Hangman's fracture is the colloquial designation for a both-sided lesion of the axis vertebra, notably of its left and right pars interarticularis. It is the result of a cervical trauma.
Patients suffering only from HF may not experience more discomfort than neck pain and this applies even to the more unstable HF types. Some patients claim neck muscle tension or spasms. Neurological deficits are uncommon because the spinal cord is usually not compromised. Indeed, a HF may even widen the spinal canal at the level of the axis vertebra.
However, HF most frequently result from falls, motor vehicle or sports accidents that may have exposed the (cervical) spine to additional mechanical forces. It is not uncommon to find multiple fractures in one patient. Thus, damage to the spinal cord may occur independent from HF but will most certainly dominate the clinical presentation. Head trauma may yield similarly severe consequences.
Patients who sustained a trauma will also show abrasions, lacerations and other wounds. Fractures are not necessarily limited to the axial skeleton.
HF are identified and classified based on the results of diagnostic imaging. While computed tomography scans and magnetic resonance imaging will yield the desired results, plain radiography is often sufficient . With regards to the latter, anteroposterior, laterolateral and special odontoid views are required to thoroughly evaluate the lesion . Oblique views are not generally recommended, but may be of help to improve the image of posterior parts of the axis vertebra. It has been reported that some HF visible on plain radiographic images have been missed in computed tomography scans. Thus, plain radiography is the diagnostic measure of first choice. Computed tomography may, however, be applied to assess the extent of injury. Strong suspicion for cervical spine fractures that cannot be confirmed in plain radiographic images also indicate computed tomography exams. Employment of magnetic resonance imaging is limited to evaluation of soft-tissue damage, e.g., injury of intervertebral discs and neural tissue. Such an examination is mandatory in patients presenting with neurological deficits.
Treatment depends on the specific type of HF:
Prognosis for HF is good. Only in rare cases do patients present spinal cord injuries that may be associated with permanent quadriplegia. However, patients who present with HF have often been involved in a serious accident and that same accident may have provoked several other injuries that may be considerable more severe than the HF itself. Such comorbidities may significantly worsen the prognosis.
This condition is named for its classic etiology, the hanging of a convict on the gallows. The interaction between the noose that forced the convict to maximally extend their neck, but that also maintained him attached to the gallows, and the force of gravity that accounted for distraction of the cervical spine caused HF to many unfortunate individuals.
Luckily, few people are hanged today. Those that end up in that same position may still sustain that type of fracture (and also cardiovascular and respiratory arrest). Although these individuals most likely won't ever present to a physician, HF are still seen today. Similar mechanical forces may act on the cervical spine of an unrestrained passenger of a motor vehicle is forced into hyperextension either upon striking the dashboard or during severe whiplash injury. Falls may also lead to HF. Moreover, athletes doing hard contact sports such as American football or rugby or divers may sustain HF .
It has been estimated that one out of five spinal fractures corresponds to a cervical spine fracture . The majority of those affect the axis vertebra, but do not necessarily involve its pars interarticularis. Incidence rates regarding the cervical fractures in trauma patients vary from study to study and range between 1 and 4% .
People presenting with HF sustained a severe trauma that typically involved hyperextension of the head and distraction of the cervical spine . These movements put considerable strains on cervical vertebrae, intervertebral discs and joining ligaments, particularly on the second and third vertebra of the cervical spine. As has been described above, hyperextension exposes the anterior longitudinal ligament to increased mechanical stress. Flexion, in contrast, stresses the posterior longitudinal ligament. Both movements result in compression and possibly damage of the intervertebral disk and this condition may leave both vertebrae out of their physiological range of angulation.
These traumatic events have been associated with hanging for a long time. And indeed, some people who found themselves in this situation sustained HF. Surprisingly, forensic science has recently shown that only a small share of hangings truly caused HF . Luckily, they are also rare in falls, motor vehicle and sports accidents. All these situations may, however, have the patient moving rapidly with a maximally extended head. If this movement is suddenly stopped by the patient colliding with an immobile object that hits them under the chin, the neck will be forced into hyperextension. Inertia will continue to drag their body weight into the direction of the abruptly stopped movement, thus distracting the cervical spine.
Accident prevention in professional and recreational activities, while doing sports or riding in a motor vehicle are the best measures to avoid HF. Some activities may require wearing neck protection. From a healthwise point of view, contact sports like American football and rugby cannot be recommended. With regards to motor vehicles, wearing a seat belt decreases the risk of HF significantly.
The term hangman's fracture (HF) refers to the traumatic separation of both pars interarticularis of the second vertebra of the cervical spine, the axis vertebra . This kind of fracture results from hyperextension and subsequent distraction of head and thorax.
These are precisely the movements that occur forcibly when someone is hanged: The noose forces the convict's head into a position of overextension. Simultaneously, the convict's own body weight is pulling downwards while the noose maintains head and neck attached to the gallows, a situation that results in distraction of the cervical spine. Somewhat surprisingly, in this scenario, the fractured vertebra is not the cause of death. Fatal damage to the medulla oblangata or asphyxia due to strangling are the most likely causes of death, and this also applies to deliberate or suicidal hanging as it might still be seen today.
Nowadays, HF rarely result from hanging but rather from motor vehicle or sports accidents.
All these situations may be associated with different mechanical forces and may provoke distinct grades of HF. They are classified according to the following system :
Hangman's fracture (HF) is the colloquial name for an injury of the second vertebra of the cervical spine, the axis vertebra. Per definition, someone who sustained a HF presents with a fracture of both pars interarticularis of this vertebra. The latter term refers to specific anatomic parts of the bone.
As the colloquial name of this condition suggests, this fracture may occur while someone is hanged on the gallows. Here, the noose placed around the convict's neck forces their cervical spine into hyperextension while additional forces act on it: As soon as the convict falls down, their weight pulls down their body, but head and neck are still attached to the gallows. Thus, distraction forces put an additional strain on the spine. The axis vertebra breaks.
Nowadays, HF result from falls, motor vehicle and sports accidents that cause similar situations. Someone may fall down, hit an immobile object with their chin. Their neck will be forced into hyperextension, inertia accounts for distraction of the cervical spine. An individual riding in a car without wearing a seat belt may hit the dashboard with their chin during an accident and suffer the same fracture.
Surprisingly, symptoms associated with a HF are very mild. Most patients claim neck pain, some experience neck muscle tension or spasms. Additional fractures may significantly aggravate the situation.
HF are identified and evaluated in radiographic images. Additional diagnostic measures such as computed tomography scans or magnetic resonance imaging may be required if the physician suspects lesions not visible in plain X-ray images, e.g., injuries of intervertebral disks or neural tissue.
Depending on the severity of the fracture, possible subluxation and displacement of vertebra fragments, conservative or surgical measures will need to be applied. Mild cases may merely require spine traction and wearing a cervical collar, while more complicated fractures need to be stabilized with plates and screws. The decision for a specific therapeutic scheme is based on the risk of spinal cord damage.