A tethered spinal cord is a neurological condition where the spinal cord is abnormally attached to surrounding tissues within the spinal canal. Normally, the spinal cord floats freely within this protective bony tunnel, allowing for movement as the body grows and moves. This abnormal attachment restricts the spinal cord’s natural movement, causing it to stretch and experience tension. This tension can damage spinal nerves and restrict blood flow, leading to various neurological problems.
Understanding Tethered Spinal Cord
The spinal cord typically ends at the first or second lumbar vertebrae, a structure called the conus medullaris. When tethering occurs, the conus medullaris is pulled lower than its normal position. The “tethering” refers to the spinal cord becoming stuck to the inside of the spinal canal, often by fibrous bands, fatty masses (lipomas), or other abnormal tissues.
This condition can arise in two primary ways: congenitally or acquired. Congenital tethered spinal cord is present at birth and linked to developmental issues during fetal growth. Spina bifida occulta, a mild form of spina bifida, is a common association. Acquired tethered spinal cord develops later in life due to factors like scar tissue formation after spinal surgery, trauma, or tumors.
Recognizing the Signs
The symptoms of a tethered spinal cord vary depending on the individual’s age, as tension on the spinal cord worsens with growth. In infants, common indicators include skin abnormalities on the lower back, such as unusual dimples, raised bumps, birthmarks, or hairy patches over the spine. Other signs include foot deformities, like high arches or curled toes, or leg weakness.
As children grow, symptoms become more pronounced. They may experience back pain radiating down the legs, along with leg weakness, numbness, or abnormal muscle function. Difficulty walking, changes in gait, or the development of an abnormal spinal curve (scoliosis) that progresses are also observed. Bladder and bowel dysfunction, such as incontinence or frequent urinary tract infections, are common due to nerve involvement.
Adults with undiagnosed or progressively worsening tethered spinal cord present with chronic lower back pain. They may also experience leg weakness, numbness, or sensory problems that worsen over time. Bladder and bowel control issues are frequently reported, along with progressive neurological deficits impacting daily activities.
Diagnosis and Treatment Approaches
Diagnosing a tethered spinal cord begins with a thorough physical examination. Healthcare providers look for characteristic skin markers on the lower back and assess neurological function, including muscle strength and reflexes in the legs. Imaging techniques are then used to confirm the diagnosis and pinpoint the exact location and nature of the tethering.
Magnetic Resonance Imaging (MRI) of the spine is considered the gold standard for diagnosing a tethered spinal cord, providing detailed images of the spinal cord and surrounding tissues. For infants, ultrasound may also be used as an initial screening tool, as their spinal structures are not yet fully ossified. Urodynamic studies, which assess bladder function, may also be conducted to evaluate any associated bladder control issues.
The primary treatment for a tethered spinal cord is typically surgical intervention, known as detethering surgery. This procedure aims to release the spinal cord from its abnormal attachments, allowing it to move freely within the spinal canal. The goal of surgery is to prevent further neurological damage, alleviate existing symptoms, and potentially reverse some deficits. While surgery is the main approach, non-surgical management primarily focuses on addressing symptoms if surgery is not indicated or for ongoing care after the procedure.
Living with Tethered Spinal Cord and Long-Term Outlook
The long-term outlook for individuals with a tethered spinal cord varies, but early diagnosis and intervention generally lead to better outcomes. Prompt surgical release of the spinal cord can often prevent or significantly reduce the progression of neurological deficits, and in some cases, symptoms may even improve or reverse. However, the extent of recovery depends on the severity and duration of the tethering before treatment.
Following surgery, some individuals may still experience residual symptoms, requiring ongoing supportive care. This can include physical therapy to improve strength and mobility, occupational therapy to assist with daily activities, or urological management for persistent bladder issues. Regular follow-up appointments with a neurosurgeon are important to monitor for any changes or recurrence of symptoms.
The possibility of retethering exists, particularly in growing children, which may necessitate further surgical intervention. This occurs when scar tissue forms around the spinal cord after the initial surgery, causing it to become re-attached. Despite these possibilities, with proper management and ongoing care, many individuals with a tethered spinal cord can lead fulfilling and active lives.