The assumed cause of muscle hypertrophy in KDSS is an abnormal metabolism of carbohydrates leading to increased glycogen accumulation and increased mucopolysaccharide deposits in the muscles. Yet another speculation is an excess intra cellular calcium due to ineffective reuptake into the sarcoplasmic reticulum, which causes a sustained contraction and thereby hypertrophy. In hypothyroidism the fast twitch muscle fiber is converted to slow twitch fiber, causing the slower reflex or hung up reflex. This may occur as a result of reduction in muscle mitochondrial oxidative capacity and beta-adrenergic receptors, as well as the induction of an insulin-resistant state, due to<unk> ase in thyroid hormones. The causes for muscle weakness is said to be<unk> ase in muscle carnitine,<unk> ased muscle oxidation, expression of a slower ATPase in myosin chain and<unk> ased transport across the cell membrane. The rigidity associated with congenital hypothyroidism may be due to abnormal development of basal ganglia.
Kocher–Debre–Semelaigne syndrome
Omenn syndrome
Wolcott–Rallison syndrome
Kapur–Toriello syndrome
Ellis–Van Creveld syndrome
Malouf syndrome
Young–Madders syndrome
Wilson–Turner syndrome