A spinal stroke, also known as a spinal cord infarction, is a disruption of blood flow to the spinal cord that causes tissue damage and impaired function. This rare condition specifically affects the spinal cord, leading to a sudden loss of oxygen and nutrients in the nerve tissue. Accounting for less than one percent of all strokes, it represents a serious medical emergency requiring rapid diagnosis and intervention. The consequences of this interruption can be severe, impacting the body’s ability to send and receive signals below the level of the injury.
Understanding Spinal Cord Ischemia
The fundamental mechanism behind a spinal stroke is ischemia, the restriction of blood supply to tissue, causing a shortage of oxygen and glucose needed for cellular metabolism. This typically results in an infarction, or the death of tissue, due to the lack of blood flow. The spinal cord’s blood supply relies heavily on the anterior spinal artery (ASA), which runs down the front of the cord and supplies the anterior two-thirds of the tissue.
The anterior spinal artery territory is particularly susceptible to ischemia because it is supplied by a single artery with limited collateral circulation, especially in the mid-thoracic region. When this artery or one of its feeding branches becomes blocked or experiences severely reduced flow, the nerve tissue it supplies begins to die.
Identifying the Causes and Risk Factors
Spinal strokes are most often caused by conditions that compromise blood flow through the major arteries of the body, particularly the aorta. Aortic surgery, especially procedures involving the thoracoabdominal aorta, is considered the most common cause of non-traumatic spinal cord infarction. This is due to the potential for prolonged clamping of the aorta or direct injury to the smaller feeding arteries, such as the artery of Adamkiewicz.
Atherosclerosis, the hardening and narrowing of arteries due to plaque buildup, is a primary risk factor because it can lead to the formation of blood clots that travel to the spinal arteries. Conditions like high blood pressure, high cholesterol, and diabetes contribute to this arterial damage and increase risk. Furthermore, a sudden and prolonged drop in blood pressure, known as systemic hypotension, can cause an infarction even without a physical blockage.
Less common causes include aortic dissection, a tear in the aorta’s inner layer, or embolisms originating from the heart. These emboli are clots that break off and travel through the bloodstream until they lodge in a smaller spinal artery. In a notable number of cases, the exact cause of a spinal cord infarction remains undetermined.
Recognizing the Sudden Symptoms
The onset of a spinal stroke is typically abrupt and severe, demanding immediate medical attention. The most common initial symptom is sudden, intense pain in the back or neck, often described as a sharp or burning sensation at the level of the injury. This pain can radiate into the arms or legs.
Rapid onset of muscle weakness is a hallmark sign, frequently progressing to bilateral leg weakness or complete paralysis within minutes to a few hours. Patients also experience a loss of sensation below the affected level, including the inability to feel pain or distinguish temperature changes. Immediate dysfunction of the bladder and bowel is also common.
Diagnosis and Acute Medical Management
Diagnosis begins with a thorough physical and neurological examination to assess the pattern of sensory and motor loss, which helps pinpoint the affected area. Because the symptoms mimic other serious conditions like spinal cord compression or hemorrhage, rapid imaging is necessary to confirm the diagnosis and rule out alternative causes.
Magnetic Resonance Imaging (MRI) is the definitive diagnostic tool, visualizing spinal cord tissue and showing signs of infarction, which may appear as specific bright signals on T2-weighted images. Initial MRI scans can sometimes be unremarkable in the first few hours, requiring a high degree of clinical suspicion. A CT scan may also be used to quickly rule out conditions like spinal fractures or bleeding.
Acute medical management is primarily supportive, focusing on stabilizing the patient and preserving the remaining neural tissue. This involves careful management of blood pressure to ensure adequate blood flow. Unlike many brain strokes, specific clot-busting medications (thrombolytics) are not routinely used due to limited data on their safety and effectiveness.
In cases where a clear mechanical cause, such as a clot or compression, is identified, surgery may be necessary to restore blood flow or relieve pressure. Otherwise, treatment focuses on maintaining high oxygen levels and addressing underlying risk factors. The immediate goal is to limit the extent of the damage.
Recovery and Rehabilitation Outlook
Recovery from a spinal stroke is highly variable and depends significantly on the initial severity and location of the spinal cord damage. While some individuals may experience a substantial improvement in function, others may be left with long-term complications, including permanent paralysis or chronic pain. The recovery process often continues for months to years after the initial event.
Rehabilitation forms a cornerstone of the recovery phase.
Rehabilitation Components
- Physical therapy (PT) is employed to strengthen muscles and improve balance.
- Occupational therapy (OT) helps patients regain the skills needed for daily living activities.
- Managing secondary complications, such as spasticity, chronic pain, and bladder dysfunction, is a continuous part of the care plan.
Meaningful functional recovery is possible for a substantial minority of patients, even those with severe initial deficits. While some individuals may need assistive devices for mobility, others may eventually regain full independence. The prognosis is generally considered better for spinal strokes than for brain strokes.