The lower ago houses the terminal finish of the spinal cord and mostly encloses the cauda equina—nerve roots that descend indigenous the spinal cord. The spinal cord and also the cauda equina room delicate and important structures. The spinal canal developed by the lumbar vertebrae protects these frameworks by providing a strong, bony casing.

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Video: Lumbar Spine Anatomy

Learn just how the lumbar spinal discs duty and exactly how lower earlier conditions can cause ago pain and/or radiating pain. Watch currently

Lumbar Spinal Cord

The spinal cord terminates in the lumbar spine. The exact point of discontinuation varies among individuals; many commonly, that terminates in ~ the level that the L1 or L2 vertebrae. A few anatomical structures related to the lumbar spinal cord space highlighted below.

Conus medullaris

The terminal section of the spinal cord in the lumbar region is cone-shaped and also is called the conus medullaris.

The conus medullaris is made up of number of neurons (nerve cells) and also has 3 protective layers. Starting from the outermost layer, these room the dura mater, arachnoid mater, and pia mater. The pia mater tapers and also continues down as the filum terminale at the finish of the conus medullaris.1


Filum terminale

The pia mater develops a delicate, fibrous strand the tissue called the filum terminale that extends under from the conus medullaris. This strand stabilizes the spinal cord by connecting the conus medullaris to the coccyx (end the the spine).1

Thecal sac

The dura mater and also arachnoid mater are collectively called the dural sac or the thecal sac. This sac consist of the conus medullaris, cauda equina, and also each individual spinal nerve root as it process out of the cauda equina and travels into the intervertebral foramen (bony opening with which the nerve exits the spinal canal).2

Lumbar cistern

The space inside the arachnoid mater is filled with cerebrospinal liquid (CSF). Listed below the conus medullaris, this an are is enlarged. This enlargement is dubbed the lumbar cistern and also contains CSF, the filum terminale, and also the cauda equina.2

The Cauda Equina

A team of nerve roots that travel down from the spinal cord and also the conus medullaris is referred to as the cauda equina. The cauda equina consists of nerve root from L2 in the lumbar spine come Co1 in the coccygeal (tail bone end) spine.1 every nerve root from the cauda equina exits the spinal canal at its particular vertebral level, for example, the L4 nerve source exits between the L4 and L5 vertebrae.

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Spinal Cord and Cauda Equina that the Lumbar Spine

Problems related to the Lumbar Spinal Cord and Cauda Equina

The terminal organization of the spinal cord in the lower back can acquire compressed, irritated, or abnormally stretched and typically reason serious clinical problems. Feasible conditions affect this region along with the specific symptoms, signs, and also causes are described below.

Cauda Equina Syndrome

The cauda equina is created by the continuation of nerve fibers beyond the spinal cord. Compression that the cauda equina, such together by a herniated disc, may cause severe pain and numbness in both legs. Read an ext about Cauda Equina Syndrome

Conus medullaris syndrome

Compression of the conus medullaris in the lumbar an ar at L1-L2 (typically between T12 come L2) causes conus medullaris syndrome. This syndrome is identified by the following signs and also symptoms1:

Sudden start of severe back painNumbness around the anal regionWeakness that occurs symmetrically in both legsSudden start of bowel and bladder dysfunctionThe most common causes of conus medullaris syndrome include spinal fracture, key herniation, tumors, trauma, and collection the pus in the epidural space due to infection (epidural abscess).1

Conus medullaris syndrome is a medical emergency and also requires instant treatment to maintain leg function.

Tethered cord syndrome

An abnormal filum terminale can change the stability of the conus medullaris and prevent that is normal activity in the spinal canal. This condition is called tethered cord syndrome and also causes the spinal cord to acquire abnormally stretched, especially throughout actions such as spinal flexion (bending forward).1 usual signs and symptoms include3:

Urinary dysfunction: boosted urination or retention that urineUrinary street infectionsBack pain, i m sorry is enhanced while bending the spine forward and also relieved while bending the neck backwardConstipation

While this problem is generally identified throughout periods the rapid development in adolescence, the symptoms may not happen until adulthood. Common reasons of tethered cord syndrome are break-up spinal cord (diastematomyelia), spinal cord lining difficulties (dermal sinuses), and also lumps that fatty organization in the spinal cord an ar (lipomas).1

Cauda Equina Syndrome Video

Cauda equina syndrome

Compression that the cauda equina within the lumbar cistern can cause serious symptom in the reduced body. The problem is called cauda equina syndrome and also presents through the complying with signs and also symptoms4:

Numbness that the within thighs (saddle anesthesia)Urinary retentionLoss the bowel and/or bladder controlSevere lower ago painSciatica-like shooting and also burning pain in the leg(s)A feeling of pins-and-needles in the leg(s)

Cauda equina syndrome can existing in 2 ways: acute onset, wherein the symptoms and also signs take place rapidly, and also insidious onset, wherein the condition starts as lower ago pain and also slowly progresses come bowel and urinary incontinence.4

Read an ext about Cauda Equina Syndrome symptoms


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Cauda equina syndrome is most generally caused through compression indigenous a lumbar herniated disc. Compression may additionally occur as result of tumors, cysts, stenosis (abnormal narrowing of the spinal canal), or trauma. Cauda equina syndrome is a medical emergency. Instant treatment is an important for the prevention of paralysis and preservation of foot function.4

Read more about causes of Cauda Equina Syndrome

If any kind of of these spinal cord related difficulties are suspected, it is recipient to consult a doctor immediately. Spinal cord disorders might be treated nonsurgically or surgically depending on the cause and also the all at once health that the patient. The prognosis increases significantly when cure early.

See When earlier Pain might Be a medical Emergency