[Sense and nonsense of knee orthosis]

The trend for early mobility after surgical treatment of knee joint ligament injuries has led to the production of a large number of different braces in recent years. To allow an approximation of the very complex motion of the human knee, the use of braces with so-called physiological hinges has been recommended in the last few years. The authors report on a group of 50 patients who had sustained injuries to the cruciate ligament and had received IOWA knee braces following surgical treatment, the fit being subsequently checked by X-ray. These checks clearly demonstrated that the hinge of the brace hardly coincides with the knee axes and that there were deviations ranging from 1 to 4 cm. The authors therefore come to the conclusion that brace-fit must be checked by X-ray in all cases and that incorrectly fitted braces should be corrected before use. There is so far no evidence that so-called physiological hinges are really superior to braces with single axes. The current trends and developments cannot really be justified as long as there is no guarantee that the axes of brace and human knee coincide both in motion and during weight-bearing.