Daniel Klein, 51, is charged with abuse of a care-dependent person and reckless endangerment, township police said.
Authorities were called to Klein's Dresner Circle home by neighbors who noticed packages piling up by the door.
Arriving officers could see "a large amount of trash on the floor" and "numerous flies present on the windows," the department said in a release.
They forced entry and spoke with Klein who led them to his mother's room, where police said she was "covered in dried feces and maggots" and had "ram's horn toenails."
Responding EMTs said she was "fused to the bed" and took her to Crozer Chester Medical Center, the release says.
Klein was also taken to the hospital and then arrested, according to police. He was unable to post 10 percent of his $50,000 bail and taken to the George Hill Correctional Facility, authorities said.
He has a preliminary hearing scheduled for April 25.
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