Da Vinci System: clinical experience with complex proximal humerus fractures.

The purpose of this study is to report the clinical and radiographic outcomes after open reduction and internal fixation of displaced proximal humerus fractures with the "Da Vinci System". It is a triangle-shaped cage whose opposite faces are pierced, and it represents the evolution of a triangle-shaped bone block technique performed in a previous series of 33 patients. The new device is an interesting innovation to treat the difficult problem of fracture fragments reconstruction and stability, metaphyseal bone loss and proximal humerus revascularization. According to the technique, authors position the correct size titanium cage into the metaepiphysis, so that the fragments are reduced upon the cage, and they are stabilized with a minimal osteosynthesis by Kirschner wires, titanium screws or transosseous sutures. If the fracture line involves the proximal portion of the diaphysis, it is possible to use a short low profile plate. Between May 2005 and November 2009, we treated 71 patients (34 men and 37 women), even though we included in our study only 59 patients, who had a minimum follow-up of 12 months. The first patient has been treated in May 2005 and the last one in September 2008. The mean age was 60.8 years (minimum 27, maximum 78). There were 8 displaced 3-part fractures, 20 displaced 4-part fractures, 10 4-part fracture-dislocations, 5 head splitting, 12 unclassified multifragmentary fractures, 1 2-part fracture with multifragmentary calcar and 3 malunions of 4-part fracture. The functional results were evaluated by the Constant score. With a mean follow-up of 24 months (minimum 12, maximum 36 months), the mean Constant score was 80.25. The results were excellent or good in 48 cases, bad in 2 cases and satisfactory in 9; the mean active anterior elevation (AAE) was 160 degrees . All fractures but one healed; in one case, we had a deep infection after 80 days since the operation, treated with a preformed cement spacer.