries](https://durgical.com/en/conditions/decompression-sickness-and-diving-injuries/) - [Malignant spinal cord compression](https://durgical.com/en/conditions/malignant-spinal-cord-compression/) - [Tetanus](https://durgical.com/en/conditions/tetanus/) - [Poliomyelitis and acute flaccid paralysis](https://durgical.com/en/conditions/poliomyelitis-and-acute-flaccid-paralysis/) - [Amyotrophic lateral sclerosis](https://durgical.com/en/conditions/amyotrophic-lateral-sclerosis/) - [Subacute combined degeneration (vitamin B12)](https://durgical.com/en/conditions/subacute-combined-degeneration/) - [Autonomic dysreflexia](https://durgical.com/en/conditions/autonomic-dysreflexia/) - [Spinal muscular atrophy](https://durgical.com/en/conditions/spinal-muscular-atrophy/) - [Transverse myelitis](https://durgical.com/en/conditions/transverse-myelitis/) - [Neuromyelitis optica spectrum disorder](https://durgical.com/en/conditions/neuromyelitis-optica-spectrum-disorder/) - [Syringomyelia and Chiari malformation](https://durgical.com/en/conditions/syringomyelia-and-chiari-malformation/) - [Friedreich ataxia](https://durgical.com/en/conditions/friedreich-ataxia/) - [HTLV-1-associated myelopathy / tropical spastic paraparesis](https://durgical.com/en/conditions/htlv-1-associated-myelopathy-tropical-spastic-paraparesis/) - [Major trauma (polytrauma): ATLS primary survey](https://durgical.com/en/conditions/major-trauma-atls-primary-survey/) - [Cervical spine fracture](https://durgical.com/en/conditions/cervical-spine-fracture/) - [Cervical Spondylosis](https://durgical.com/en/conditions/cervical-spondylosis/) ## Test yourself Think of the answer, then tap the question to see it. ## At what vertebral level does the adult spinal cord end? At about L1–L2, as the conus medullaris; it is continuous with the medulla at the foramen magnum. ## Which artery feeds the lower spinal cord, and where does it usually arise? The artery of Adamkiewicz, usually on the left between T9 and T12; the anterior spinal artery supplies about the front two-thirds of the cord. ## What is the pattern of Brown-Séquard syndrome? Cord hemisection: same-side weakness and loss of vibration and position sense; opposite-side loss of pain and temperature. ## Which incomplete spinal cord injury is most common, and what is its typical picture? Central cord syndrome: an older person with a stiff, narrow cervical spine hyperextends the neck; arms weaker than legs, hands worst. ## What makes a spinal cord injury incomplete on the ASIA scale? Any sacral sparing (perianal sensation or voluntary anal squeeze in S4–S5); a complete injury (ASIA A) has none, and incomplete ones have a better outlook. [Add to my cards (5)](https://durgical.app/estudiar/?add=/en/anatomy/spinal-cord/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** medulla spinalis; substantia alba medullae spinalis TA2 6049 **Official Spanish (DeCS)** Médula espinal DeCS D013116 **English (TA2)** Spinal cord **Also called** white columns of spinal cord ## Related - [Dura (dural sac)](https://durgical.com/en/anatomy/spinal-dura/) - [Conus medullaris](https://durgical.com/en/anatomy/conus-medullaris/) - [Grey matter of the cord](https://durgical.com/en/anatomy/grey-matter-of-spinal-cord/) - [Vertebral artery](https://durgical.com/en/anatomy/vertebral-artery/) - [Posterior intercostal arteries](https://durgical.com/en/anatomy/posterior-intercostal-arteries/) - [Anterior spinal artery](https://durgical.com/en/anatomy/anterior-spinal-artery/) - [Posterior spinal arteries](https://durgical.com/en/anatomy/posterior-spinal-arteries/) - [Artery of Adamkiewicz](https://durgical.com/en/anatomy/great-radicular-artery/) Sources: Terminologia Anatomica (TA2); [DeCS](https://decs.bvsalud.org/es/ths/resource/?id=13499); [Neuroanatomy, Spinal Cord](https://www.ncbi.nlm.nih.gov/books/NBK559056/); [Neuroanatomy, Spinal Cord Morphology](https://www.ncbi.nlm.nih.gov/books/NBK545206/); Tratado de anatomía humana (9.ª ed.), tomo II, Sistema nervioso central: cerebro, núcleos grises centrales, vías de conducción y circulación cerebral; Tratado de anatomía humana (9.ª ed.), tomo II, Libro V Sistema nervioso central, sección 1: Médula espinal. ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/spinal-cord/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/spinal-cord/