[Expert evaluation in bony injuries of the spine].

The conventional way of appreciating working capacity is no longer satisfying considering the improved diagnostic tools with increasing frequency of various deformities, instability and ankylosis and their combinations. As in the evaluation of peripheral joint function a concept is proposed, which is based on the structural changes in the motion segments. The concept is practicable in all parts of the vertebral column and allows a differentiated judgement within the usual percentages.