Thoracic myelopathy is a neurological condition that arises from significant compression of the spinal cord within the thoracic spine. This section of the spine is located in the mid-back, and the compression obstructs nerve pathways, interrupting signals sent from the brain to various parts of the body. This condition is distinct because the thoracic spine is naturally more rigid than the neck or lower back.
Common Symptoms of Thoracic Myelopathy
The presentation of thoracic myelopathy often involves a gradual onset of symptoms that can worsen over months or even years. Individuals may first notice sensory changes, such as numbness, tingling, or a peculiar band-like sensation that wraps around the torso. This sensation corresponds to the specific level of the spinal cord where the compression is occurring. These sensory disturbances are often accompanied by pain in the mid-back, lower back, or legs.
As the condition progresses, motor function becomes increasingly affected. Leg weakness and stiffness, known as spasticity, can make walking difficult and lead to problems with balance and coordination. Fine motor skills, although less commonly associated with thoracic issues compared to cervical myelopathy, can also be impacted.
In more advanced stages, the compression can interfere with the nerves that control autonomic functions. This can lead to issues with bowel or bladder control, such as increased urgency or incontinence. The symptoms of thoracic myelopathy affect the body at and below the level of the spinal cord compression, meaning the arms and hands are usually spared.
Underlying Causes
The compression of the spinal cord in the thoracic region can stem from several underlying issues, with degenerative changes being the most common cause, particularly in individuals over 50. Spinal stenosis, a gradual narrowing of the spinal canal, is a frequent culprit and can be caused by the thickening of ligaments or the enlargement of facet joints due to osteoarthritis.
Another primary cause is a herniated or bulging disc. The gel-like center of a spinal disc can push through its tough exterior and press directly on the spinal cord. Similarly, the formation of bone spurs, or osteophytes, which are bony growths that develop on the edges of vertebrae, can also encroach upon the spinal canal and lead to compression.
While degeneration accounts for many cases, other conditions can also lead to thoracic myelopathy. Spinal trauma from an accident or fall can cause fractures or dislocations of the vertebrae that compress the spinal cord. In other instances, spinal tumors, whether originating in the spine or metastasizing from cancer elsewhere in the body, can grow into the spinal canal. Inflammatory conditions like rheumatoid arthritis can also contribute to the instability and changes in the spine that result in cord compression.
The Diagnostic Process
A diagnosis of thoracic myelopathy begins with a clinical evaluation. A physician will conduct a detailed review of the patient’s medical history and discuss the timeline and nature of the symptoms. This is followed by a physical and neurological examination to assess the extent of the neurological impact.
The physician will test muscle strength in the legs, check reflexes, and evaluate sensation to touch and vibration. Walking patterns, balance, and coordination are also carefully observed to identify abnormalities. The presence of increased or abnormal reflexes in the extremities can be a sign of spinal cord compression.
Imaging studies are necessary to visualize the spine and confirm the diagnosis. Magnetic Resonance Imaging (MRI) is the preferred method as it provides detailed images of the spinal cord, discs, and surrounding soft tissues, allowing the doctor to pinpoint the exact location and cause of the compression. If an MRI is not possible, a Computed Tomography (CT) scan or a CT myelogram may be used to get a detailed view of the bony structures and the spinal canal.
Treatment Approaches
Treatment for thoracic myelopathy is tailored to the individual’s symptoms and the underlying cause. Non-surgical approaches are aimed at managing symptoms rather than resolving the compression itself. These conservative treatments may include physical therapy to help improve strength, balance, and mobility. Medications such as anti-inflammatory drugs might be used to reduce pain and swelling.
For many individuals, especially when symptoms are progressive, surgery is the recommended course of action. The primary goal of surgical intervention is to decompress the spinal cord, which means creating more space to relieve the pressure on the nerves. This is done to prevent further neurological deterioration. The decision to proceed with surgery is based on the extent of the compression and the impact on the patient’s quality of life.
Several surgical procedures can be used to achieve decompression. A laminectomy is a common procedure where a portion of the vertebral bone called the lamina is removed to enlarge the spinal canal. Other techniques may involve removing a herniated disc or a bone spur that is pressing on the cord.
Recovery and Prognosis
The outlook for individuals with thoracic myelopathy is highly dependent on several factors. Early diagnosis and intervention are strongly linked to more favorable outcomes. The duration and severity of the symptoms before treatment play a significant part in determining the potential for recovery. Patients with milder symptoms and shorter symptom duration before surgery tend to have better results.
Following surgery, the focus shifts to rehabilitation. The recovery process can vary widely among individuals. While the surgery can successfully stop the condition from worsening, the reversal of existing nerve damage is not always possible. Some patients may experience a significant improvement in their symptoms, such as regaining strength and coordination.
The prognosis is influenced by the patient’s overall health and age. The recovery journey often involves physical therapy to maximize functional ability and adapt to any residual neurological deficits. It is important for patients to have realistic expectations, as complete recovery is not guaranteed.