A burst fracture is a severe injury to the spinal column resulting from a powerful, high-energy impact transmitted along the spine. This trauma compromises the structural integrity of a vertebra, the bony building blocks that protect the spinal cord. Because of the potential for damage to delicate neural structures, a burst fracture requires immediate medical attention.
Anatomical Description
A burst fracture involves the entire vertebral body shattering in multiple directions, distinguishing it from a simple compression fracture. In a compression fracture, only the front portion of the vertebra collapses, while the posterior wall remains intact. A burst fracture involves the failure of both the anterior and middle columns of the spine, leading to a loss of height across the entire bone.
The danger of this fracture is the displacement of bone fragments backward toward the spinal cord (retropulsion). These fragments can intrude into the spinal canal, placing direct pressure on the spinal cord or the nerve roots. This displacement is the primary cause of neurological symptoms and determines the instability of the injury. Burst fractures most commonly occur in the thoracolumbar region, with the first lumbar vertebra (L1) being a frequent site of injury.
Causes and Immediate Symptoms
A burst fracture results from a high-energy axial load, where a powerful force is applied vertically along the spine. Common scenarios include severe motor vehicle accidents involving rapid deceleration, or falls from a significant height where a person lands on their feet or buttocks. The intense, sudden compression exceeds the structural capacity of the vertebral body, causing it to fail and fragment.
Severe back pain localized to the fracture site is the most immediate symptom, often worsening with movement. Because bone fragments can press on the spinal cord or nerves, neurological symptoms can manifest rapidly. Patients may experience radiating pain, numbness, or tingling sensations in the extremities.
More concerning symptoms involve muscle weakness, difficulty moving the limbs, or complete paralysis below the injury level. In severe cases, significant spinal cord compromise can lead to a loss of normal bowel or bladder control, which signals a serious neurological emergency. The severity of these neurological deficits correlates directly with the degree of retropulsion and spinal canal compromise.
Diagnostic Procedures
Confirming a burst fracture begins with a thorough neurological examination conducted by medical professionals. This initial assessment systematically tests the patient’s motor strength, sensation, and reflexes to identify existing neurological deficits. The examination establishes a baseline for nerve function and guides the necessity for urgent intervention.
Initial imaging involves X-rays, which show the loss of vertebral height and general spinal alignment. However, a Computed Tomography (CT) scan is the primary tool used to characterize the fracture pattern in detail. The CT scan provides cross-sectional images effective at visualizing shattered bone fragments and accurately measuring the extent of retropulsion into the spinal canal.
Magnetic Resonance Imaging (MRI) plays an important role in the diagnostic process. Unlike CT, MRI excels at visualizing soft tissues, which is crucial for assessing the integrity of spinal ligaments and damage to the spinal cord or nerve roots. An MRI can detect spinal cord bruising, swelling, or direct compression, providing information missed by bone-focused CT imaging alone. Combining these studies allows the care team to determine the fracture’s stability and the best course of management.
Treatment Approaches
Treatment for a burst fracture is determined primarily by two factors: the stability of the spinal column and the presence or absence of neurological deficits.
Fractures considered stable, with minimal bone fragment intrusion into the spinal canal and no neurological symptoms, may be managed conservatively. Non-surgical management involves immobilizing the spine, often with a rigid external brace (such as a thoracolumbar sacral orthosis), to prevent further collapse and promote bony healing.
Conservative treatment also includes aggressive pain management and restricted physical activity for a period of several weeks to months. The goal of this approach is to allow the fracture to heal naturally while maintaining spinal alignment and preventing any secondary injury to the neural structures.
Patients undergoing this treatment pathway generally face physical restrictions for an extended recovery period, often ranging from three to six months.
Surgical intervention is necessary when the fracture is unstable or when bone fragments cause significant compression of the spinal cord or nerve roots, resulting in neurological deficits. The primary goals of surgery are to decompress the neural elements and stabilize the spinal column. Decompression involves carefully removing retropulsed bone fragments and other material pressing on the spinal cord.
Stabilization is achieved through spinal fusion, where metal instrumentation (such as rods and screws) rigidly fixes the fractured vertebra to adjacent healthy vertebrae. This internal fixation restores the spine’s load-bearing capacity and prevents future deformity. Following surgery, the patient requires a period of recovery and rehabilitation to regain strength and mobility.