Untreated acetabular dysplasia of the hip in the Navajo - A 34 year case series followup

Patients born in the Many Farms District of the Navajo Indian Reservation f rom 1955 to 1961 were studied. Five hundred forty-eight of the 628 infants born (87%) received clinical examinations and pelvic radiographs at some ti me during the first 4 years of their lives. Eighteen (3.3%) of the 548 infa nts examined had acetabular dysplasia, Because of traditional cultural beli efs, none of these children received medical treatment, Followup evaluation s and radiographs were obtained in these 18 patients during early adolescen ce. In 10 of the original 18 patients followup evaluations and radiographs were obtained at an average age of 35 years, None of the dysplastic hips pr ogressed to frank dislocation, The mean center edge angle improved from 7 d egrees when the patients were 1 year of age, to 29 degrees when the patient s were 12 years of age, to 30 degrees when the patients: were 35 years of a ge. Despite overall improvement of hip measurements with maturity, eight hi ps in five of the 10 patients who were in their fourth decade of life and w ho were available for examination, had radiographic evidence of residual ab normalities. The hips in patients with subluxation during infancy were less Likely to be normal as adults, The results of this 34-year followup study of untreated developmental hip dysplasia showed marked radiographic improve ment in all patients during childhood; however, subtle abnormalities persis ted in the radiographs of 40% of the hips.