[Classification of periprosthetic shoulder fractures]

The key targets in the treatment of periprosthetic humeral fractures (PHF) are the preservation of bone, successful bony consolidation and provision of a stable anchoring of the prosthesis with the major goal of restoring the shoulder-arm function. A substantial problem of periprosthetic shoulder fractures is the fact that treatment is determined not only by the fracture itself but also by the implanted prosthesis and its function. Consequently, the exact preoperative shoulder function and, in the case of an implanted anatomical prosthesis, the status and function of the rotator cuff need to be assessed in order to clarify the possibility of a secondarily occurring malfunction. Of equal importance in this context is the type of implanted prosthesis. The existing classification systems of Wright and Cofield, Campbell et al., Groh et al. and Worland et al. have several drawbacks from a shoulder surgeon's point of view, such as a missing reference to the great variability of the available prostheses and the lack of an evaluation of rotator cuff function. The presented 6‑stage classification for the evaluation of periprosthetic fractures of the shoulder can be considered just as simple or complex to understand as the classification of the working group for osteosynthesis problems (AO, Arbeitsgemeinschaft für Osteosynthesefragen), depending on the viewpoint. From our point of view the classification presented here encompasses the essential points of the existing classification systems and also covers the otherwise missing points, which should be considered in the assessment of such periprosthetic fractures. The classification presented here should provide helpful assistance in the daily routine to find the most convenient form of therapy.