Fig. 17.1 Unstable odontoid fracture (dens axis fracture of the second cervical vertebral body)
Fig. 17.2 Stabilisation by means of tension screw osteosynthesis (odointoid screw fixation)
The following example shows a typical injury concerning the upper cervical spine (CS) in older patients. Slipping on a carpet or falling on one’s head are frequent accident types. Age-related stiffness of the spine (osteoarthritis/ankylosis) and a reduced bone density (osteoporosis) make the bone more susceptible to sustaining a fracture of the odontoid process (dens axis = tooth or thorn process of the second cervical vertebra) and/or the atlas (first cervical vertebra).
A 70-year-old lady suffers from, among other things, fluctuations in blood circulation and must take medication for the treatment of blood pressure and heart rhythm disturbances. During the night while on her way to the toilet, she slipped and fell, and unfortunately hit her chin on the sink. Her neck is thrust backwards. Despite the immediate severe pain in the neck, especially when moving her head back and forth, the patient cannot visit the doctor until the next morning. The x-rays show a transverse odontoid process fracture of the second cervical vertebral body (Type 2 odontoid fracture according to Anderson and D'Alonzo) (Fig. 17.1).
In this case, conservative fracture treatment e.g. with a stiff neck support (collar) is out of the question, since the X-ray images reveal fracture dislocation and instability. A measurement of bone density shows that it is sufficient, and the fracture type can be adequately treated with screw osteosynthesis of the dens. Under general anaesthesia, the fracture is completely restored by careful setting of the bone and stabilisation with only one tension screw. The fracture gap is closed again and can heal (Fig. 17.2).