Incidence of Legg-Calve-Perthe's Disease in the Faroe Islands

Abstract

The object of the present study was to find the incidence of LCPD and capital dysplasia in the population of The Faroe Islands, the incidence of familial cases cf the disease, and finally to describe the characteristical radiological changes of the disease in the various age groups.

It is seen that 50 % of the patients were younger than 5 years when the disease was diagnosed. Cases of capital dysplasia were dominant in the youngest age groupe, 7 of the 9 patients with capital dysplasia being less than 3 years old, while only one patient with LCPD and one patient in an intermediate state were less than 3 years old at the time of diagnosis. Cases of typical LPCD were dominant in patients aged between 5 and 9 years, some intermediate cases being found in the youngest, while patients who were more than 6 years old had exclusively LCPD, with the most severe cases in the oldest.

Finally only 2 patients were more than 9 years old at the time of diagnosis, and osteochondritis dissecans was diagnosed in both cases. It seems to appear from the radiological changes that growth disorders may be dominant in the youngest patients, while the typical aseptic necroses are dominant in the age group between 5 and 9 years, in accordance with the nature of the blood supply to the capital epiphysis in this age group as described by Trueta (1957) and others. 

It was found that bilateral cases were more frequent in patients with dysplasia than in patients with LCPD. Bone age was most frequently delayed in patients with capital dysplasia. The incidence of LCPD was found to be more than twice as high in the
Faroe Islands compared with Denmark, and the familial cases were far more frequent than found in other series. Osteochondroses with other sites were also found in the families. These findings point to the possibility of capital dysplasia as being expressive of a hereditary primary growth disturbance, with delayed and irregular growth of epiphysis of the femoral head, which, in its turn, may be a disposing factor in the development of LCPD.