Reverse total shoulder arthroplasty: research models.

PURPOSE: the past decade has seen a considerable increase in the use of research models to study reverse total shoulder arthroplasty (RTSA). Nevertheless, none of these models has been shown to completely reflect real in vivo conditions.
METHODS: we performed a systematic review of the literature matching the following key words: "reverse total shoulder arthroplasty" or "reverse total shoulder replacement" or "reverse total shoulder prosthesis" and "research models" or "biomechanical models" or "physical simulators" or "virtual simulators". The following databases were screened: Medline, Google Scholar, EMBASE, CINAHIL and Ovid. We identified and included all articles reporting research models of any kind, such as physical or virtual simulators, in which RTSA and the glenohumeral joint were reproduced.
RESULTS: computer models and cadaveric models are the most commonly used, and they were shown to be reliable in simulating in vivo conditions. Bone substitute models have been used in a few studies. Mechanical testing machines provided useful information on stability factors in RTSA.
CONCLUSION: because of the limitations of each individual model, additional research is required to develop a research model of RTSA that may reduce the limitations of those presently available, and increase the reproducibility of this technique in the clinical setting.