Musculoskeletal manifestations in hyperlipidaemia: a controlled study.

Eighty eight patients with hyperlipidaemia (81 white patients from South Africa and seven patients of mixed race from the West Cape area) were studied. Forty eight had adult familial hypercholesterolaemia, 16 had juvenile familial hypercholesterolaemia, and 24 had mixed hyperlipidaemia (increased cholesterol and triglycerides). They were interviewed and examined and their musculoskeletal manifestations compared with 88 controls with normal lipid profiles, and matched for age, sex, and race for each group of patients. The following manifestations were significantly increased in the patients: (a) tendon xanthomas particularly of the tendo Achillis in patients with adult familial hypercholesterolaemia and mixed hyperlipidaemia; (b) tendo Achillis tendinitis in patients with adult familial hypercholesterolaemia and mixed hyperlipidaemia; and (c) oligoarthritis in patients with mixed hyperlipidaemia but not in those with adult familial hypercholesterolaemia. Migratory polyarthritis and transient tendo Achillis pain were rare. Thirty eight per cent of patients with juvenile familial hypercholesterolaemia had musculoskeletal system manifestations none of which was significantly increased compared with controls. There was a significant association between tendon xanthomas and tendo Achillis tendinitis. There was a significant difference in pretreatment cholesterol levels in the patients with adult familial hypercholesterolaemia and musculoskeletal system manifestations compared with those without and in all three groups combined. The study confirms an association between hyperlipidaemia and tendon xanthomas, tendo Achillis tendinitis, and to a lesser extent oligoarthritis but not migratory polyarthritis or transient tendo Achillis pain as reported in other studies. It also shows that musculoskeletal system manifestations antedated the diagnosis of hyperlipidaemia in 24/39 (62%) patients and that the manifestations improved or resolved completely in 19/30 (63%) patients after receiving lipid lowering treatment. It is therefore important to recognise the association between musculoskeletal system manifestations and hyperlipidaemia for diagnostic and therapeutic reasons.