A man in his 80s who has Alzheimer's was padlocked into a onesie by his partner, a judge has heard.
The woman, in her 50s, "fashioned" the all-in-one suit so a padlock could be used to stop it being unzipped, Judge Denzil Lush was told.
Detail emerged in a ruling by the judge after a hearing in London at the Court of Protection, where issues relating to sick and vulnerable people are analysed.
Social workers had raised the concerns.
An official from the Office of the Public Guardian - which protects and helps people who do not have the mental capacity to make decisions - told the judge about the onesie.
She said the approach adopted by the woman was "certainly unusual" and had been a "cause of concern for local authority services".
Judge Lush had been asked to analyse a legal issue relating to the man's son, who had been given authority to manage his father's financial affairs.
He made no criticism of the woman in his ruling. He said she dressed the man, who lived at his home with the woman, in the onesie "on medical advice".