Complications can occur with any type of surgery. Implant failure due to fracture (breakage of the bone or the implant), loosening of the implant, or subsidence (sinking into the bone) are the most common problems with shoulder joint replacements.
Other problems that can occur include subluxation (partial dislocation), polyethylene wear, and periprosthetic lucency (thinning of the bone around the implant). Subluxation comes with decreased and painful motion. There are no such symptoms with bone changes (erosion or lucency).
In a recent study comparing metal-backed to nonmetal-backed and metal-backed compared to all-polyethylene (plastic) components, there were no differences in results based on gender (male versus female). Although both the men in your family have had a failed result, this does not mean it was because of their gender.
It could be related to the similarities in their anatomy (which you may share). Or it could be the type of implant they received. Sometimes bone loss is significant enough to make a difference. In some cases, it may be related to the surgery itself.
When you see your surgeon, you might want to alert him or her to your family history and the results of your siblings. The surgeon will take a personal and family history, examine you, and order appropriate tests. He or she will be able to advise you from the results of those tests.