Impact of unilateral periacetabular osteotomy on bony birth canal in female hip dysplasia patients with gynecoid and anthropoid type pelvis: a pelvic three-dimensional computed tomography measurement using maximum- inscribed-sphere method

Unilateral PAO did not affect the narrowest part of the bony birth canal in either pelvis type but caused mild narrowing above the ischial spine, with notable effects in the anthropoid group. In gynecoid pelvis patients, it led to narrowing through changes in the relation between the femoral head and Kohler's line.