3D-CT分析发育性髋关节脱位骨盆形态学畸形

A 3D-CT analysis of pelvic morphologic deformity in developmental dislocation of the hip

[目的]使用3D-CT技术对单髋脱位DDH患儿的骨盆形态学畸形进行分析,按照脱位程度分型分层后对骨盆内旋畸形进行观察测量,并探讨其临床意义。[方法]回顾性收集单髋脱位DDH患儿72例,其中男12例,女60例;年龄7~60个月,平均18个月。左髋38例,右髋34例。脱位程度:Ⅰ度18例,Ⅱ度38例,Ⅲ度16例。28例正常对照组。所有患儿均行双侧髋关节CT扫描,扫描图像行三维图像重建,测量髋臼前倾角(AA)、上骨盆旋转角(URA)、下骨盆旋转角(LRA)。[结果]28例正常对照组左侧髋和右侧髋的URA、LRA和AA差异均无统计学意义(P>0.05)。72例单髋脱位DDH患儿脱位侧髋的URA、LRA和AA均大于未受累侧髋,差异有统计学意义(P<0.05)。Ⅰ度和Ⅲ度脱位组,脱位侧髋的LRA均大于未受累侧髋,且差异有统计学意义(P<0.05),但脱位侧髋的URA与未受累侧髋的URA差异并无统计学意义(P>0.05)。在Ⅱ度脱位组,脱位侧髋的URA和LRA均大于未受累侧髋,差异有统计学意义(P<0.05)。Ⅰ度、Ⅱ度和Ⅲ度脱位组,脱位侧髋的AA均与LRA成正相关。[结论]DDH患儿在矫正髋臼过度前倾时,要同时测量髋臼前倾角和下骨盆旋转角,并观察髋臼前后壁的发育情况。明确髋臼在水平面出现过度前倾的原因后再给予适当矫正,这对于预防术后髋臼后倾的发生十分重要。

[Objective] To analyze the pelvic morphologic deformity of the unilateral developmental dislocation( DDH) by using 3D- CT technology,and to explore its clinical significance after measuring the pelvic rotation deformity according to the grade of dislocation. [Methods] Seventy- two patients with unilateral DDH,including 12 male and 60 female,were recruited in this study. These patients aged from 7 to 60 months( average 18 months). Thiry- eight cases were left hip dislocation,34 cases were right hip dislocation. The dislocation grades were grade Ⅰ in 18 cases,grade Ⅱ in 38 and grade Ⅲ in 16. Another 28 patients served as the normal control group. All patients received computed tomography with bilateral hip,then the images of three- dimensional computed tomography( 3D- CT) were retrospectively reconstructed to compare the acetabular anteversion angle( AA),the rotational angle of the upper pelvis( URA),and the rotational angle of the lower pelvis( LRA). [Results]In the normal control group,the differences of URA,LRA and AA had no statistical significances( P > 0. 05). While in the unilateral DDH group,the URA,LRA and AA of the dislocated side were greater than those of intact side,showing statistically significant difference( P < 0. 05). In the group of grade I and Ⅲ,the LRA in the dislocated side were greater than that of the intact hips,and the difference was statistically significant( P < 0. 05),but the URA did not differ between the two sides( P >0. 05). In the group of grade Ⅱ,the URA and LRA in the dislocated side were greater than those of the intact side,the difference was statistically significant( P < 0. 05). There was positive correlation between AA and LRA on the dislocated side in the group of grade Ⅰ,Ⅱ,Ⅲ. [Conclusion] The pelvic rotation deformity on the dislocated side is not universally presented in unilateral DDH, and with different grades of femoral head dislocation,the mechanism of pelvic rotation deformity may not be consistent. Not only the acetabular anteversion angle,but also the rotational angle of the upper pelvis are needed for measurement,and the development situation of the acetabulum anterior wall and posterior wall should be observed as well. After clear determination of excessived acetabular anteversion,we could give appropriate correction,as well as prevent acetabular retroversion postoperatively.