Days of lying on a sickbed continued.
Rare kanji spelling; 蓐 is an uncommon character meaning 'straw mat' or 'bedding'.
Variant spelling using 褥 (mattress, bedding); also rare.
Compound of 病 (illness) and 蓐/褥 (straw mat, bedding). The exact historical derivation is uncertain; the spelling is conventionally associated with the meaning 'sickbed'.