Volume-based dysplasia severity index with the spheric cup method in the evaluation of adult and adolescent acetabular dysplasia

Abstract

Introduction / Aim: Defining and treating adult and adolescent acetabular dysplasia before arthrosis develops is one of the basic principles of hip-preserving surgery. During the evaluation of cases with asymptomatic or mild symptoms, the severity of the acetabular covering deficiency directs the treatment. We attempted to find answers to two questions with our study: 1) Are the values revealed by the described measurement technique sufficient to detect acetabular dysplasia? 2) Do the criteria calculated by the current technique correlate with the well-known radiological criteria for acetabular dysplasia? Material and Method: Eighteen hips of patients who had undergone periacetabular osteotomy evaluated by computed tomography (CT) between June 2009 and February 2019 were included in the study (Group 1, dysplasia group). Eighteen patients of similar age and sex, who had tomography examination from the pelvic region, except for orthopedic reasons, were identified between the same dates (Group 2, control group). In the tomography examinations of the patients, the entrance area of the acetabulum was determined using the multiplanar reformation (MPR) technique. Acetabulum volume and femoral head volume was calculated according to the spheric cup measurement method. Acetabular index (AI), extrusion index (EI), Sharp angle (SA), lateral center edge angle (LCEA), and anterior center edge angle (ACEA) values were calculated from direct graphy and CT scanograms of the patients. Findings / Results: In the comparative analysis between the groups, a significant difference was observed in terms of acetabular volume, VBADSI, AI, EI, LCEA, SA, and ACEA values (p