摘要目的:探讨采用三维CT最大内切球法分析单侧髋臼周围截骨术（periacetabular osteotomy，PAO）对女性髋关节发育不良（developmental dysplasia of the hip，DDH）患者骨产道影响的可行性。方法:选取62例行单侧PAO手术的育龄女性DDH患者，采集手术前后骨盆CT的"DICOM"数据，用最大内切球法在医学影像交互软件（the medical imaging interaction toolkit，MITK）上测量25层骨产道的大小（即最大内切球直径）。于手术前后骨盆站立正位X线片上测量外侧中心边缘（lateral center edge，LCE）角、髋臼倾斜角（T?nnis角）和髂坐线与股骨头内缘的距离。根据LCE角大小将患者分为严重组（LCE≤0°）和非严重组（0°<LCE<20°）。结果:PAO术后坐骨棘以上（1~20层）骨产道变窄，手术前后最大内切球直径的差异有统计学意义（ P<0.05），差值的均值范围为0.86~5.95 mm；坐骨棘以下（21~25层）手术前后最大内切球直径的差异无统计学意义（ P>0.05）。其中髋臼截骨块前上缘（1~13层）变窄明显（手术前后差值的均值范围为4.23~5.95 mm）；髋臼截骨块前缘耻骨支下缘与闭孔后缘上部之间的区域（5~10层）变窄最多（5.62~5.95 mm）。手术前后骨产道最窄位置均在坐骨棘平面（20层），术前最大内切球直径为（105.34±7.16）mm，术后为（104.47±7.06）mm，差异有统计学意义（ t=2.198， P=0.032）。髋关节旋转中心内移与1~20层骨产道变窄呈正相关，T?nnis角变小与1~10层骨产道变窄呈正相关，LCE增大与2~5层骨产道变窄呈负相关（ P<0.05）。髂坐线与股骨头内缘的距离对1~20层骨产道大小的影响有统计学意义（ β=0.27~0.50， P<0.05）。身高与术前、术后骨产道最窄部位的大小呈正相关（ r=0.565， r=0.586， P<0.001）。严重组与非严重组手术前后骨产道及骨产道变窄程度的差异无统计学意义（ t=-0.685~0.655， P>0.05）。 结论:单侧PAO引起坐骨棘以上骨产道变窄，轻度影响骨产道最窄位置（坐骨棘水平）。单侧PAO不会影响骨产道正常的DDH育龄女性患者正常胎儿的正常分娩。

abstractsObjective:To investigate the influence of unilateral periacetabular osteotomy (PAO) on the bony birth canal (BBC) in female patients with developmental dysplasia of the hip (DDH) by using pelvic 3D-CT maximum-inscribed-sphere (MIS) method.Methods:A total of 62 female DDH patients of childbearing age were included in the present study. The DICOM data of their pre- and post-operative pelvic CT was collected. The diameters of the MIS in 25 layers of the BBC were measured on the Medical Imaging Interaction Toolkit (MITK) platform. Lateral center edge angle (LCE), T?nnis angle and the distance between the medial margin of the femoral head and Kohler's line were measured on standing anteroposterior pelvic radiographs before and after unilateral PAO. Patients were divided into severe (LCE≤0°) and non-severe group (0°<LCE<20°) according to their LCE values.Results:After unilateral PAO, the BBC above the sciatic spine (1-20th layer) narrowed (0.86-5.95 mm, P<0.05). However, there was no change in levels below the sciatic spine (21-25th layer, P>0.05). The anterior margin of acetabular fragment (1-13th layer) narrowed significantly (4.23-5.95 mm) after unilateral PAO with the narrowest part (5.62-5.95 mm) locating at the inferior margin of pubic ramus and the region superior to the lateral margin of obturator foramen (5-10th layer). The narrowest part of BBC before and after the surgery occurred at the level of bilateral sciatic spines (20th layer). The diameter of MIS changed significantly from 105.34±7.16 mm pre-operatively to 104.47±7.06 mm post-operatively ( t=2.198, P=0.032). There was a positive correlation between the inward displacement of the hip center and the narrowing of the 1-20th layer of the BBC. The decrease of T?nnis angle was positively correlated with the narrowing of the 1-10th layer of the BBC. The increase of LCE was negatively correlated with the narrowing of 2-5th layer of the BBC ( P<0.05). The standardized coefficients were with statistical significance when comparing the distance between the Kohler's line and the medial margin of the femoral head to the size of the 1-20th layer of the BBC ( β=0.27-0.50, P<0.05). The height was positively correlated with the size of the narrowest part of the BBC before and after the surgery ( r=0.565, r=0.586, P<0.001). There was no difference between severe group and non-severe group in their extent of BBC narrowing before and after surgery ( t=-0.685-0.655, P>0.05). Conclusion:Unilateral PAO results in mild narrowing of the BBC superior to the sciatic spine. The narrowest part of the BBC is located at the sciatic spine. Unilateral PAO has slight effects on the narrowest position of the BBC. Normal delivery of a healthy fetus in female patients with DDH of childbearing age could not be affected by unilateral PAO in normal BBC settings.