Iwai Shintaro, Kabata Tamon, Maeda Toru, Kajino Yoshitomo, Watanabe Shin, Kuroda Kazunari, Fujita Kenji, Hasegawa Kazuhiro, Tsuchiya Hiroyuki
Department of Orthopaedic Surgery, Kanazawa University Graduate School of Medical Science, 13-1 Takara-machi, Kanazawa, 920-8641, Japan.
J Orthop Sci. 2014 May;19(3):443-50. doi: 10.1007/s00776-014-0547-x. Epub 2014 Feb 18.
Some reports indicate that one of major causes of clinical failure after periacetabular osteotomy is development of secondary femoroacetabular impingement (FAI). To assess the impact of range of motion (ROM) on the increase in FAI following rotational acetabular osteotomy (RAO), we performed FAI simulations before and after RAO.
We evaluated 12 hips that had undergone RAO (study group), and 12 normal hips (control group). The study group was evaluated before and after surgery. Morphological parameters were evaluated to assess acetabular coverage. The acetabular anteversion angle, anterior CE angle, alpha angle, and combined anteversion angle were also measured. Impingement simulations were performed using 3D-CT. The ROM which causes bone-to-bone impingement was evaluated in flexion (flex), abduction, external rotation at 0° flexion, and internal rotation at 90° flexion. The lesions caused by impingement were evaluated.
Radiographic measurements indicated improved postoperative acetabular coverage in the study group. The crossover sign was recognized pre- and postoperatively in every case in the study group and in no cases in the control group. In the simulation study, flexion, abduction, and internal rotation at 90° flexion decreased postoperatively. Impingement occurred within 45° internal rotation at 90° flexion in two preoperative and nine postoperative cases. The impingement lesions were anterosuperior of the acetabulum in all cases. There were correlations between anterior CE angle, CE angle, acetabular anteversion angle, and hip flexion angle. There were also correlations between the anterior CE angle, combined anteversion angle, and angle of internal rotation at 90° flexion.
In the postoperative simulation, there was a tendency to reduce the ROM in flexion, abduction, and internal rotation at 90° flexion due to impingement. Since there were more cases which caused impingement within 45° internal rotation at 90° flexion after RAO, we consider there is a potential for increased FAI after RAO.
一些报告表明，髋臼周围截骨术后临床失败的主要原因之一是继发性股骨髋臼撞击症（FAI）的发生。为了评估活动范围（ROM）对旋转髋臼截骨术（RAO）后FAI增加的影响，我们在RAO前后进行了FAI模拟。
我们评估了12例接受RAO的髋关节（研究组）和12例正常髋关节（对照组）。研究组在手术前后进行评估。评估形态学参数以评估髋臼覆盖情况。还测量了髋臼前倾角、前CE角、α角和联合前倾角。使用三维CT进行撞击模拟。评估在屈曲（flex）、外展、0°屈曲时的外旋和90°屈曲时的内旋中导致骨对骨撞击的ROM。评估由撞击引起的损伤。
影像学测量表明研究组术后髋臼覆盖情况有所改善。研究组的每个病例在术前和术后均出现交叉征，而对照组无一例出现。在模拟研究中，术后90°屈曲时的屈曲、外展和内旋减少。在术前2例和术后9例病例中，90°屈曲时内旋45°以内发生撞击。所有病例的撞击损伤均位于髋臼的前上方。前CE角、CE角、髋臼前倾角和髋关节屈曲角之间存在相关性。前CE角、联合前倾角和90°屈曲时的内旋角度之间也存在相关性。
在术后模拟中，由于撞击，90°屈曲时的屈曲、外展和内旋的ROM有减小的趋势。由于RAO后90°屈曲时内旋45°以内导致撞击的病例更多，我们认为RAO后有FAI增加的可能性。
