Measurement of strength and stability of suture versus AO screw fixation of Mitchell's osteotomy: a cadaveric study

Abstract

We present the results of a biomechanical study investigating the strength and stability of the Mitchell's osteotomy when fixed either by a suture or an AO screw. The average force to failure of the suture fixation is small with a correspondingly large displacement indicating the need for protection of this fixation method with cast immobilization. In contrast, the screw fixation failed at forces approaching those expected under the foot when walking and displaced less prior to failure. It is suggested that screw fixation is stronger and more stable than the traditional method of fixation of Mitchell's osteotomy and, therefore, may allow early heel weight bearing mobilization without the need for a cast.