Tethered spinal cord syndrome
Encyclopedia
Tethered spinal cord syndrome or occult spinal dysraphism sequence refers to a group of neurological disorder
s related to malformations of the spinal cord. The various forms include: tight filum terminale, lipomeningomyelocele, split cord malformations, dermal sinus tracts, dermoids, and cystoceles. All of the forms have in common the pulling of the spinal cord at the base of the spinal canal, literally a "tethered cord". The spinal cord normally hangs loose in the canal, free to move up and down with growth and bending and stretching, a tethered cord is held taut at the end. In children, a tethered cord can cause the spinal cord to stretch as they grow, in adults the spinal cord will stretch in the course of normal activity, usually leading to progressive spinal cord damage if left untreated. It is often associated with the closure of a spina bifida
, although not always depending on the form it takes; for example it can be congenital such as in tight filum terminale, or the result of injury later in life.
s, hairy patches, dimples, or fatty tumours on the lower back; foot and spinal deformities; weakness in the legs; low back pain; scoliosis; and incontinence
. Tethered spinal cord syndrome may go undiagnosed until adulthood, when sensory and motor problems and loss of bowel and bladder control emerge. This delayed presentation of symptoms is related to the degree of strain placed on the spinal cord over time. Tethered spinal cord syndrome appears to be the result of improper growth of the neural tube during fetal development
, and is closely linked to spina bifida
. Tethering may also develop after spinal cord injury and scar tissue can block the flow of fluids around the spinal cord. Fluid pressure may cause cysts to form in the spinal cord, a condition called syringomyelia
. This can lead to additional loss of movement or feeling, or the onset of pain or autonomic
symptoms.
In adults, onset of symptoms typically include severe pain (in the lower back and radiating into the legs, groin, and perineum), bilateral muscle weakness and numbness, loss of feeling and movement in lower extremities, and bladder and/or bowel incontinence. Neurological symptoms can include a mixed picture of upper and lower motor neuron findings, such as amyotrophy
, hyperreflexia
, and pathologic plantar response, occurring in the same limb. Profound sensory changes, such as loss of pain, temperature, and proprioceptive sensations, are common. Last, progressive symptoms of a neuropathic bladder are noted on over 70% of adult patients, versus only 20% to 30% of children. These symptoms include urinary frequency and urgency, feeling of incomplete voiding, poor voluntary control, and urge and stress incontinence. Chronic recurrent infections are common and occasionally lead to nephrolithiasis (kidney stone
s), renal failure
, or renal transplantation. Female patients also give a history of ineffective labor and postpartum rectal prolapse
, presumably due to an atonic pelvic floor.
which should also be screened for upon a positive TCS diagnosis.
Other treatment is symptomatic and supportive. NSAIDs, opiates, synthetic opiates, Cox II inhibitors, off-label applications of tricyclic anti-depressants combined with anti-seizure compounds have yet to prove they are of value in treatment of this affliction's pain manifestations. There is anecdotal evidence that TENS units may benefit some patients.
Treatment may be needed in adults who, while previously asymptomatic, begin to experience pain, lower back degeneration, scoliosis
, neck and upper back problems and incontinence
and bladder control issues. Surgery on adults with minimal symptoms is somewhat controversial, for example Columbia University Dept of Neurosurgery says "For the child that has reached adult height with minimal if any symptoms, some neurosurgeons would advocate careful observation only," however surgery for those who have symptoms is not controversial.
This syndrome was first noticed in the late 19th century and while information has been available for years, little widespread blind research has been done. More research has been called for and many studies have been done by doctors with great results. There is a low morbidity rate and no known complications have been documented other than those from any type of typical back surgery. The association of this condition with others has been noticed and also needs further research to understand the relations. Spinal compression and the resulting relief is a known issue with this disorder. Like with the early-onset form, this disease form is linked to the Arnold-Chiari malformation
, in which the brain is pulled or lowers into the top of the spine.
(which joins the spinal cord to the backbone) thickens or hardens and causes downward pressure on the spinal cord. This can actually cause scoliosis
as well as most of the other symptoms of the more typical tethered cord. This syndrome was first noticed and documented in the late 19th century.
Neurology
Neurology is a medical specialty dealing with disorders of the nervous system. Specifically, it deals with the diagnosis and treatment of all categories of disease involving the central, peripheral, and autonomic nervous systems, including their coverings, blood vessels, and all effector tissue,...
s related to malformations of the spinal cord. The various forms include: tight filum terminale, lipomeningomyelocele, split cord malformations, dermal sinus tracts, dermoids, and cystoceles. All of the forms have in common the pulling of the spinal cord at the base of the spinal canal, literally a "tethered cord". The spinal cord normally hangs loose in the canal, free to move up and down with growth and bending and stretching, a tethered cord is held taut at the end. In children, a tethered cord can cause the spinal cord to stretch as they grow, in adults the spinal cord will stretch in the course of normal activity, usually leading to progressive spinal cord damage if left untreated. It is often associated with the closure of a spina bifida
Spina bifida
Spina bifida is a developmental congenital disorder caused by the incomplete closing of the embryonic neural tube. Some vertebrae overlying the spinal cord are not fully formed and remain unfused and open. If the opening is large enough, this allows a portion of the spinal cord to protrude through...
, although not always depending on the form it takes; for example it can be congenital such as in tight filum terminale, or the result of injury later in life.
Signs and symptoms
In children, symptoms may include lesionLesion
A lesion is any abnormality in the tissue of an organism , usually caused by disease or trauma. Lesion is derived from the Latin word laesio which means injury.- Types :...
s, hairy patches, dimples, or fatty tumours on the lower back; foot and spinal deformities; weakness in the legs; low back pain; scoliosis; and incontinence
Urinary incontinence
Urinary incontinence is any involuntary leakage of urine. It is a common and distressing problem, which may have a profound impact on quality of life. Urinary incontinence almost always results from an underlying treatable medical condition but is under-reported to medical practitioners...
. Tethered spinal cord syndrome may go undiagnosed until adulthood, when sensory and motor problems and loss of bowel and bladder control emerge. This delayed presentation of symptoms is related to the degree of strain placed on the spinal cord over time. Tethered spinal cord syndrome appears to be the result of improper growth of the neural tube during fetal development
Fetal development
Prenatal or antenatal development is the process in which a human embryo or fetus gestates during pregnancy, from fertilization until birth. Often, the terms fetal development, foetal development, or embryology are used in a similar sense.After fertilization the embryogenesis starts...
, and is closely linked to spina bifida
Spina bifida
Spina bifida is a developmental congenital disorder caused by the incomplete closing of the embryonic neural tube. Some vertebrae overlying the spinal cord are not fully formed and remain unfused and open. If the opening is large enough, this allows a portion of the spinal cord to protrude through...
. Tethering may also develop after spinal cord injury and scar tissue can block the flow of fluids around the spinal cord. Fluid pressure may cause cysts to form in the spinal cord, a condition called syringomyelia
Syringomyelia
Syringomyelia is a generic term referring to a disorder in which a cyst or cavity forms within the spinal cord. This cyst, called a syrinx, can expand and elongate over time, destroying the spinal cord. The damage may result in pain, paralysis, weakness, and stiffness in the back, shoulders, and...
. This can lead to additional loss of movement or feeling, or the onset of pain or autonomic
Autonomic nervous system
The autonomic nervous system is the part of the peripheral nervous system that acts as a control system functioning largely below the level of consciousness, and controls visceral functions. The ANS affects heart rate, digestion, respiration rate, salivation, perspiration, diameter of the pupils,...
symptoms.
In adults, onset of symptoms typically include severe pain (in the lower back and radiating into the legs, groin, and perineum), bilateral muscle weakness and numbness, loss of feeling and movement in lower extremities, and bladder and/or bowel incontinence. Neurological symptoms can include a mixed picture of upper and lower motor neuron findings, such as amyotrophy
Amyotrophy
Amyotrophy is progressive wasting of muscle tissues. Muscle pain is also a symptom. It can occur in middle age males with type 2 diabetes. It also occurs with Motor Neuron Disease.-See also:* Diabetic amyotrophy* Monomelic amyotrophy...
, hyperreflexia
Hyperreflexia
Hyperreflexia is defined as overactive or overresponsive reflexes. Examples of this can include twitching or spastic tendencies, which are indicative of upper motor neuron disease as well as the lessening or loss of control ordinarily exerted by higher brain centers of lower neural pathways...
, and pathologic plantar response, occurring in the same limb. Profound sensory changes, such as loss of pain, temperature, and proprioceptive sensations, are common. Last, progressive symptoms of a neuropathic bladder are noted on over 70% of adult patients, versus only 20% to 30% of children. These symptoms include urinary frequency and urgency, feeling of incomplete voiding, poor voluntary control, and urge and stress incontinence. Chronic recurrent infections are common and occasionally lead to nephrolithiasis (kidney stone
Kidney stone
A kidney stone, also known as a renal calculus is a solid concretion or crystal aggregation formed in the kidneys from dietary minerals in the urine...
s), renal failure
Renal failure
Renal failure or kidney failure describes a medical condition in which the kidneys fail to adequately filter toxins and waste products from the blood...
, or renal transplantation. Female patients also give a history of ineffective labor and postpartum rectal prolapse
Rectal prolapse
Rectal prolapse normally describes a medical condition wherein the walls of the rectum protrude through the anus and hence become visible outside the body.-Types:There are three chief conditions which come under the title rectal prolapse:...
, presumably due to an atonic pelvic floor.
Treatment
Because neurological deficits are generally irreversible, early surgery is recommended when symptoms begin to worsen. In children, early surgery is recommended to prevent further neurological deterioration, including but not limited to chronic urinary incontinence. In adults, surgery to free (detether) the spinal cord can reduce the size and further development of cysts in the cord and may restore some function or alleviate other symptoms. Tethered cord syndrome is causally linked to Chiari Malformation and any affirmative diagnosis of TCS must be followed by screening for Chiari's several degrees. TCS may also be related to Ehlers-Danlos syndromeEhlers-Danlos syndrome
Ehlers–Danlos syndrome is a group of inherited connective tissue disorders, caused by a defect in the synthesis of collagen . The collagen in connective tissue helps tissues to resist deformation...
which should also be screened for upon a positive TCS diagnosis.
Other treatment is symptomatic and supportive. NSAIDs, opiates, synthetic opiates, Cox II inhibitors, off-label applications of tricyclic anti-depressants combined with anti-seizure compounds have yet to prove they are of value in treatment of this affliction's pain manifestations. There is anecdotal evidence that TENS units may benefit some patients.
Treatment may be needed in adults who, while previously asymptomatic, begin to experience pain, lower back degeneration, scoliosis
Scoliosis
Scoliosis is a medical condition in which a person's spine is curved from side to side. Although it is a complex three-dimensional deformity, on an X-ray, viewed from the rear, the spine of an individual with scoliosis may look more like an "S" or a "C" than a straight line...
, neck and upper back problems and incontinence
Urinary incontinence
Urinary incontinence is any involuntary leakage of urine. It is a common and distressing problem, which may have a profound impact on quality of life. Urinary incontinence almost always results from an underlying treatable medical condition but is under-reported to medical practitioners...
and bladder control issues. Surgery on adults with minimal symptoms is somewhat controversial, for example Columbia University Dept of Neurosurgery says "For the child that has reached adult height with minimal if any symptoms, some neurosurgeons would advocate careful observation only," however surgery for those who have symptoms is not controversial.
This syndrome was first noticed in the late 19th century and while information has been available for years, little widespread blind research has been done. More research has been called for and many studies have been done by doctors with great results. There is a low morbidity rate and no known complications have been documented other than those from any type of typical back surgery. The association of this condition with others has been noticed and also needs further research to understand the relations. Spinal compression and the resulting relief is a known issue with this disorder. Like with the early-onset form, this disease form is linked to the Arnold-Chiari malformation
Arnold-Chiari malformation
Arnold–Chiari malformation, or often simply Chiari malformation, is a malformation of the brain. It consists of a downward displacement of the cerebellar tonsils through the foramen magnum , sometimes causing non-communicating hydrocephalus as a result of obstruction of cerebrospinal fluid outflow...
, in which the brain is pulled or lowers into the top of the spine.
Prognosis
The natural course of the disorder is progressive with age, but the aforementioned treatments can help prevent or sometimes relieve symptoms. With treatment, individuals with tethered spinal cord syndrome have a normal life expectancy. However, most neurological and motor impairments are irreversible.Occult tight filum terminale
In this variation, the filum terminaleFilum terminale
The filum terminale , is a delicate strand of fibrous tissue, about 20 cm. in length, proceeding downward from the apex of the conus medullaris. It gives longitudinal support to the spinal cord and consists of two parts:...
(which joins the spinal cord to the backbone) thickens or hardens and causes downward pressure on the spinal cord. This can actually cause scoliosis
Scoliosis
Scoliosis is a medical condition in which a person's spine is curved from side to side. Although it is a complex three-dimensional deformity, on an X-ray, viewed from the rear, the spine of an individual with scoliosis may look more like an "S" or a "C" than a straight line...
as well as most of the other symptoms of the more typical tethered cord. This syndrome was first noticed and documented in the late 19th century.
External links
- Chiari & Syringomyelia Foundation
- More Chirari information w/Tethered cord article
- National institute of Health page
- NPR show on it
http://www.aans.org/education/journal/neurosurgical/Aug07/23-2-5-1214.pdf Recent research articles