PURPOSE: To obtain a series of parameters describing the shape and bone thickness of the fixation route along the superior border of the arcuate line, so as to provide references for pelvic and acetabular surgery and design pelvic anatomic internal fixators. METHOD: A total of 175 complete pelvic computed tomography (CT) scans of normal adult pelvises were collected. Each person's CT scans were reconstructed to create a three-dimensional pelvic model. A curve of the fixation route was delineated and divided into 11 equal parts. The total length of the curve, the radius of curvature, and the bone thickness at each decile point were all measured. The position of the pelvic inlet, the anterior and posterior sagittal diameter were measured. RESULTS: The radius of curvature at each decile point were 29.18 ± 15.53, 55.27 ± 29.48, 43.04 ± 14.42, 59.62 ± 21.02, 91.67 ± 52.01, 78.9 ± 38.66, 75.76 ± 25.87, 61.75 ± 16.68, 54.62 ± 14.88, and 43.61 ± 19.10 mm, respectively. The anterior and posterior sagittal diameter of the pelvic inlet was 66.01 ± 9.15 and 41.36 ± 8.19 mm, respectively. For all groups divided by the ratio of the posterior and the anterior sagittal diameter, the decile points 1, 3, and 10 had smaller radii of curvature than the before and after points, respectively. CONCLUSIONS: The curve of the fixation route along superior border of arcuate line has a relatively greater bending degree at the pubic tubercle, iliopubic eminence and close to the sacroiliac joint. With the transition of the pelvic inlet shape from android to gynecoid and platypelloid type, the bone surface at the iliopubic eminence becomes flatter. Pelvic and acetabular surgery could be more accurate by referring to the previous key bending points and the change of the pelvic inlet shape.
PURPOSE: To obtain a series of parameters describing the shape and bone thickness of the fixation route along the superior border of the arcuate line, so as to provide references for pelvic and acetabular surgery and design pelvic anatomic internal fixators. METHOD: A total of 175 complete pelvic computed tomography (CT) scans of normal adult pelvises were collected. Each person's CT scans were reconstructed to create a three-dimensional pelvic model. A curve of the fixation route was delineated and divided into 11 equal parts. The total length of the curve, the radius of curvature, and the bone thickness at each decile point were all measured. The position of the pelvic inlet, the anterior and posterior sagittal diameter were measured. RESULTS: The radius of curvature at each decile point were 29.18 ± 15.53, 55.27 ± 29.48, 43.04 ± 14.42, 59.62 ± 21.02, 91.67 ± 52.01, 78.9 ± 38.66, 75.76 ± 25.87, 61.75 ± 16.68, 54.62 ± 14.88, and 43.61 ± 19.10 mm, respectively. The anterior and posterior sagittal diameter of the pelvic inlet was 66.01 ± 9.15 and 41.36 ± 8.19 mm, respectively. For all groups divided by the ratio of the posterior and the anterior sagittal diameter, the decile points 1, 3, and 10 had smaller radii of curvature than the before and after points, respectively. CONCLUSIONS: The curve of the fixation route along superior border of arcuate line has a relatively greater bending degree at the pubic tubercle, iliopubic eminence and close to the sacroiliac joint. With the transition of the pelvic inlet shape from android to gynecoid and platypelloid type, the bone surface at the iliopubic eminence becomes flatter. Pelvic and acetabular surgery could be more accurate by referring to the previous key bending points and the change of the pelvic inlet shape.
Authors: Wang Xian-quan; Cai Jin-fang; Cao Xue-cheng; Mu Wei-dong; Zhang Wei; Sun Shui; Zhang Jin-lu; Wang Jian; Li Wei Journal: Arch Orthop Trauma Surg Date: 2010-02 Impact factor: 3.067