Reliability of radiographic measurements for hip dysplasia using a reduced radiation technique

The purpose of this study was to examine whether measurement accuracy is impacted with a low radiation radiograph technique. Treatment decisions for hip dysplasia require serial radiographs to monitor acetabular anatomy. However, radiation use creates concern for future malignancy. Standard radiograph technique utilizes a grid to enhance clarity, but requires a larger X-ray dose. We hypothesized grid removal would lower radiation exposure without decreasing measurement accuracy. This is a retrospective cohort study of patients with idiopathic DDH and neuromuscular hip displacement at a single institution from 2019 to 2020 receiving surveillance radiographs. A cohort receiving modified technique radiographs (grid removed) was compared to an age-matched cohort receiving standard technique radiographs. Four examiners measured radiographs on two separate occasions, a minimum of 2 weeks apart. Migration percentage (MP) was measured for neuromuscular patients and acetabular index (AI) for idiopathic DDH. Intraclass correlation coefficient (ICC) with a 95% confidence interval (CI) was used to evaluate inter-observer and intra-observer agreement for measurements. Average radiation dose for both techniques. A total of 134 age-matched patients were included for measurement of MP. Thirty age-matched patients were included for AI measurements. Inter and intra-rater reliability of MP and AI were not different with or without use of the grid. There was a 50–75% decrease in radiation dose...
Source: Journal of Pediatric Orthopaedics B - Category: Orthopaedics Tags: Hip Source Type: research