A spinal cord injury (SCI) is a medical condition involving damage to the nerves that transmit signals between the brain and the body. This damage can result from direct trauma to the spinal cord or surrounding bones and tissues. SCIs can lead to temporary or permanent changes in sensation, movement, strength, and various bodily functions below the injury site. Early recognition is important for proper management and to prevent further harm.
Understanding Spinal Cord Injuries
A spinal cord injury involves disruption to the neural tissue within the spinal canal, impacting the transmission of sensory, motor, and autonomic signals. The spinal cord acts as a communication pathway, relaying messages between the brain and body. Damage to this pathway can lead to varied effects depending on the injury’s location and severity.
Spinal cord injuries are categorized as complete or incomplete. A complete spinal cord injury involves a total loss of motor and sensory function below the injury level. Conversely, an incomplete spinal cord injury indicates that some nerve signals can still travel past the injured site, preserving some sensation or movement below the injury level. This distinction is important for understanding potential recovery and guiding treatment.
Observable Indicators of Complete Spinal Cord Injury
The primary finding raising suspicion of a complete spinal cord injury is the total and bilateral loss of all motor, sensory, and autonomic functions below the injury level. This loss must be absolute on both sides of the body.
A key indicator is the complete loss of motor function, presenting as paralysis below the injury, meaning individuals cannot voluntarily move muscles below that point. For example, an injury to the upper spinal cord might cause paralysis in all four limbs (tetraplegia), while a lower spinal cord injury could result in paralysis of the lower body and legs (paraplegia).
Accompanying the motor loss is a complete absence of sensory function, including the inability to feel touch, pain, temperature, or body position (proprioception) below the injury site. This lack of sensation is total and extends across both sides of the body below the specific level of damage.
Immediate signs of autonomic dysfunction also raise suspicion, including a sudden loss of bladder and bowel control. A sudden drop in blood pressure (hypotension) and a slowed heart rate (bradycardia) can indicate neurogenic shock, a serious condition resulting from the disruption of the nervous system’s ability to regulate blood vessel tone. The skin may appear warm and flushed due to the inability of blood vessels to constrict.
Medical Assessment for Suspected Complete SCI
Medical professionals perform a systematic evaluation to confirm a suspected complete spinal cord injury. A neurological examination is a primary step, involving testing motor strength, sensation, and reflexes. Doctors assess motor function by grading muscle strength in key muscle groups on both sides of the body. Sensory function is tested using light touch and pinprick sensations across different dermatomes, which are specific skin areas supplied by single spinal nerves. Evaluating sacral sparing, which involves checking sensation and muscle function in the lowest sacral segments (S4-S5), is important; any preserved function here indicates an incomplete injury.
Imaging studies are essential for visualizing spinal column and cord damage, helping identify the precise location and extent of the injury. X-rays can reveal bony abnormalities like fractures or dislocations. Computed tomography (CT) scans provide detailed images of bone injuries, including fractures and misalignments, and can also detect disc herniations or hematomas. Magnetic resonance imaging (MRI) is considered the gold standard for evaluating soft tissues like the spinal cord, ligaments, and discs, and can show spinal cord compression, edema, or hemorrhage. While observable signs suggest a complete SCI, definitive diagnosis relies on these comprehensive medical assessments.
Immediate Response to Suspected Complete SCI
When a complete spinal cord injury is suspected, immediate and appropriate action is important to prevent further damage. The first step is to call emergency services, such as 911 or the local equivalent, without delay. Stressing the urgency of the situation to the dispatcher is important.
Avoid moving the injured person, as any movement could worsen the spinal cord damage. Instead, stabilize the head and neck by placing heavy towels or rolled sheets on either side, or by manually holding the head and neck to prevent movement. If the person is wearing a helmet, do not remove it, as this could lead to further injury.
While waiting for emergency personnel, basic first aid measures can be considered if trained and without moving the person. Maintaining an open airway is important, but avoid standard head-tilt-chin-lift maneuvers. Instead, use a jaw-thrust maneuver to open the airway if necessary. Keeping the person warm is also important, as individuals with spinal cord injuries, particularly higher-level ones, may experience impaired temperature regulation due to neurogenic shock.