[Treatment of the buttonhole phenomenon and similar functional deficiencies]

In the last 20 years we performed 28 operations in cases of button-hole deformities and 6 reconstructive procedures in similar cases caused by destruction of the extensor aponeurosis. In 15 cases of the first mentioned group we reinserted the central slip, which we advanced at the same time by a Lengemann suture, which works also by blocking the PIP-joint; in one case we reinserted according to KAPLAN as modified by VERDAN; in the other 12 cases the deformities were operated according to the methods of DOLPHIN, FOWLER, HELLMANN, LITTLER and EATON, MATEV, PIEPER, NICHOLS, and VERDAN. Based on these experiences the problem of the button-hole deformity can be regarded as sufficiently solved, provided that there is no substantial defect of the central slip. Of all the procedures we prefer the reinsertion of the central slip. For the treatment of deformities with loss of substance we have different surgical procedures at our disposal, the techniques of which are discussed. Due to the small number of cases of buttonhole deformity, there are a priori no optimal conditions for comparative studies, so that we could not evaluate the different surgical methods. Due to this, our therapeutic decision depends much more on the findings in each single case. Even in case of extensive destruction of the extensor aponeurosis we recommend reconstruction. We have seen that the patients in many cases estimate the results more highly than we had supposed, based purely on postoperative measurements.