Value of physical examination in the diagnosis of developmental hip dislocation in preterm infants

Abstract

Background: Developmental dislocation of the hip joint is among joint abnormalities and lack of its early diagnosis leads to irreversible complications and disabilities. Methods: The current cross sectional study was conducted on 210 eighteen - month - old premature infants. Premature infants at term gestational age were examined by a neonatologist and underwent a sonographic scanning by a skilled radiologist. The results of the physical examination and ultrasound reports were collected and analyzed. Results: In the clinical assessment, hip joint examination was diagnosed abnormal in 22 cases (10.4%) and joint dislocation was diagnosed by ultrasonographic examination in 17 patients (8.1%). In one high - risk case, despite normal clinical examination (0.48%), the dislocation was diagnosed by ultrasonographic evaluation. There was a significant relationship between hip dislocation rate, and reduced mean gestational age and birth weight (P < 0.05). The dislocation prevalence in the twins was significantly more than that of other infants (P = 0.001). In the current study, there was no statistically significant relationship between gender, family history, oligohydramnios, presentation, and type of delivery with joint dislocation (P > 0.05). In diagnosis of joint dislocation, clinical examination (the results of the Ortolani and the Barlow tests) had sensitivity of 94% and specificity of 97% compared with sonography; the positive and negative predictive values were 73% and 99%, respectively. Conclusions: Clinical examination has high sensitivity and specificity for early diagnosis of developmental hip dislocation. If there are risk factors, ultrasonographic scanning is recommended despite normal physical examination, and ultrasound is not necessary in case of normal physical examination and the absence of risk factors.