Duchenne's muscular dystrophy (DMD), characterized by gradually developing muscular weakness, leads to respiratory symptoms and reduced lung function. We aimed to assess lung function in 25 patients with DMD in relationship to age and muscular function. The 25 boys, mean age 13 years, comprized patients in southern Norway with DMD, taking part in an epidemiological follow-up study. None had chronic respiratory disease. Lung function was measured by maximum expiratory flow-volume loops and whole body plethysmography, and repeated after 1 year (n= 14). Lung function was reduced compared to predicted values for healthy children. Forced expiratory volume in 1 sec (FEV1)% predicted and forced vital capacity (FVC)% predicted correlated (significantly) inversely to age. FEV1 and FVC decreased annually 5.61 and 4.2% of predicted, respectively. Absolute values of FVC (litres) and FEV1 (1 sec(-1)) increased until mean age 14 years, decreasing thereafter. Values in % predicted decreased steadily throughout the age range (6-19 years). Lung function correlated closely to upper limb muscle function.

Results-Tidal expiratory volume (V E )and compliance of the respiratory system (CRS) tended to be higher in the sitting compared to the supine position, but this was not statistically significant. However, applying bracing in the sitting position significantly reduced V E . The highest values of CRS and V E were found in the sitting position without bracing. Conclusion-Impairment of tidal respiration must be considered when applying spinal bracing in very young children developing scoliosis with SMA. (Arch Dis Child 2001;84:521-524)

The prevalence of child neuromuscular disease in Southern Norway by January 1st, 1983, was studied by collecting data from all available sources. All children born 1.1. 1965 or later were included in the study. The total group consisted of 110 patients from 17 different diagnostic categories. Total prevalence on this group was found to be 24.9 times 105. Duchenne muscular dystrophy (DMD), with a prevalence of 10.89 times 105 constituted 29.2% of the total material. In the spinal muscle atrophy group (SMA), we found a significant increase in the number of boys affected, although an autosomal recessive mode of inheritance was found likely in all probands. Prevalence figures of child neuromuscular disease are hard to compare, as most studies deal with an adult population. The prevalences of common and well‐known large categories of neuromuscular diseases in childhood are in agreement with previous studies. For less well known and mild diseases, our figures are low. This may be due in part to a later onset and in part to a health system not sensitive to parents' complaints.

In a survey carried out to determine the incidence of Duchenne muscular dystrophy in South East Norway, 38 cases were ascertained among 149,975 live male births during the years 1968-1978. The overall incidence is 1:3,917 in live male births (25.33 x 10(-5). This incidence is compared with those in other studies. There is an apparent drop in incidence in the last cohort studied, and the possible role of genetic counselling and antenatal sexing are discussed.

The orofaciodigital syndromes are a group of possibly seven different malformation syndromes including oral, facial, and digital malformations. Type I has X linked dominant inheritance whereas the other types show autosomal recessive inheritance. An exact diagnosis is therefore important for genetic counselling. We here report a girl with orofaciodigital syndrome type I. She had cystic kidney disease at the age of 8 months which has not previously been reported in an infant with orofaciodigital syndrome. In addition she had unilateral tibial pseudarthrosis which has only rarely been reported in the orofaciodigital syndromes and in type II only.