A Hangman’s fracture is a severe injury involving a break in the second cervical vertebra (C2). The dramatic name originates from the injury pattern historically associated with judicial hanging, which forced the neck into extreme hyperextension and distraction. While the name suggests a grim past, the vast majority of these fractures today result from high-energy trauma, such as motor vehicle accidents or falls. This serious spinal injury requires immediate medical attention to prevent potential neurological complications.
Anatomy and Technical Definition
The Hangman’s fracture is a break in the axis (C2), the second cervical vertebra. The technical medical name for this injury is Traumatic Spondylolisthesis of the Axis, which describes the slippage of the C2 vertebra over the third cervical vertebra (C3) following trauma. This specific fracture involves the bilateral pars interarticularis, which are the narrow segments of bone connecting the superior and inferior articular facets of C2.
Breaking these bony segments allows the front part of the vertebra to separate from the back, permitting the forward slippage (spondylolisthesis) of the C2 body relative to C3. Because the fracture typically widens the spinal canal at the moment of impact, the spinal cord is often spared immediate injury, a unique feature of this fracture type. The integrity of the C2-C3 disc and its surrounding ligaments ultimately determines the stability of the entire segment.
Mechanism of Injury and Severity Classification
The modern cause of a Hangman’s fracture is typically a high-speed collision, such as a motor vehicle accident. The head strikes an object like a dashboard, forcing the head and neck into violent hyperextension, often combined with an axial (downward) load. This combination of forces compresses the C2 vertebra between the first and third cervical vertebrae, causing the pars interarticularis to fracture. Other common causes include falls from a height or sports injuries that result in a similar whiplash mechanism.
Physicians use the Levine and Effendi classification system to categorize the fracture based on the degree of C2 displacement and angulation.
Fracture Types
A Type I fracture is stable, showing minimal displacement (less than 3 millimeters of forward slippage) and no significant angulation between C2 and C3.
Type II injuries are unstable, marked by greater displacement or angulation, indicating disruption of the C2-C3 disc and ligaments.
A Type IIA fracture shows significant angulation but minimal slippage.
The rare Type III involves severe displacement and angulation, often accompanied by a facet joint dislocation. This classification guides the required treatment plan.
Diagnosis and Management Pathways
Diagnosis typically begins with plain X-rays of the cervical spine, which can reveal the forward slippage of C2 on C3 and the bilateral fractures in the neural arch. A Computed Tomography (CT) scan is the preferred next step, providing detailed, cross-sectional images to precisely delineate the fracture pattern and extent of bony damage. Magnetic Resonance Imaging (MRI) may also be used to assess the integrity of the C2-C3 disc, surrounding ligaments, and the spinal cord itself, especially given the potential for associated soft tissue injury.
Management Based on Stability
Stable Type I fractures are generally managed conservatively with external immobilization, such as a rigid cervical collar, for approximately six to twelve weeks to allow for bone healing.
For unstable Type II and Type IIA fractures, a more rigid external device, like a halo vest, is often necessary. This device fully immobilizes the head and neck for several months.
Surgical stabilization is typically reserved for highly unstable Type II fractures that do not reduce effectively with traction, or for the most severe Type III injuries. In these cases, surgeons perform a fusion procedure, often using screws and rods to permanently join C2 and C3, providing immediate stability to the injured segment.