What is Tarlov Cyst

Name: What is Tarlov Cyst
Creator: DiseaseMaps Editorial Team
Published: 2015-06-11UTC09:46:17.0000000

What is Tarlov Cyst? Plain-language, medically reviewed definition plus the lived reality told by patients.

A Tarlov cyst is a fluid-filled, sac-like lesion that develops on the nerve roots of the spine, most commonly in the sacral (tailbone) region, and can cause significant neurological symptoms by compressing surrounding nerve tissue.

Understanding the Condition

While many people may have asymptomatic Tarlov cysts discovered incidentally during imaging, these lesions become clinically significant when they enlarge and exert pressure on the spinal nerves. Because these cysts are located within the nerve root sheath, they contain cerebrospinal fluid (CSF). When a Tarlov cyst grows, it can cause chronic, debilitating pain, numbness, and motor weakness in the lower extremities, buttocks, and pelvic region.

Affected Systems and Pathophysiology

The primary impact of a Tarlov cyst involves the central nervous system, specifically the nerve roots exiting the spinal cord. As the cysts expand, they can erode the surrounding bone and compress nearby structures, affecting the muscular system (through weakness or reflex loss) and the urinary or digestive systems (by disrupting the nerve signals that control bladder and bowel function). The underlying mechanism is often attributed to a "ball-valve" effect, where CSF flows into the cyst but is unable to flow back out, causing the cyst to inflate.

Epidemiology and Diagnosis

The exact prevalence of symptomatic Tarlov cyst cases is difficult to determine because many remain undiagnosed or asymptomatic. However, studies suggest that approximately 1–5% of the general population may have these cysts, with women being diagnosed more frequently than men. Symptoms typically manifest in adulthood, often between the ages of 30 and 60. Unlike other spinal cysts, a Tarlov cyst is specifically defined by its location within the nerve root sheath, which distinguishes it from meningeal or arachnoid cysts.

Medical Disclaimer: This information is for educational purposes and should not replace professional medical advice, diagnosis, or treatment. Always consult with a qualified neurosurgeon or physician regarding your specific health concerns.

References

NIH Genetic and Rare Diseases Information Center (GARD)

Orphanet: The portal for rare diseases and orphan drugs

The Tarlov Cyst Disease Foundation

Author: DiseaseMaps Editorial Team

Reviewed against authoritative medical sources (NIH GARD, Orphanet, OMIM)

Last updated: 2026-04-06

Sources cited: NIH Genetic and Rare Diseases Information Center (GARD) · Orphanet: The portal for rare diseases and orphan drugs · The Tarlov Cyst Disease Foundation

Medical disclaimer: This information does not substitute professional medical advice. Always consult your doctor before making health decisions.

Source: DiseaseMaps.org

Tharlov cysts are fluid filled sacs of the nerveroots, on sacral (or the coccygeal nerve roots) and they can be multiple. They arise on the posterior root or ganglion or both were involved, Al cysts contains either a complete nerve, or nerve fibers are splayed all over the cyst wall.
TCs arise as a result of fluid becoming trapped in a nerve root. The work of Sun et al., who excised microscopically analyzed TCs from resected TCs, increased the understanding of the mechanisms underlying the cyst formation. The upright position of the human causes the physiological hydrostatic pressure in the terminal dural sac to be high. Under increased pressure, the lumbar and sacral sheaths of the nerve roots, which contain the nerve root fibers and exit the terminal dural sac, may begin to enlarge. Eventually, for unknown reasons, fluid can become trapped between the endoneurium and the perineurium and in some of these cases they can evolve into cyst-like structures: the so-called perineural cysts or Tarlov cysts. This expansion of the nerve root sheath may be enhanced by congenital connective tissue weakness as large TCs have been found to occur more frequently in patients with hypermobility and connective tissue disorders.

Posted Jul 23, 2021 by Stichting Overdruksyndroom NL

Tarlov cysts are fluid-filled nerve root cysts found most commonly at the sacral level of the spine – the vertebrae at the base of the spine. These cysts typically occur along the posterior nerve roots. Cysts can be valved or nonvalved. The main feature that distinguishes Tarlov cysts from other spinal lesions is the presence of spinal nerve root fibers within the cyst wall or in the cyst cavity itself.

Due to the close proximity to the lower pelvic region, patients may be misdiagnosed with herniated lumbar discs, arachnoiditis and in females, gynecological conditions. An accurate diagnosis may be further complicated if the patient has another condition that affects the same region.

Posted Jan 20, 2018 by dhedge42 2500

It is a bulbous stretching of the nerve root sheath that fills with spinal fluid that puts pressure on your nerves. They can cause bone eroding, bladder and bowel issues, and genital issues. Again they cannot be removed but there are surgery options.

Posted Jun 18, 2018 by Ze 2520

A tarlov cyst is a pocket that inflates causing pressure on your nerves that in turn wreak havoc in the body

Posted Jun 19, 2018 by Debbie Dronfield 2500

Where cerebral spinal fluid collects at the nerve root causing a cyst

Posted Jun 19, 2018 by Lynn 2500

They are a spinal cord nerve root aneurysm.

Posted Nov 19, 2018 by Kelly 5450

Tarlov cysts are fluid-filled sacs that affect the nerve roots of the spine, especially near the base of the spine (sacral region). Individuals may be affected by multiple cysts of varying size. Symptoms can occur depending upon the size and specific location of the cyst. Generally, the larger a Tarlov cyst is, the more likely it is to cause symptoms. Symptoms sometimes caused by Tarlov cysts include pain in the area served by the affected nerves, numbness and altered sensation, an inability to control bladder and bowel movements (incontinence), impotence, and, rarely, weakness in the legs. Small, asymptomatic cysts can slowly increase in size eventually causing symptoms. The exact cause of Tarlov cysts is unknown, but they may occur due to variation in normal development of the nerve sheath. Tarlov cysts were first described in the medical literature in 1938.

Posted Dec 10, 2019 by Jess Carhart 2500

Tarlov cysts are fluid-filled nerve root cysts found most commonly at the sacral level of the spine – the vertebrae at the base of the spine. These cysts typically occur along the posterior nerve roots. Cysts can be valved or nonvalved.

Posted Jul 22, 2021 by Michelle Tamplin 2500

Tarlov cysts (TCs), or perineural cysts, are spinal meningeal cysts that contain nerve root fibers, or a nerveroot in the cyst themselves.. They originate from dilatations of the nerve root sheath in the ganglion of the dorsal roots and are most commonly identified in the sacrum. But they can occur on every nerveroot which leaves the spinal canal.

Posted Jul 25, 2021 by SOSNL 2500

Een Tarlov cyste is een met vocht gevulde zwelling van een zenuwwortel aan de onderkant van het ruggenmerg. De cysten kunnen tot aanhoudende klachten in het gebied van geslachtsorganen en anus, of tot klachten die lijken op die van een rughernia leiden..

Posted Jul 26, 2021 by Founder SOSNL 2500

A Tarlov cyst is a dilation of the nerve root sheath or outer covering of the nerve. Cerebral spinal fluid gets trapped inside the sheath and forms a cyst. The fluid in the cyst can put pressure on the nerve inside and on the adjacent nerve roots and cause debilitating symptoms. They can occur anywhere along the spine where there are nerve roots. They are most prevalent in the sacrum or base of the spine. The cyst is the nerve and therefore cannot be cut out.

Posted Jul 27, 2021 by KetoGma 2500

They are balloon like cysts formed in the nerve roots, mostly is sacral area but they can be anywhere in the spine. They are filled with cefaloraquidian liquid and they also contain nerve fibers, difficult to treat

Posted Oct 25, 2022 by Tania 2500