Muscular pseudohypertrophy - hypothyroidism, also known as Kocher-Debre-Semelaigne syndrome is a rare disorder characterized by pseudohypertrophy of muscles due to longstanding hypothyroidism. The disease is Monarch Disease Ontology id MONDO_0016521 (muscular pseudohypertrophy-hypothyroidism syndrome). Also known as: Kocher-Debre-Semelaigne syndrome, Kocher-Debré-Semelaigne syndrome.