3D Characterization of Acetabular Deficiency in Children with Developmental Dysplasia of the Hip

Abstract

Background The purpose of this study is to determine if a quantitative method can be used to identify differences in 3D morphology between normal and developmentally dysplastic hips and to identify specific areas of undercoverage in children with DDH compared to age- and sex-matched controls. Methods Subjects were included if they were typically developing children with no other underlying conditions affecting their musculoskeletal system and had an available pelvic CT scan (67 hips). Custom software was used to measure standard variables defining acetabular morphology (version, tilt, surface area). Acetabuli were divided into equal octants; coverage angles were measured for each octant of interest. Variables were compared with age- and sex-matched controls (128 hips) using analysis of variance or the Mann–Whitney test. Results Hips with DDH were more anteverted compared to normal hips (DDH: 22.6˚, Control: 16.4˚, p < 0.001). The surface area was similar between groups. 28% of hips had a global deficiency, 24% were anteriorly deficient, 19% were laterally deficient, 10% were anteverted (under covered anteriorly and over covered posteriorly), 3% were posteriorly deficient, and 15% of hips had borderline undercoverage. None of the hips in this cohort were found to be retroverted. Conclusions This is the first study to quantify the 3D acetabular deficiency in children with DDH compared to age- and sex-matched controls. We found wide variability in coverage patterns among dysplastic hips. It is imperative to define the specific acetabular deficiency for each individual patient prior to surgical correction. Level of evidence III – Case–control study.

The Anterior Modified San Diego Acetabuloplasty Does Not Increase Superior-Anterior Coverage in Patient-Specific 3D-Printed Models

“…Understanding the morphology of the dysplastic acetabulum before surgical intervention is important for successful treatment, and 3D CT scans and models are great tools to help surgeons precisely identify deficiencies within the acetabulum 19–21 . In addition, 3D modeling is a powerful tool that can be used to comparatively study the changes after different pelvic osteotomies 14,15 and the current study further demonstrates this utility.…”

Comparison of Acetabular Morphology Changes After Pediatric Pelvic Osteotomies Using Patient-Specific 3-D Models

“…Patient-specific 3-D print technology provides a unique opportunity to quantitatively compare the acetabular volume and shape changes between four commonly performed pediatric pelvic osteotomies for acetabular dysplasia 22 (Figure 3). Unique material properties and technologies allowed for the printing of patient-specific skeletally immature pelvis models that could be imaged and operated on similar to a pediatric pelvis.…”

Hip and Happening: Current Concepts in the Diagnosis and Management of Developmental Dysplasia of the Hip in 2022

“…Baghdadi & Sankar [22] reviewed the literature regarding the current evidence and controversies surrounding this important topic, especially in relation to the incidence and risk factors for RAD, the diagnostic work-up, indications for treatment, and the ideal age and procedure of choice in the management of RAD. Badrinath et al [23] quantified the 3D acetabular morphology in children with DDH compared to age-and sex-matched controls using pelvic CT scans and a custom 3D image processing software, and found a wide variability in acetabular coverage patterns in dysplastic hips, while Patwardhan et al [24] evaluated acetabular development in late-diagnosed DDH treated by open reduction at a mean age of 2 years with or without a concomitant femoral osteotomy. Tolk et al analysed the development of leg length discrepancy (LLD) and its influence on persistent acetabular dysplasia in children with DDH [25].…”