Park J, et al. - Researchers performed a comparison of the acetabular teardrop (the structure located inferomedially in the acetabulum, just superior to the obturator foramen; the medial lip is the interior, and the lateral lip is the exterior of the acetabular wall) with the inferior acetabular rim as anatomical landmarks to measure the acetabular abduction angle (AAD) using coronal CT images from five different levels[AAD (+ 10) (10 mm anterior to the femoral head center), AAD (+ 5) (5 mm anterior to the femoral head center), AAD (0) (through the femoral head center), AAD (− 5) (5 mm posterior to the femoral head center), and AAD (− 10) (10 mm posterior to the femoral head center)]. In this retrospective study, they assessed 120 pelvic CT scans from 60 females (mean age of 48 years) and 60 males (mean age of 46 years) with non-orthopedic pathologies or stress fractures of the proximal femur. Division of the measurements into two groups was then performed: teardrop-based AADs [AAD (+ 10), AAD (+ 5), and AAD (0)] and rim-based AADs [AAD (− 5) and AAD (− 10)]. The groups did not have any mean significant differences in AAD but had significant difference. Relative to considering the acetabular teardrop, considering the inferior acetabular rim for AAD measurements can be more accurate as the inferior rim represents the nearly hemispheric acetabulum better than does the teardrop. To avoid confusion regarding acetabular abduction, they recommend differentiating between the teardrop and the inferior acetabular rim when measuring AAD.