The poor results using non locked plates in the treatment of more part fractures of the proximal humerus caused the development of locking plates – in our hospital since 1997. In the beginning of this famous “locking-plate era” we used 4.5 mm plates and 6mm screws for the humeral head. The locking screws had been located only in head-part of the plate. In the hope, that all problems would be solved now, we recognized a bundle of new problems. For the different problems it was necessary to change the design and instrumentation several times. Also the operative technique was necessary to change according to failures.

In this lecture we present which problems could be solved and which problems exist furthermore – by indication or technical. Our experience of more than 1000 usage of the locking plate at the proximal humerus let us conclude that there is a great benefit in the treatment of the most elderly patients. The not ignorable failures will be analyzed for giving some tips to prevent them. Some of this failures – collapsing head, penetrating screws, secondary dislocation – can be avoided if we understand the basic cause.