Hangman fractures

The human spine is formed by individual vertebrae and connective tissue discs in between. The vertebrae form the spinal canal. There are seven cervical, twelve thoracic, and five lumbar vertebrae. The intervertebral discs are the link between the individual vertebral bodies.

The little joints that link the vertebrae together are known as facet joints. They help to stabilize the spine and, together with the intervertebral discs, allow a certain degree of mobility of the spinal cord. The spinal canal should be wide enough to allow nerve roots to float freely in cerebrospinal fluid. The front border of the spinal canal is built by the vertebral bodies and intervertebral discs, the side by the intervertebral joints (facets) and back by the ligamentum flavum (yellow band) and vertebral arches. Discs consist of an outer fibrous ring (annulus fibrosus), which surrounds an inner gel-like center (nucleus pulposus). The spinal cord and nerve roots lie within the spinal canal. The spinal cord extends downwards approx. to the 1st lumbar vertebra. Below, only nerve roots are present in the spinal canal. At the level of the intervertebral disc the nerve roots pass through the neural root foramina to exit the spinal canal. The spinal cord and nerve roots conduct electric-like signals from the skin and joints to the brain, and process of movement is initiated from the brain to the muscles.

The connection between the head and the spine is the atlanto-occipital joint. It consists of the condyles of the occipital bone and the upper joint surfaces of the 1st cervical vertebra. The 1st cervical vertebra is called the atlas. The atlas is connected to the 2nd cervical vertebra (axis) below as well.

Hangman's fracture is a two-sided traumatic fracture of the 2nd cervical vertebra through the pars iterarticularis, often with a forward slide. The classification of Levine and Edwards describes 4 subtypes: (I, II, IIA, III). Type I: <3mm horizontal displacement C2 towards C3, no angulation, C2/3 disc is intact. Type II: >3mm of horizontal displacement C2 towards C3, significant angulation, vertical fracture line, C2/3 disc and posterior longitudinal ligament are disrupted. Type IIA: No horizontal displacement, horizontal fracture line, significant angulation. Type III: Type I fracture + bilateral C2/3 facet dislocation.

Acute compression of the cervical spinal cord

Cervical vertebral fracture

Total or partial paralysis of the hands and feet Insensitivity from the neck down

Pain and stiffness in the neck

The treatment may be non-surgical or surgical.

Type II (>5mm displacement) reduction + surgical fusion Type III reduction + surgical fusion

To restore the protective function of the spine

Posterior C1-C3 fusion

Тranspedicular C2 screw fixation

Anterior C2-3 interbody fusion