LEGG-CALVE-PERTHES DISEASE IN GIRLS - A COMPARISON OF THE RESULTS WITH THOSE SEEN IN BOYS

We reviewed the records and roentgenograms of all patients with Legg-C alve-Perthes disease who had been seen at our institution between 1940 and 1996, One hundred and five girls (122 hips) and 470 bogs (531 hip s) were identified, Thus, 18 per cent of the 575 patients in the prese nt series were girls. Seventeen (16 per cent) of the girls and sixty-o ne (13 per cent) of the boys had bilateral involvement, Although more girls than boys had severe involvement of the femoral head and the lat eral pillar, we could not detect a significant difference between the two groups with respect to the distribution of the involvement of the hips according to the system of Catterall or the lateral pillar classi fication (p > 0.05, beta = 0.99). Serial roentgenograms that showed al l four stages of the disease according to the system of Waldenstrom we re available for fifty-two hips in girls and 184 hips in boys. A revie w of these roentgenograms revealed that the average ages of the girls at the stages of necrosis, fragmentation, reossification, and remodeli ng were 6.8, 7.3, 7.9, and 9.5 years, respectively, whereas the averag e ages of the boys were 6.8, 7.3, 7.9, and 9.9 years, respectively, Gi rls, however, had closure of the affected proximal femoral physis at a n average age of 12.9 years, whereas boys had closure at an average ag e of 15.8 years. Therefore, girls had a shorter potential period for r emodeling of the femoral head (average, 3.4 years) compared with boys (average, 5.9 years), Sixty-four girls (seventy-eight hips) and 363 bo ys (416 hips) had reached skeletal maturity by the time of the latest follow-up and were evaluated according to the system of Stulberg et al ,; we could not detect a significant difference between boys and girls with respect to the distribution of the hips according to this system (p > 0.05, beta = 0.99), Although the numbers were too small for stat istical analysis, our findings suggest that boys and girls who have th e same Catterall or lateral pillar classification at the time of the i nitial evaluation fan be expected to have similar outcomes according t o the classification system of Stulberg et al.