全髋关节置换中臼杯放置角度对关节屈伸活动安全性的影响

Angle of acetabular cup in total hip replacement affects the safety of joint flexion and extension

背景:全髋关节置换患者的主要并发症为以脱位为表现形式的不稳定,而脱位等并发症的发生概率与假体特别是臼杯假体的置入角度失误有较大关系。目的:探究全髋关节置换中臼杯置入角度对关节屈伸活动安全性的影响。方法:选取2012年1月到2014年12月在江苏大学附属武进医院接受全髋关节置换治疗的60例患者。利用三维定向监测装置、CT扫描以及图像处理工具,对患者进行臼杯预设角度,设置外展角和前倾角,记录试验数据,并且进行统计学分析。结果与结论:在外展角45°,前倾角15°;外展角60°,前倾角15°;外展角30°,前倾角15°;外展角45°,前倾角5°;外展角45°,前倾角25°,共5种条件下进行不同臼杯角度置入。根据数据统计,在前倾角均为15°的患者中,当臼杯放入时,外展角越大时,骨盆倾斜角度变化导致的患者臼杯外展角变化的范围也越大。患者骨盆前倾角的增加,臼杯前倾角会减小。随着骨盆后倾的角度增加,患者的臼杯前倾角也会变大。此外,在前倾角均为15°的患者中,让臼杯前倾角均保持一致,当患者的臼杯置放外展角增大时,骨盆倾斜角度变化进而导致的臼杯前倾角变化范围就越小。提示臼杯外展角与前倾角两者之间具有相互制约的关系;在臼杯置入时,以较大的前倾角度置入时[安全范围(15±10)°],才能够对患者股骨头更好的包容,降低脱位的概率,使得关节屈伸活动更加安全。

BACKGROUND： Major complication after total hip replacement was instability in the form of dislocation. The probability of above complications has a great relationship with the mistakes of the angle of acetabular cup prosthesis. OBJECTIVE： To explore the influence of angle of acetabular cup in total hip replacement on the safety of joint flexion and extension. METHODS： A total of 60 patients, who underwent total hip replacement in the Wujin Hospital Affiliated to Jiangsu University from January 2012 to December 2014, were enrolled in this study. Three dimensional directional monitoring device, CT scanning and image processing tools were used to preset the angle of the acetabular cup and to set abduction angle and anteversion angle. Test data were recorded and subjected to statistical analysis. RESULTS AND CONCLUSION： Acetabular cup was implanted under five different conditions： abduction angle45°, anteversion angle 15°; abduction angle 60°, anteversion angle 15°; abduction angle 30°, anteversion angle 15°; abduction angle 45°, anteversion angle 5°; abduction angle 45°, anteversion angle 25°. According to statistics,in the patients with anteversion angle of 15°, when the acetabular cup was placed, the bigger the abduction angle, the bigger the range of abduction angle of the acetabular cup induced by pelvic tilt was. If the anteversion angle increased, the anteversion angle of the acetabular cup was reduced. With the increased pelvic tilt angle, the anteversion angle of the acetabular cup was big. Moreover, in patients with anteversion angle of 15°, the anteversion angle of the acetabular cup should keep consistent. When the abduction angle of the acetabular cup increased, the range of anteversion angle of the acetabular cup induced by pelvic tilt was diminished. These data showed that the abduction angle and anteversion angle of the acetabular cup have mutual restriction. When the acetabular cup was placed, big anteversion angle（15±10）° can wrap the femoral head, reduce the incidence of dislocation, and make flexion and extension safe.