How is this shower fitting attached?

[Paul C]

Hi Moved into house recently. Shower bracket fitting is round flat stainless steel about 2ins diameter with a ball & socket joint with a "U" shaped holder for the shower head (from a mixer tap). There are tiles with a hole cut in for the bracket, however the bracket moves/rotates in the hole against the grout/plaster? How is this actually attached?, when I rotate it it feels as though there is a rod moving around against the wall behind the tiles. Rotating the bracket does not seem to unscrew it. I've looked online and have found very similar brackets but none of them show how they are attached to the Wall through the tiles.

Thanks

SS

[Ed Sirett]

Unscrew the ball and socket joint (tricky because the part nearer the wall is hard to get a grip on). Remove the ball and other gubbins (spring and/or washers) to reveal the head of a which goes into the wall (and has become loose).