Kohno Yusuke, Nakashima Yasuharu, Hatano Takashi, Akiyama Mio, Fujii Masanori, Hara Daisuke, Kanazawa Masayuki, Haraguchi Akihisa, Iwamoto Yukihide
Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
J Orthop Res. 2016 Sep;34(9):1613-9. doi: 10.1002/jor.23147. Epub 2016 Jan 12.
Cam deformity could lead to suboptimal articulation by causing secondary femoroacetabular impingement after periacetabular osteotomy; however, the inherent femoral head-neck morphology in dysplastic hips and the effect of an additional osteoarthritic deformity have not been well described. We compared femoral head-neck morphology using three-dimensional imaging of normal and dysplastic hips in pre/early (Tönnis grade 0 and 1) and advanced stage osteoarthritis (Tönnis grade 2). Using computed tomography, we measured the circumferential α-angle and head-neck offset ratio in 68 dysplastic hips and 24 normal hips. Locations of the head-neck junction were represented by the clock position. In the pre/early group, the α-angle was significantly larger at the anterosuperior and inferior aspects (1, 2, and 5-7 o'clock) and head-neck offset ratio was smaller at the anterosuperior aspect (2 o'clock) than in the control group. The α-angle was significantly larger at the anterior aspects (1-4 o'clock) in the advanced group than in the pre/early group. The maximum α-angle was most commonly found at 2 o'clock (60%, 41/68 hips) in dysplastic hips. The prevalence of cam deformity (maximum α-angle >55°) was 4.2% (1/24 hips) in the control group, 22% (11/50 hips) in the pre/early group, and 50% (9/18 hips) in the advanced group. Cam deformity, inherent in the pre/early group, was found with relatively high frequency. The higher prevalence in the advanced group reflected degeneration-modified changes. When performing periacetabular osteotomy, preoperative radiographic assessments should include the femoral head-neck junction to prevent secondary femoroacetabular impingement, especially in patients with advanced stage osteoarthritis. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1613-1619, 2016.
髋臼周围截骨术后，凸轮畸形可通过引起继发性股骨髋臼撞击导致关节连接不理想；然而，发育不良髋关节中固有的股骨头-颈形态以及额外骨关节炎畸形的影响尚未得到充分描述。我们使用三维成像比较了正常髋关节和发育不良髋关节在术前/早期（Tönnis分级0级和1级）和晚期骨关节炎（Tönnis分级2级）时的股骨头-颈形态。通过计算机断层扫描，我们测量了68例发育不良髋关节和24例正常髋关节的圆周α角和头颈偏移率。头颈交界处的位置用钟面位置表示。在术前/早期组中，与对照组相比，前上和下方面（1、2和5-7点）的α角明显更大，前上方面（2点）的头颈偏移率更小。晚期组前方面（1-4点）的α角明显大于术前/早期组。发育不良髋关节中最大α角最常见于2点（60%，41/68例髋关节）。凸轮畸形（最大α角>55°）的患病率在对照组中为4.2%（1/24例髋关节），术前/早期组中为22%（11/50例髋关节），晚期组中为50%（9/18例髋关节）。术前/早期组中固有的凸轮畸形发现频率相对较高。晚期组中较高的患病率反映了退变改变。在进行髋臼周围截骨术时，术前影像学评估应包括股骨头-颈交界处，以防止继发性股骨髋臼撞击，尤其是在晚期骨关节炎患者中。©2015骨科学研究协会。由威利期刊公司出版。《矫形外科学研究》34:1613-1619，2016年。
