pacemaker side effects

My mother in law had a pacemaker installed in May of 2007.  Since then she has had some problems with extreme pain in different parts of her body.  One week she had a large lump on her left hand and arm.  The following week she had a lump on her left hip.  The lumps go away after a few days, but then reappear in other locations.  She has had these pains in her neck, arms, hands, shoulders, hips, and legs.  If anyone has any ideas or information please let me know.  We have been to many doctors and surgeons, but we have gotten no answers as to her condition.  Any help would be greatly appreciated.

[Cleveland Clinic]

She should have an echocardiogram done to make sure that there is no infection of the pacemaker wire in her heart, a condition known as endocarditis.  It can present with painful lumps.  I am not sure where her pain is coming from.  One thing to consider is whether this is some sort of rhematologic condition.  Maybe she should see a rheumatologist to further assess this.