[Posttraumatic arthrosis of the glenohumeral joint. From partial resurfacing to reverse shoulder arthroplasty].

BACKGROUND: Arthroplasty of symptomatic sequelae after fractures of the proximal humerus is a demanding procedure for surgeons. Exact preoperative planning is crucial in order to achieve acceptable functional results.

OBJECTIVE: Discussion of preoperative considerations in planning the procedure and choosing the appropriate implant taking the osseous anatomy and surrounding soft tissue situation into consideration.

METHODS: Selective literature review and description of personal experience.

RESULTS: The geometry and consolidation status of bone fragments as well as the conditions of the surrounding soft tissue have to be taken into account and influence the choice of implant used. Insufficient planning will not only cause intraoperative technical problems but can also greatly influence the subjective patient assessment of the postoperative outcome. Unequal strain distribution can cause early loosening of components resulting in malfunctioning of the implant. In this respect, knowledge of the position and consolidation status of fractured tuberosities with respect to the humeral shaft is essential and allows an approximate estimation of the achievable outcome. This is taken into account by the classification of Boileau which can also help to decide on which type of implant to use. Because such cases are scarce, reported results in the literature are heterogeneous, which is discussed in this article.

CONCLUSION: Each case needs a thorough and individualized preoperative assessment along with exact planning and should therefore be reserved for experienced shoulder surgeons only.