An anterior spinal cord injury involves damage to the front two-thirds of the spinal cord. This portion contains pathways responsible for motor function and certain types of sensation. When this area is damaged, it disrupts signals between the brain and the body, leading to a specific pattern of neurological deficits. The injury is referred to as Anterior Cord Syndrome and is an incomplete spinal cord injury, as some functions controlled by the back portion of the cord are spared.
Causes of an Anterior Spinal Cord Injury
Damage to the anterior spinal cord occurs through two mechanisms: vascular disruption or direct physical trauma. Vascular issues are a frequent cause, stemming from a blockage or reduced blood flow in the anterior spinal artery. This vessel supplies blood to the front section of the spinal cord, and if compromised by conditions like atherosclerosis, a blood clot, or severe low blood pressure, the spinal tissue can suffer an infarction. Complications from surgeries, such as aortic aneurysm repair where the aorta must be clamped, can also interrupt this blood supply.
Direct trauma is the other leading cause. A “burst fracture” of a vertebra can push bone fragments forward into the spinal canal, compressing or lacerating the anterior cord. Flexion injuries of the neck from car accidents or falls can cause similar compression. Penetrating injuries from stabbings or gunshot wounds can also directly damage the anterior structures of the spinal cord.
Associated Symptoms
The primary symptom is the loss of motor function below the level of the injury, which can result in either paraplegia (paralysis of the legs) or quadriplegia (paralysis of all four limbs). This occurs because the corticospinal tracts, which control voluntary muscle movement, are located in the anterior portion of the cord.
Alongside motor deficits, individuals lose the ability to feel pain and temperature below the injury site. The spinothalamic tracts, responsible for relaying these sensations, are also situated in the anterior two-thirds of the cord. A person with this injury might not be able to tell the difference between a sharp object and a dull one, creating a risk for secondary injuries like burns or cuts.
A defining characteristic of this syndrome is the preservation of functions managed by the posterior columns of the spinal cord. This means the sense of vibration, proprioception (the awareness of the position and movement of one’s body parts), and fine touch remain intact. An individual might not be able to move their legs but could still feel the vibration of a tuning fork placed on their ankle.
How Anterior Cord Syndrome is Diagnosed
The diagnostic process begins with a clinical assessment. A physician will perform a neurological examination to map the specific motor and sensory losses. This involves testing muscle strength, checking reflexes, and assessing the patient’s ability to feel pain, temperature, and vibration. The finding of lost motor, pain, and temperature sensation with preserved vibration and position sense strongly suggests an anterior cord injury.
Following the physical exam, medical imaging is used to confirm the diagnosis and identify the cause. Magnetic Resonance Imaging (MRI) is the preferred method because it provides detailed images of soft tissues, allowing doctors to visualize damage to the spinal cord, such as swelling or ischemia. An MRI can show that the damage is confined to the anterior region of the cord. A Computed Tomography (CT) scan is also used, particularly in cases of trauma, as it excels at revealing bone-related injuries like vertebral fractures or dislocations that may be compressing the spinal cord.
Treatment and Management Approaches
Immediate medical care after an anterior spinal cord injury focuses on stabilizing the patient and preventing further damage. This includes immobilizing the spine and managing blood pressure to ensure adequate blood flow to the spinal cord tissue. If the injury is caused by compression, emergency surgery may be performed to decompress the spinal cord and stabilize the vertebrae.
Long-term management shifts to extensive rehabilitation aimed at maximizing functional independence. Physical therapy focuses on exercises to maintain muscle tone, prevent contractures, and improve any residual motor function. Occupational therapy helps individuals adapt to new ways of performing daily activities, often incorporating adaptive equipment to enhance independence.
Rehabilitation also addresses other potential complications, such as:
- Managing bladder and bowel function
- Addressing neuropathic pain
- Providing psychological support
- Helping patients adjust to life changes associated with the injury
Prognosis and Recovery Potential
The long-term outlook for individuals with an anterior spinal cord injury is often challenging, particularly concerning the return of motor function. Because the corticospinal tracts that control movement are directly damaged, the prognosis for regaining strength and mobility below the injury level is less favorable than in other types of incomplete spinal cord injuries. The extent of initial neurological deficit is a strong predictor of the final outcome.
Some sensory recovery, particularly for pain and temperature, may occur in the months following the injury, but motor recovery is limited. Factors such as the patient’s age, overall health, and the intensity of their rehabilitation program can influence the degree of functional improvement. While a full return to pre-injury function is rare, the focus of recovery shifts from regaining lost function to optimizing the abilities that remain.